1 MEETING 2 OF THE 3 SCIENTIFIC REVIEW PANEL ON TOXIC AIR CONTAMINANTS 4 CALIFORNIA AIR RESOURCES BOARD 5 6 7 8 9 10 SOUTH SAN FRANCISCO CONFERENCE CENTER 11 255 SOUTH AIRPORT BOULEVARD 12 SOUTH SAN FRANCISCO, CALIFORNIA 13 14 15 16 17 18 WEDNESDAY, APRIL 22, 1998 19 9:00 A.M. 20 21 22 23 24 Janet H. Nicol Certified Shorthand Reporter 25 License Number 9764 PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 ii 1 APPEARANCES 2 MEMBERS PRESENT: 3 Dr. John Froines, Chairman Dr. Paul D. Blanc 4 Dr. Craig Byus Dr. Gary Friedman 5 Dr. Anthony Fucaloro Dr. Stanley Glantz 6 Dr. Peter S. Kennedy Dr. Hanspeter Witschi 7 8 REPRESENTING THE CALIFORNIA AIR RESOURCES BOARD: 9 Mr. Manjit Ahuja Mr. Donald Ames, Assistant Chief 10 Mr. Robert Krieger, Associate Air Pollution Specialist Dr. Michael Lipsett 11 Mr. Peter Mathews, Office of the Ombudsman Mr. Kirk Oliver, Staff Counsel 12 Mr. Ralph Propper Ms. Genevieve Shiroma, Chief, AQMB 13 14 REPRESENTING THE OFFICE OF ENVIRONMENTAL HEALTH HAZARD ASSESSMENT: 15 Dr. George Alexeeff, Chief, Air Toxicology & Epidemiology 16 Dr. John Budroe, Staff Toxicologist Dr. Stanley Dawson, Staff Toxicologist 17 Dr. Melanie Marty, Senior Toxicologist 18 19 20 21 22 23 24 25 PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 iii 1 INDEX 2 PAGE AGENDA ITEMS: 3 1 Review of report: Proposed Identification of 1 4 Diesel Exhaust as a Toxic Air Contaminant, February 1998 5 Adjournment 224 6 Certificate of Reporter 225 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 1 1 P R O C E E D I N G S 2 ACTING CHAIRMAN FROINES: I'd like to call the 3 meeting to order. I think we have a long day ahead of us 4 and the sooner we get started, the better. 5 I should say that we have one logistical issue to 6 deal with, and that is that I think it's important for all 7 the panel members to be able to attend the discussion. 8 And as you can see and know, Jim Seiber was not 9 able to be with us because he's in the Netherlands. 10 But we have one further conflict, which is that 11 Paul Blanc has to go up to UC San Francisco to give a talk 12 at noon. 13 So I would propose that we take a lunch break at 14 11:45. Paul can get up to San Francisco, his talk runs 15 until 12:30, and he promises that he'll be back by 1:00 16 under pain of death and burning. 17 So if that's okay with everybody else, we can do 18 that. 19 Bill, is that okay with you? 20 I think that given the logistics of lunch, that 21 might make sense anyway. So 11:45 to 1:00 will be our 22 break. 23 So we'll try and go as far as possible this 24 morning. Although Genevieve and George have said that they 25 have a fairly extended period of description of most recent PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 2 1 events. 2 And so I think that without my taking time to make 3 any other comments, we all are deluged with loads of 4 material, and the one thing I will say is that you do have 5 draft findings which I put together, and I wanted to make 6 everybody on the panel aware that I tried to make those 7 findings very simple. I tried to make those findings by and 8 large reasonably straightforward in the hopes that the panel 9 would then make subsequent modifications. 10 So I wasn't trying to write anything like a final 11 draft at all. I was simply trying to put something together 12 that we would have to work from. So please take that as a 13 draft in process. 14 DR. BLANC: John, is this on? Can people hear me? 15 How about now? 16 Well, John, I'll talk loudly. 17 Could you map out for us what, in broad terms, 18 what the agenda is today? Because appropre of your comment 19 on the draft findings, what I would suggest is that after 20 whatever initial presentation the staff has for us that we 21 actually use your very useful draft as a kind of template or 22 guideline for how we can structure our discussion, because I 23 found that your draft was so useful that I can just see 24 going through it point by point and coming to closure as a 25 group on each of the various subparts of it as a way of PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 3 1 organizing our discussion, if that would be acceptable to 2 the other panel members. 3 ACTING CHAIRMAN FROINES: For those that are 4 confused, since I developed two drafts, you need to know 5 what he's talking about. He's talking about the draft where 6 I went through some of the definitional issues. 7 DR. BLANC: No. I actually mean the draft of your 8 findings. 9 DR. FUCALORO: He's talking about the 22 points. 10 DR. BLANC: I would just go through the 22 points. 11 I think we can refer to the other memo as needed when we 12 come to questions of definitions and what our charge is, but 13 I just found your draft findings so useful that it would 14 probably be a good way to structure our focus discussion. 15 ACTING CHAIRMAN FROINES: Well, I think that 16 that's an interesting suggestion. 17 Normally what's happened in the past is that after 18 the presentation is made by staff of our ARB and OEHHA and 19 during that time there are always questions that can be 20 raised of the staff during their presentations, but then in 21 a sense it reverts to the panel itself. 22 Normally what we have done is say under Part A 23 Tony will be the lead replacing Jim Seiber for this meeting 24 and what Tony would then do is make any comments that he 25 chooses to make and then he would then ask for comments from PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 4 1 panel members around the room. 2 If you're suggesting that rather than go around 3 the room, we go through the document on Part A during that 4 time, that's another way of doing it. So we should decide 5 that pretty quickly. 6 DR. BLANC: Well, that's why I bring it up right 7 at the start, because I think it would sort of guarantee 8 that at the end of the day we had given a balanced amount of 9 time and had a draft, a modified draft document, that would 10 be our product at the end of the day. 11 But I guess I would ask Tony if you would feel 12 comfortable with the first half if, let's say, the first ten 13 points for example address some of the key areas of the 14 salient features of that part of the document and then you 15 actually reviewed the -- or coordinated the discussion on 16 the health, so I would assume that the points 11 through 22 17 or the 11 through 19 or so of your draft document would, you 18 know, since you formulated it that way. 19 ACTING CHAIRMAN FROINES: If we did that, what 20 that then means is that we go through and say Stan has a 21 point that's not in the document that he can raise that at 22 an appropriate time. 23 DR. BLANC: Yeah. 24 DR. FUCALORO: Since you have more experience in 25 these sort of things I'll do whatever you wish. I can PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 5 1 handle it either way. 2 ACTING CHAIRMAN FROINES: What do others feel? 3 DR. GLANTZ: I actually think that's a good idea 4 because often the findings get kind of rushed at the end of 5 the meeting, and this way we would focus on the findings. 6 And, I mean, I think, though, there are -- I do 7 have a few comments on the actual document, the report, that 8 I think we would want to have. 9 I think what we maybe ought to do is follow Paul's 10 suggestion. Probably in the context of that discussion 11 there will be some changes to the report brought up, but 12 then after we've done that, to just go through the report 13 with anything anybody hasn't talked about to make sure that 14 because we are approving the report too, and as well as 15 issuing the findings, so we want to make sure everybody is 16 happy with the report. 17 I think it's a good idea, actually. 18 ACTING CHAIRMAN FROINES: Peter -- probably 19 shouldn't have put Peter and Hanspeter next to each other, 20 because every time we turn that way, one or the other is 21 going to answer. 22 Well, that seems, unless there's dramatic 23 disagreement, it seems to me we're going to go that way. I 24 think it will work fine. It will help, if -- this is such 25 an immense document what we need to do is to try to organize PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 6 1 how we approach it so we can systematically get through in a 2 reasonable period of time with significant depth to the 3 discussion. I think that's important that we have the level 4 of depth that's required for making the determination. 5 So having worked on these internal matters, 6 Genevieve, if you could introduce yourself and others. 7 And so that -- everybody does have the staff -- 8 the two documents that I prepared, right? 9 DR. GLANTZ: One document? 10 ACTING CHAIRMAN FROINES: One was the definitional 11 one and one was the findings. 12 DR. GLANTZ: Is the definitional one this e-mail? 13 ACTING CHAIRMAN FROINES: Yes. 14 And we will also be making available to you this 15 morning two other documents that I received this morning. 16 They are both from the National Institute for Occupational 17 Safety and Health, and they both represent new risk 18 assessments that have been conducted by NIOSH and are going 19 to be published in the July issue of the American Journal of 20 Industrial Medicine. So we'll have that as another risk 21 assessment approach, and I'll get Peter to work on that. 22 I don't think there's any other -- everybody has 23 the Allan Smith document, because that was in the comments, 24 I believe. And that's a very nice document and I hope we 25 have it as some discussion point, because anything that PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 7 1 helps simplify any of these discussions I think is to our 2 advantage. 3 So anyway, Genevieve. 4 MS. SHIROMA: Thank you. Good morning, 5 Dr. Froines and members of the panel. My name is Genevieve 6 Shiroma. I am chief of the Air Quality Measures Branch at 7 the Air Resources Board. 8 My branch is responsible for implementing the 9 toxic air contaminants identification program, specifically 10 the exposure portion. 11 With me is Robert Krieger of my staff, who is lead 12 on the exposure assessment for diesel exhaust. 13 In accordance with AB 1807, toxic air contaminate 14 statutes, we are here today to seek, along with the staff of 15 the Office of Environmental Health Hazard Assessment, to 16 seek your approval of the February 1998 draft report 17 proposed identification of diesel exhaust as a toxic air 18 contaminant. 19 We will present an overview of the report, 20 summarize the public comments received and we will also be 21 proposing a number of revisions to the report for your 22 assessment. 23 Now, this is an outline of today's presentation. 24 I'll start out with a short introduction, and then we'll 25 move on to an overview of the report. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 8 1 Robert will give a short overview of the Part A 2 exposure assessment. 3 Dr. George Alexeeff, with the OEHHA, will present 4 the overview of the Part B health risk assessment. 5 Now, following that, Robert will then summarize 6 the comments that we received on Part A and our proposed 7 revisions. 8 Then Dr. Melanie Marty with OEHHA will summarize 9 the Part B comments and present proposed revisions. 10 Now, as you know, we have a comprehensive -- we 11 have a comprehensive air toxics program in California. The 12 toxic air contaminant program was established by AB 1807 in 13 1983. The program is a two-phased program. 14 ACTING CHAIRMAN FROINES: Can I interrupt you 15 before we start? 16 MS. SHIROMA: Yes, you may. 17 ACTING CHAIRMAN FROINES: Because when you went 18 through all that, a little signal went off in my ear. And 19 this reflects to George and Melanie. 20 The panel has had the benefit of reading the 21 responses to the comments and so hopefully you can keep, you 22 can address the most important comments in a reasonably 23 efficient fashion, because I think that the panel needs to 24 have a lot of time to discuss these things and so -- and the 25 panel is very active and so the -- we should try and keep PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 9 1 the time for -- to go over things that people have already 2 hopefully read to some minimum and if there's ever any 3 question, the panel can reraise issues, the panel is not 4 precluded, but I think we also need to make sure we move 5 along at a reasonable pace. 6 MS. SHIROMA: That's fine. We'll keep it succinct 7 and brief. 8 Again, just for an overview on the program, I have 9 the definition of a toxic air contaminant up on the screen. 10 The program is a two-phased program. 11 A toxic air contaminant is defined in the law as 12 an air pollutant which may cause or contribute to an 13 increase in mortality or in serious illness or which may 14 pose a present or potential hazard to human health. 15 The first phase of the program is the risk 16 assessment or the identification phase. 17 The second phase is the risk management phase 18 where the need for an appropriate degree of control of a 19 toxic air contaminant is assessed. 20 As you know, we are in the first phase, the 21 identification of diesel exhaust as a toxic air contaminant. 22 Now, for the benefit particularly of the new SRP, 23 the newer SRP members, we thought at this point we'd have 24 Kirk Oliver with our office of legal affairs, just briefly 25 describe each of our responsibilities under the statute. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 10 1 Now, Kirk has been delayed in traffic, and so I 2 will just briefly go over the items that he wanted to 3 outline for you and then he will be here eventually. If you 4 have questions, he'll be here to answer questions. 5 ACTING CHAIRMAN FROINES: I just want to make one 6 comment, that that definition I made available to the panel. 7 I left one piece out. I just want to read it so that 8 everybody has it in the back of their mind. 9 And that is it's section E under 39650. It says 10 that while absolute and undisputed scientific evidence may 11 not be available to determine the exact nature and extent of 12 risk from toxic air contaminants, it is necessary to take 13 action to protect public health. 14 I think that needs to be seen within the context 15 of the definition as well. 16 DR. GLANTZ: Genevieve, if Kirk will ultimately 17 get here, why don't you get on with the science and he can 18 talk about the law when he gets here. 19 MS. SHIROMA: That would be fine. 20 One of the things that he wanted to make real 21 clear is that the ARB indeed is responsible for the exposure 22 part of the science, the OEHHA on the health part of the 23 science, and that OEHHA by the statute is required to 24 provide a range of risk. 25 And also to indicate whether or not there is a PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 11 1 threshold below which no adverse health effects are 2 expected. 3 And then you, the SRP, are responsible for 4 reviewing the report for sound science. 5 John, is that satisfactory with you? 6 ACTING CHAIRMAN FROINES: All right. 7 MS. SHIROMA: Okay. Then the next slide is just a 8 list of the criteria we use for prioritization. It really 9 is the first step of looking at entering a compound into the 10 program. We look at things like potential risk to public 11 health, the exposure, usage in California, persistence. 12 DR. FUCALORO: Excuse me. Just for clarification, 13 this prioritization is for those substances that you 14 currently have in the pipeline to consider, so this is 15 the -- 16 MS. SHIROMA: That's right. In previous meetings 17 we've presented a list of several hundred substances that we 18 continually prioritize. 19 The next one shows a flow chart of the process. 20 Once we have selected a compound, we begin the process of 21 producing the report. Very key part is that they're 22 distributed for public review and comment with public 23 workshops where interested parties can discuss the issues 24 with both the staff and the Scientific Review Panel members. 25 After that we then go through looking at the PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 12 1 comments and revising the report accordingly. 2 We then submit it to you as we have. 3 Here is Kirk. 4 And go through a process of seeking your approval. 5 If you approve the report and you develop 6 findings, which are then submitted to the Board, we then put 7 out a hearing notice for a 45-day comment period, and then a 8 Board hearing to take formal action to identify the 9 substance. 10 Our Board simply determines in a regulatory format 11 is this substance a toxic air contaminant and adds that then 12 to the regulation. 13 Then at that point, the second phase, the 14 right-hand side of the flow chart begins where the risk 15 management phase begins where the degree of control is 16 reassessed. 17 Now, the next slide shows the types of criteria we 18 took into consideration when we entered diesel exhaust back 19 in 1989, in that the potential for non-cancer and cancer 20 health effects, widespread exposure in California, the 21 International Agency for Research on Cancer designation as a 22 probable human carcinogen, US EPA had begun its evaluation 23 of diesel exhaust health effects and overall method of 24 criteria for the definition of a toxic air contaminant at 25 that time. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 13 1 Now, this next slide is a chronology just showing 2 that again since 1989 there has been an extensive effort to 3 go through a thorough public and scientific process. 4 Couple of items to note. 5 In January of 1996 the OEHHA, the ARB, the Health 6 Effects Institute, National Institute of Occupational Safety 7 and Health, World Health Organization and US EPA sponsored a 8 human health study workshop. 9 October of '97 the ARB and OEHHA staff provided 10 you, the panel, with an overview of the report and the types 11 of comments we were receiving on the May draft. 12 And then on February 23rd we released this report. 13 In March you held a meeting with invited 14 scientists. 15 Overall the draft report has been through three 16 comment periods, three public workshops, and the staff have 17 participated in numerous individual meetings with interested 18 stakeholders. 19 Now, at this point we can move on to the overview 20 of the report. 21 And, again, Kirk Oliver is here for questions. 22 I'm going to now turn the presentation over to 23 Robert Krieger. After Robert we'll hear from Dr. Alexeeff. 24 Robert is going to give you, again, a short 25 overview of the exposure assessment portion of the report. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 14 1 DR. GLANTZ: Since Kirk just showed up, do you 2 think it would be worth him just briefly saying what he was 3 going to say? 4 MS. SHIROMA: Yes, I do, actually think it would 5 be worth it. 6 ACTING CHAIRMAN FROINES: No more than five 7 minutes. 8 DR. GLANTZ: Yeah, briefly. 9 MR. OLIVER: Thank you, Dr. Glantz and Dr. Froines 10 and members of the panel. And I apologize for being late. 11 The traffic in this area, as you know, is very heavy, and 12 was so today. 13 And I promise I can get through this in less than 14 five minutes, so let's get going on it. 15 The AB 1807 identification statute is quite clear 16 on the responsibilities of the ARB, OEHHA and the Scientific 17 Review Panel. 18 Primarily the ARB is to prepare a report in a form 19 which may serve as the basis for regulatory action regarding 20 the formal identification of the substance. 21 In doing this, the ARB staff is required to 22 consider research and monitoring data, emissions inventory 23 data, information on estimated actual exposures to 24 substances based on geographic and demographic data, and on 25 data derived from analytical methods that measure the PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 15 1 dispersion and concentrations of substances in ambient air 2 and in indoor environments, as well as ambient conditions. 3 The OEHHA staff, at the request of ARB, is 4 required to evaluate the health effects of and prepare 5 recommendations regarding a substance, considering all 6 available scientific data, including but not limited to 7 relevant data provided by the ARB, the State Department of 8 Health Services, the Occupational and Safety and Health 9 Division of the Department of Industrial Relations, the 10 Department of Pesticide Regulation, international and 11 federal health agencies, private industry, academic 12 researchers and public health and environmental 13 organizations. 14 The OEHHA evaluation must assess the availability 15 and quality of data on health effects, including potency, 16 mode of action and other relevant biological factors of the 17 substance. 18 The OEHHA evaluation is also required to contain 19 an estimate of the levels of exposure which may cause or 20 contribute to adverse health effects. 21 Where it can be established that a threshold of 22 adverse health effects exists, the estimate shall include 23 both of the following factors. One, the exposure level 24 below which no adverse health effects are anticipated; and, 25 two, an ample margin of safety which accounts for the PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 16 1 variable effects that heterogeneous human populations 2 exposed to the substance under evaluation may experience, 3 the uncertainties associated with the applicability of the 4 data to human beings and the completeness and quality of the 5 information available on potential human health exposure to 6 the substance. 7 However, in cases where there is no threshold of 8 significant health effects, the OEHHA is required to 9 determine the range of risk to humans resulting from current 10 or anticipated exposures to the substance. 11 The report compiled by the ARB and contributed to 12 by OEHHA shall be made available to the public and must be 13 formally reviewed by you, the Scientific Review Panel. 14 You're required to review the scientific 15 procedures and methods used to support the data in the 16 report, the data itself and the conclusions and assessments 17 on which the report is based. 18 Your panel is required to submit its written 19 findings to the ARB on this report within a specified time 20 frame. 21 If you, the panel, determine that the health 22 effects report is not based upon sound scientific knowledge, 23 methods or practices, the report shall be returned to the 24 ARB, and the ARB with OEHHA is required to prepare revisions 25 to the report, which have to be resubmitted to you for PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 17 1 re-review. 2 Within ten days of the receipt by the ARB of your 3 findings that the report does meet the legal requirements, 4 the ARB staff is required to prepare a hearing notice and 5 propose regulations for the proposed identification of the 6 substance under review by you. 7 That ends my summary of your various 8 responsibilities. 9 Are there any questions you have now? 10 MR. KRIEGER: Thank you, Kirk. 11 Thank you, Genevieve. 12 Good morning, Dr. Froines and members of the 13 panel. 14 Right now I'd like to give you a brief 15 presentation on the Part A exposure assessment. 16 Our Part A was also contributed, I'd like to also 17 note, that Part A was contributed by the other divisions 18 within the Air Resources Board, Monitoring and Laboratory 19 Division, the Technical Support Division, the Research 20 Division, Mobile Source Division, and our Stationary Source 21 Division. 22 I'll begin my overview of Part A with the 23 properties of diesel exhaust. 24 As you know, diesel exhaust is a complex mixture 25 of thousands of gases and fine particles emitted by internal PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 18 1 combustion engines. 2 Some of the components are known human 3 carcinogens, like arsenic and benzene. 4 It also includes over 40 substances that have been 5 identified as toxic air contaminants and by the US EPA as 6 hazardous air pollutants. Over 90 percent of these 7 particles are less than one micron in diameter. 8 This overhead shows the 40 compounds that are 9 federal hazardous air pollutants and have been identified by 10 the Air Resources Board as toxic air contaminants. 17 of 11 these also have IARC, or International Agency for Research 12 on Cancer, designations. 13 This slide shows the sources of emissions of 14 diesel exhaust in California. The majority of these 15 emissions, as you can see, come from on-road motor vehicles. 16 To characterize exposure to diesel exhaust, we use 17 particulate matter concentrations. To estimate 18 population-weighted average outdoor concentrations of diesel 19 exhaust, PM 10, we use receptor modeling techniques which 20 include chemical mass balance results from several studies, 21 ambient PM 10 monitoring network data, and the 1990 22 emissions inventory. 23 From the results of this analysis, we estimated 24 that Californians in 1990 were exposed to a 25 population-weighted average outdoor concentration of three PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 19 1 micrograms per cubic meter. 2 We have also estimated in 1995 and future year 3 outdoor average concentrations. 4 These future concentrations, important to note, 5 take into account the measures and control measures by ARB 6 that have been adopted to date. 7 In December of 1993 we conducted a study to 8 determine near-source concentrations near a Long Beach 9 freeway. The results indicate that near-source 10 concentrations may be up to three times that of outdoor 11 ambient air concentrations. 12 This slide gives you an indication of what other 13 researchers have done to measure outdoor atmospheric 14 concentrations of diesel exhaust PM. 15 The comparison shows well with those of other 16 researchers. 17 We estimated the outdoor population-weighted 18 concentration in a model to calculate indoor and total air 19 exposures. This model, the California population indoor 20 exposure model, accounts for the amount of time spent 21 indoors and outdoors. 22 The model was developed under contract to ARB to 23 improve estimates of population exposures to toxic air 24 contaminants. The model uses relevant data, such as 25 distributions of California building air exchange rates, PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 20 1 activity patterns data, and air concentrations of diesel 2 exhaust particles as inputs to develop indoor and population 3 exposure estimates across all environments. 4 The estimated average indoor exposure is in 1990 5 to be two micrograms per cubic meter and the average total 6 air exposure, including outdoor and indoor, to be 2.1 7 micrograms per cubic meter. 8 We have also done the comparable analysis for the 9 indoor and total exposure analysis for 1995 and 2010 as 10 shown in the overhead. 11 Now I want to address some of the findings of the 12 CE-CERT study, or the College of Engineering Center for 13 Environmental Research and Technology at the University of 14 California at Riverside. 15 I will provide some background on the purpose of 16 the study and then a brief summary of the results. 17 To address the effects of diesel fuel composition, 18 we have on the toxic exhaust -- 19 ACTING CHAIRMAN FROINES: Excuse me. Is the 20 average population-weighted average for Southern California 21 3.6 micrograms per cubic meter? 22 MR. KRIEGER: Yes, that's the outdoor average. 23 ACTING CHAIRMAN FROINES: What's the range? 24 MR. KRIEGER: The range of exposures for outdoor 25 concentrations goes from .2 to 3.6. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 21 1 ACTING CHAIRMAN FROINES: That can't be an average 2 then. 3 MR. KRIEGER: That's not an average. 4 ACTING CHAIRMAN FROINES: What's the range? 5 What's the distribution look like? 6 MR. KRIEGER: Within the South Coast? 7 ACTING CHAIRMAN FROINES: Yes. 8 MS. SHIROMA: We'll look that up. 9 MR. KRIEGER: We'll look that up for you. 10 ACTING CHAIRMAN FROINES: I'm particularly curious 11 because of your RCL, because if you're up to 3.6 and heading 12 towards five, you're starting to get to another number. 13 MR. KRIEGER: In order to make the best use of the 14 study designed for the CE-CERT study, a technical advisor 15 committee was formed, which included members from the Engine 16 Manufacturers' Association, oil refiners, ARB and OEHHA 17 staffs. 18 The study design designated the testing of one 19 heavy duty diesel engine that represents the majority of the 20 market share in California. They tested this on three 21 fuels, the pre-1993 regulation fuel, low aromatic and an 22 alternative formulation fuel. 23 The engine was tested using the US EPA's 24 heavy-duty diesel transient federal test procedures. 25 Multiple samples collected during multi-day testing for each PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 22 1 of three fuels was done. 2 To maximize the resources available and to address 3 the overall goal and purpose of the study, CE-CERT met 4 several objectives. They quantified a number of items, 5 including the criteria pollutants as you can see; size 6 fraction characteristics of the PM 2.5 and PM 10; carbonyl 7 analysis; elemental and organic carbon analysis; particle 8 and gas phase PAH and nitro-PAH, nitrosomorpholine analysis. 9 They also determined the mutagenicity and an attempt to 10 quantify the dioxins for methods development. 11 Testing was conducted from December 1996 to 12 January 1997. 13 The final draft report was approved by the ARB's 14 research screening committee on April 3rd, 1998. 15 The results showed that the emission reductions in 16 both PM and NOx, oxides and nitrogen, from the use of new 17 reformulated fuel meets ARB's predictions set forth in the 18 1988 diesel fuel regulation. 19 While the mass has been reduced, the chemical 20 composition of the exhaust, per milligram per brake 21 horsepower per hour, from the old and new diesel fuels are 22 similar. 23 DR. FUCALORO: Excuse me. I read the CERT report 24 and that doesn't seem to be the case. I would just look at 25 some of the graphs, and they seem to be quite different in PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 23 1 certain compositions. 2 I can give you a page 67, for example. If you 3 look at that, the weighted total between the pre '93, the 4 low aromatic and the reformulated and -- 5 DR. GLANTZ: What page? 6 DR. FUCALORO: Page 67. That's one. There's 7 several others. But it seems to be some significant 8 difference in some of the components, many of which are 9 known to be toxins. 10 MR. AMES: Dr. Fucaloro, this is Don Ames, with 11 the ARB staff. 12 Let me first take a shot at this. 13 And that is what we were attempting to do is look 14 at the toxic air contaminants that Robert mentioned earlier. 15 There are 40 known toxic air contaminants in diesel exhaust 16 and one of the issues raised to us years ago by some 17 industry representatives was the question if you would find 18 these same toxic air contaminants in the old fuel exhaust 19 and the new fuel exhaust or would many of them disappear? 20 So part of the objective of this study was to look 21 at that fingerprint and see if the relative proportion when 22 you account for the reduced mass from the exhaust of the new 23 fuel, would you have the same relative proportion of those 24 40 toxic air contaminants. 25 And a general answer is, yes, although there are PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 24 1 some exceptions, but, yes, we largely found those toxic air 2 contaminants to be present with the new fuel exhaust as well 3 as the old fuel exhaust, and so that's the general answer. 4 But when you look at individual species you may 5 find some slight differences, and we have some staff from 6 our research division if you want to get into more details. 7 ACTING CHAIRMAN FROINES: I had a question about 8 that, because when I looked at the data, there are some 9 chemicals that I look at closely because I think they're so 10 particularly dangerous, and one of them is 1,3-butadiene, 11 which I think is the most toxic of everything, and it seems 12 to me when I looked at it, it seems as though the 13 1,3-butadiene went up rather than going down, and that's an 14 important issue. 15 DR. FUCALORO: It goes up from 1.8 to 2.46 16 milligrams per braking -- for, I don't know, BHP, what does 17 the B stand for? 18 MR. KRIEGER: Brake horsepower. 19 DR. FUCALORO: It's units of energy, right? Power 20 times time, right? So per joule. It goes up in that case. 21 Same with benzene as a matter of fact, even the 22 low aromatic, which I don't know if that's correct, but the 23 low aromatic fuel has a higher benzene emission than the 24 higher aromatic fuel. Unless I'm reading this wrong. 25 MS. SHIROMA: I'd like to introduce Manjit Ahuja PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 25 1 and Ralph Propper from our Research Division, who were the 2 contract monitors for the CE-CERT report. 3 MR. AHUJA: Yes. As your question is quite valid, 4 the fuel, the low aromatic fuel is a combined fuel and it is 5 not a commercial fuel. It is used for research purposes. 6 And, yes, we did find that the benzene went up and 7 1,3-butadiene did go up in fact quite significantly. 8 But if you were to go and take a basket of 9 fuel-outs from commercial outlets, it may be different than 10 what we have found here. 11 MR. AMES: One thing we'd like to point out is 12 that when you do a toxic air contaminant weighted factor and 13 you multiply potency times mass for each of those toxic air 14 contaminants, we do see a benefit to the new fuel, a 15 reduction in potential cancer risk from the exhaust relative 16 to the brake horsepower and that's one important point for 17 the average fuel that's out there. 18 DR. FUCALORO: Well, I was going to say, just look 19 at page 74, Table 30, and in terms of a fingerprint just 20 looking at the numbers, I think you can see that there is 21 quite a difference in the composition of the organics that 22 are listed in this table from the three fuels, the pre '93, 23 I understand the low aromatic is not a fuel that's available 24 to the public, and the reformulated blend, you can see 25 rather significant differences. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 26 1 And that's why I'm just wondering about the 2 statement that the diesel chemical composition, and I guess 3 you mean diesel exhaust chemical composition fingerprint is 4 same in the old and the new. I was not clear what you mean 5 by the new. Do you mean the low aromatic or the 6 reformulated? 7 But in either case, I think that one could see 8 that there's a difference and that can be somewhat 9 misleading, that statement, in my view. Now, maybe I'm 10 wrong and you can correct me if I am. 11 ACTING CHAIRMAN FROINES: I think that the other 12 question that I have is on this list, some of the compounds 13 go up and some go down. And what's missing here on this 14 particular list are the nitro-PAHs, which I take as being 15 some of the most important. 16 And also it doesn't -- isn't able to address the 17 degree of nitrousation that could occur under conditions of 18 atmospheric chemistry. 19 So I think we want to move on past the CERT thing 20 so we may need to go back and not focus so much on detail. 21 I think we're going to need to have some sort of the 22 conclusory sense of what the implications are. 23 Clearly, I would conclude one thing and that is 24 that a great deal of more research is needed to look at the 25 composition of diesel fuels and their combustion products PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 27 1 over the next few years, and I think that that's something 2 we probably would all agree on. 3 But I think what Tony and I are sort of getting at 4 is the take-home lesson isn't entirely clear here. 5 DR. GLANTZ: I just wanted to clarify something. 6 My understanding, and I mean I'm not the chemist 7 here, but my understanding is what you were saying and what 8 the CERT study was saying is that the new fuels produce less 9 total emissions, but that the distribution of different 10 compounds within, per unit mass of emission was similar. I 11 mean, is that -- is that what you meant? 12 MR. AMES: That's correct. Because we wanted -- 13 DR. FUCALORO: I understood it that way. My 14 statement is predicated on that understanding that the -- 15 because this is per unit energy and the fact that 16 distribution is dissimilar in some ways and of course it's 17 how dissimilar is becomes perhaps their definition of what 18 similar is different than mine. 19 I would think for example for 20 2,3,5-trimethylnaphthalene the pre '93 diesel fuel had 283 21 micrograms per unit energy that they do, and the low 22 aromatic had 15. So 15 to 283 seems to be quite a different 23 ratio, but maybe I'm reading it wrong and that's all. 24 I certainly don't want to hold us up. 25 ACTING CHAIRMAN FROINES: I have one question that PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 28 1 has to do with bioavailability. What's the relative 2 particle size, aerodynamic diameters of these different 3 fuels? Because clearly if the particles get smaller, then 4 you have more bioavailability potentially and so you can 5 have a greater risk rather than a lesser risk. 6 MR. PROPPER: We didn't find any significant 7 difference in the particle size in these fuels. 8 However, when we planed the study it was before 9 the great concern about the ultrafine particles arose. So 10 that we only looked at larger size cuts like one micron, 2.5 11 micron. 12 I would like to add in response to Dr. Fucaloro, 13 you're quite right, the major difference that we did see in 14 the target analytes between the new and the old fuel was in 15 the volatile PAHs, and this is consistent with the fact that 16 the newer fuels contain much less volatile PAHs in the fuel. 17 And for the three fuels you find quite consistent 18 correlation between the amount of PAH in the fuel and the 19 amount of volatile PAH submitted. 20 I'd like to add, though, that the main toxic 21 concern has been with the more particle phase PAHs like 22 benzo(a)pyrene, although it still is good to see those 23 numbers go down in the volatile PAHs. 24 MR. KRIEGER: One more to add about the size of 25 the particle too, and the study showed that 98 percent of PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 29 1 the particle is less than 2.5 microns. The majority is 2 confirmed with what we said in our report. 3 Back on the question on the exposure of the South 4 Coast Air Basin, the upper end is 4.5 micrograms per cubic 5 meter. 6 ACTING CHAIRMAN FROINES: I shouldn't ask this 7 question. 8 When you have the 4.5 days, do you also have a lot 9 of nitrogen oxides in the air on those days? 10 Let it go. It's not about -- 11 DR. GLANTZ: Genevieve, the chair has withdrawn 12 the question. 13 MS. SHIROMA: We'll go on with the presentation. 14 ACTING CHAIRMAN FROINES: Don't worry about it. 15 You know what I'm worried about. The higher the 16 PAH stage, the higher the nitro-PAH days. 17 Let's go. 18 MR. KRIEGER: Bullet No. 4, the mutagenicity we 19 found is lower in the new fuel. The results indicate that 20 the most mutagenic fraction for the PM is an unidentified 21 fraction from the fractions containing PAH and nitro-PAH. 22 However, the differences are not statistically significant 23 since the study was not robust enough. They tested one 24 engine on three fuels. 25 DR. FUCALORO: It's 55 percent, mutagenicity is PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 30 1 now 55 percent. And it may not be significant, I certainly 2 didn't do the statistics, but it is significantly lower, am 3 I correct? I mean, I meant significantly not in a 4 mathematical -- it is appreciably lower? 5 MR. KRIEGER: Yes. 6 MS. SHIROMA: For the data set for the study, and 7 the data set of itself, but looking at making some sort of 8 broad brush conclusion, okay, that's what Robert is 9 referring to. 10 MR. KRIEGER: I think you're correct. Not on a 11 mathematical sense, statistically, but from appearance, yes, 12 yes, it is. 13 ACTING CHAIRMAN FROINES: I have done tens of 14 thousands of Ames tests over the years, and so I know this 15 one pretty well. And I think saying that it's lower is 16 fine, but I think one has to be careful and we'd have to 17 look -- were they doing direct mutagenicity or oro chloro 18 induced S9 fractions? 19 DR. FUCALORO: Both. The S9, plus they did it 20 both, with and without. Am I correct? 21 MR. PROPPER: Yes. They did both kinds, and there 22 are somewhat different result, but not drastically different 23 results between whether they did the plus S9, plus S9. They 24 also used vapor phase and particle phase. 25 I'd like to point out that the bulk of the PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 31 1 mutagenicity was in fractions more polar than contained in 2 the nitro or PAHs. We don't know what's in those. 3 ACTING CHAIRMAN FROINES: The bulk of the 4 mutagenicity was, say that again? 5 MR. PROPPER: Was in fractions more polar than 6 those that contain the nitro-PAHs and also obviously the 7 PAHs. 8 DR. FUCALORO: The seventh fraction? 9 MR. PROPPER: Yes, that's correct. 10 ACTING CHAIRMAN FROINES: Well, I think it's 11 important to say that the mutagenicity was low, but 12 mutagenicity goes down by a factor of two is almost 13 inconsequential and for the most part, so I think what it 14 suggests is that we need to do more work to carry it 15 further. 16 I think it's good findings and important findings, 17 but I think it does suggest the need for further follow-up. 18 MR. KRIEGER: Fifth bullet on dioxins. 19 The study detected dioxins in both old and new 20 fuels, but could not be quantified. 21 However, the method development for collecting 22 these dioxins was improved and it goes back to the statement 23 Dr. Froines made, overall the study points to a need for 24 additional research on more engines and under various 25 operating conditions and fuels. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 32 1 In summary, diesel exhaust is a complex mixture of 2 gases, vapors and fine particles, with the majority as fine 3 particulate matter. 4 As the CE-CERT study indicates, it remains a 5 complex mixture after reformulation with the same toxic 6 substances. 7 Most of the emissions of diesel exhaust, PM 10, 8 are from on-road motor vehicles. 9 ACTING CHAIRMAN FROINES: It also is important to 10 realize what the atmospheric conditions you're operating in, 11 because within that particular context we're concerned with 12 different health effects. There's a clear evidence for 13 acute health effects, respiratory effects associated with 14 diesel exhaust and so that part of the question is is the 15 relationship between the technology, the fuel and the 16 emissions and the health effects that you're interested in 17 learning about. 18 And I think we want to be careful to not always 19 have everything be part of some sort of tyranny of cancer, 20 so that we're not only looking at one kind of end point as 21 we evaluate this data, and that's what tends to happen. 22 MR. KRIEGER: In summary and to conclude, the 23 population-weighted average outdoor diesel exhaust 24 concentrations decreased from three micrograms per cubic 25 meter in 1990 to 1.7 microgram per cubic meter in 2010. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 33 1 Near-freeway concentrations of diesel exhaust PM 2 10 were found to be up to three times that of ambient 3 concentrations. 4 MS. SHIROMA: Sorry to interrupt, Robert. 5 Dr. Froines, just to note that when you were 6 asking about the range of concentrations that didn't account 7 for this near-source scenario where near the, in this 8 particular case it was the Long Beach freeway, the 9 concentrations were found to be up to three times higher 10 than the ambient. 11 MR. KRIEGER: Finally, we have considered a 12 person's daily activity and exposures to different 13 environments to estimate for 1990 an average total air 14 concentration of 2.1 micrograms per cubic meter. 15 We have done an additional analysis to estimate 16 for 1995 the average total air concentration of 1.5 17 micrograms per cubic meter. 18 At this point -- 19 DR. FRIEDMAN: I'm a little confused about the 20 first item, which says that the concentration will be down 21 to 1.7 in 2010, and that's already lower than that in '95. 22 I'm not clear how those two fit together. 23 MR. KRIEGER: The 1995 estimate is a total air 24 exposure estimate. That includes weighted concentration 25 from indoor and outdoor exposures. So the estimate of 1.5 PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 34 1 includes within that outdoor concentrations the exposure to 2 indoor air as well. It's not a 24-hour outdoor exposure. 3 It's an integrated time-weighted exposure. 4 MS. SHIROMA: The number -- 5 DR. BLANC: The number you're referring to is for 6 a target for outdoor, which is higher than indoor, and this 7 number includes -- is something between the mean for outdoor 8 and the mean for indoor, because it's an average 24-hour 9 exposure. 10 DR. FRIEDMAN: I see. 11 How did you arrive at the 1.7 for 2010? Did you 12 sort of do an extrapolation of the current trends? 13 MR. KRIEGER: Extrapolation of the current trends. 14 That takes into account all the controlled measures and 15 future control measures that have been adopted to date in 16 our emissions inventory. 17 ACTING CHAIRMAN FROINES: Everybody is so 18 comfortable in this room. We're going along at this kind of 19 rolling pace. I think we ought to create a little more 20 tension and move on in a more less rolling pace. 21 I want to ask, it seems to me if in fact you get 22 threefold increases in measurements near freeways, or at 23 least in the few freeways you've looked at, does that 24 represent something we should look more into? 25 I mean, are people who live near freeways having PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 35 1 quite significant exposures to diesel in California? We 2 live in a state of freeways, after all. 3 MS. SHIROMA: Should you approve the report, 4 should the Board identify diesel exhaust as a toxic air 5 contaminant, then during the risk management phase, we at 6 the ARB will be looking further into refining that estimate 7 and then also looking at whether something else can be done. 8 MR. KRIEGER: At this point I'd like to turn the 9 presentation over to Dr. George Alexeeff, of the Office of 10 Environmental Health Hazard Assessment, to give an overview 11 of the Part B report. 12 ACTING CHAIRMAN FROINES: Welcome, George. 13 DR. ALEXEEFF: My name is George Alexeeff. I'm 14 deputy director for Scientific Affairs of the Office of 15 Environmental Health Hazard Assessment in the California 16 EPA. 17 ACTING CHAIRMAN FROINES: Have we congratulated 18 you on this promotion? 19 DR. ALEXEEFF: Well -- 20 DR. FUCALORO: You received my card, haven't you? 21 DR. ALEXEEFF: Yes, thank you. 22 DR. GLANTZ: I guess the question is when you say 23 can we congratulate him, does that mean is it proper or is 24 he glad he was promoted? 25 DR. ALEXEEFF: Somehow I'm still on this hot seat, PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 36 1 so I don't know what has changed. 2 MS. SHIROMA: It's gotten hotter. 3 DR. ALEXEEFF: In any case, I'll be presenting a 4 review summary of the key issues in the health risk 5 assessment report for diesel exhaust called Part B. 6 And the last time I made a presentation before the 7 panel was on October 16th, and on that day we came to the 8 panel with five major issues that were being raised in the 9 comments, and we seeked your advice on how to address some 10 of those issues and we have -- 11 DR. BLANC: Sought. 12 DR. ALEXEEFF: Sought, thank you. 13 So we have implemented your comments or 14 suggestions in this version here. And I'll touch upon those 15 as I go through the presentation. 16 Also as you see here these are the major topics I 17 will be discussing. Some of these topics are more 18 contentious than others. The ones of greatest interest, 19 both in terms of the commentators, and I think in terms of 20 the discussions we had last month, are the human 21 occupational studies and the cancer quantitative risk 22 assessment. So I'll go in greater depth for those, but I 23 felt it's important to sort of give a complete picture. 24 Also, as you know, this document is very 25 technical. There's a lot of information in here, and I have PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 37 1 the relevant experts on each of those topics here present, 2 so as issues come up we can have them come up and answer 3 those questions. 4 Okay. First, in terms of the human acute -- 5 actually, I'm going to make one more comment before I start 6 on this. 7 Now, we have reviewed the scientific literature 8 and all the comments up until, essentially just about this 9 point. As mentioned, Dr. Froines even presented us with 10 some information from the Federal Register this month. In 11 February of '98, couple months ago, US EPA came out with 12 their health assessment of diesel exhaust, so this document 13 we have here is very current. 14 First is the human acute non-cancer health 15 effects. There are increased symptoms of eye, throat and 16 bronchial irritation. There's increased physiological 17 symptoms such as headache, nausea and vomiting. There have 18 been reports of immunological activity based on elevated 19 IgE, altered T-cell cytokine levels, hyperresponsive nasal 20 eosinophils, and enhanced immunological reaction to common 21 allergens. 22 Most of this information was obtained actually as 23 a result of comments made by the panel in October, and a lot 24 of these reports were published in 1996, '97, '98. 25 Also have been some occupational case reports PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 38 1 suggesting asthma. 2 Unfortunately, we can't really quantify the 3 exposure concentrations that cause these results. 4 Next slide. 5 There's also been some corroborative animal 6 studies done where we have either inhalation or direct 7 application in the respiratory tract which induced airway 8 changes, lung function changes, increased susceptibility to 9 lung infection, and also a number of reports suggesting 10 immunological activity based upon, again, elevated IgE, 11 altered circulatory cytokines, eosinophilic infiltration and 12 inflammation of the airways. 13 So that's the acute summary. 14 With regards to the chronic non-cancer summary, 15 again this information has not been considered that 16 controversial in terms of what we've reviewed and what we've 17 proposed. 18 In terms of chronic non-cancer health effects for 19 the humans, there are some occupational exposure studies 20 that suggest some respiratory effects, but the data are 21 insufficient to calculate a reference level. 22 Instead, we've taken the same route as US EPA and 23 the World Health Organization using animal data, and in this 24 case there's an inflammatory and histological changes in the 25 lung reported above 460 micrograms per cubic meter in the PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 39 1 rat exposed for 30 months. That's the basis of our study. 2 And the next slide it just shows how we did our 3 calculations. We used what's called benchmark dose 4 approach, which is kind of a new approach that's used in 5 non-cancer risk assessment where instead of simply taking 6 the no-effect level, you extrapolate to some percent 7 response. And in this case you can see under the column 8 with analysis percent response was either 1, 5 or 10 percent 9 response. 10 And we used two different models, a probit and a 11 Weibull. You can see the benchmark concentration is then 12 treated like a no-effect level in the rat. 13 And then an uncertainty factor is added and our 14 uncertainty factor in this case would be 30, and then you 15 come up with reference levels in the range of 3 to 21, or 2 16 to 21. 17 But that's the basis of our non-cancer risk 18 assessment. 19 The next slide sort of compares with what we did 20 with other agencies. 21 US EPA has had in their IRIS database and also 22 they've reiterated it in their most recent 1998 February 23 document, a reference concentration of five micrograms per 24 cubic meter. It's based upon the same chronic 25 histopathological changes in the female rat. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 40 1 And the World Health Organization also conducted a 2 series of analyses similar to the kind of thing I just 3 showed you. They had a range of two to 14 micrograms per 4 cubic meter. 5 I also wanted to point out that US EPA also has a 6 PM 2.5 standard, a 15 micrograms per cubic meter, because 7 there was some questions as to how the standard relates to 8 these results. 9 And as I mentioned, our approaches come up with a 10 range of two to 20. 11 So consequently we're recommending to agree or go 12 along with what US EPA presented to come up with a reference 13 level of five micrograms per cubic meter. 14 ACTING CHAIRMAN FROINES: That's assuming a 15 threshold and a 30-fold safety factor? 16 DR. ALEXEEFF: Yes. It's a 30-fold safety factor, 17 assuming a threshold. 18 DR. WITSCHI: How did you come to the 30? 19 DR. ALEXEEFF: The 30, okay, the 30 is broken down 20 into two parts. Usually when we're extrapolating from 21 animals we consider differences between the animal species 22 and the humans. And sort of the first step is to consider a 23 tenfold uncertainty factor. 24 Now, in this particular case there is also some 25 data in the monkey suggesting that although it's not as PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 41 1 quantitative as this rat data, suggesting that maybe the 2 species are not that different in terms of response. 3 So in this case we only used a threefold 4 uncertainty factor to go from the rat to the humans. 5 And then the other part of the uncertainty factor 6 is the interspecies differences or differences within the 7 human population. And again the standard approach is to 8 start with ten, and we stuck with ten, and so did US EPA. 9 The reason for that is ten sort of represents kind of the 10 average, healthy individual and -- I'm sorry. You start 11 with the average healthy individual and then you want to 12 also add a factor of ten to protect those that might be 13 susceptible in terms of asthmatics or other chronic 14 respiratory diseases. So we stuck with a factor of ten in 15 this case. So that's the basis of the 30. 16 ACTING CHAIRMAN FROINES: George, have you found 17 that all the sport utility vehicles that are produced after 18 the year 2000 are diesel vehicles and if you found that near 19 freeways that diesel levels are very high, so you were well 20 above your five, how do you assess the range of risk? This 21 is in a sense a threshold value. How do you define dose 22 response? How would you determine the number of people who 23 might be at risk at seven, 10, 20, 50 and a hundred? 24 DR. ALEXEEFF: Well, if the 30-fold factor ends up 25 being a fairly large assumption in this case, and if we go PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 42 1 back one slide or -- one slide, John, you can see that the 2 benchmark concentration you see one, five and ten percent 3 response. So you can see that the one percent response is 4 about three. This is in the rat, though. Okay. And so, 5 you know, and then the five percent response would be a 6 little bit higher. 7 So what one, you know, the best one could do with 8 the data would be to make some sort of correlation with this 9 information. But then the uncertainty ends up being this 10 30-fold uncertainty factor. 11 DR. GLANTZ: George, I don't see where when you 12 said the one percent is three. I don't understand. 13 DR. ALEXEEFF: I'm sorry. One percent results in 14 a number of .17, and then divide by 30. 15 ACTING CHAIRMAN FROINES: For people who don't 16 know about the benchmark, they're essentially extrapolating 17 from data points where you have information. 18 DR. GLANTZ: No, I understand that. It's just I 19 don't understand when you have the one, five and ten 20 percent, are those -- is the one percent, .175 percent is 21 .59 and ten percent is -- 22 DR. ALEXEEFF: Yes. I'm sorry. That column B and 23 C in terms of simplifying the slide, that's actually 24 milligrams per cubic meter, because we're kind of -- the 25 concentration that we started with was much higher, so we're PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 43 1 kind of going down. It's actually there .17 milligrams per 2 cubic meter or 170 micrograms per cubic meter. 3 There's a small time adjustment which actually 4 results in the actual number change in terms of the 5 conventions of the exposure in the rat. 6 ACTING CHAIRMAN FROINES: Why don't you go ahead. 7 I want to take a little time on this, because 8 you're required to make estimates of risk and this does 9 constitute your estimate of risk for non-cancer respiratory 10 effects. And I want to make sure that everybody is aware 11 that there are more numbers in this document than simply the 12 numbers associated with lung cancer risk. 13 DR. ALEXEEFF: Now, in a practical matter, 14 Dr. Froines, the way it would work or the way it does work 15 when we have a reference concentration and there is some 16 exposure and we're trying to compare it with that reference 17 concentration, we use what's called kind of a hazard index 18 approach. So if the concentration is below that five, we 19 feel that there is no issue of concern at all. That's the 20 basis of the approach. 21 Now, if it's above the five, we feel there's an 22 increasing chance of some concern, so it's not -- it's 23 simply sort of reflecting kind of in terms of our procedures 24 where we would start, you know, having some concerns and 25 depending on -- the concern that we have is in part based PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 44 1 upon how large the uncertainty factor is. So in this case 2 the uncertainty factor is relatively large. So like a 3 factor, like a value of six or something like that would not 4 be of great concern in terms of the uncertainty, but a value 5 of 50 would then of course be of concern. 6 ACTING CHAIRMAN FROINES: All right. 7 DR. ALEXEEFF: Now, I'd like to briefly review the 8 genotoxicity. And the genotoxicity itself I don't consider 9 that to be a very controversial issue in a sense, but there 10 is this related issue of the bioavailability of this 11 genotoxicity. And I'll be getting into that, but I thought 12 I should just briefly go through the genotoxicity 13 information. 14 I presented almost the same slides in October. 15 ACTING CHAIRMAN FROINES: Go quickly then. 16 DR. ALEXEEFF: Whole diesel exhaust and diesel 17 extracts were reported mutagenic in bacterial assays. 18 Particles and extracts of diesel exhaust were reported 19 mutagenic in mammalian cell assays. We have diesel exhaust 20 extracts reported to be mutagenic in cultured human 21 lymphoblasts. 22 Mutagenicity per microgram was not significantly 23 different between the new and the old fuels. We had some 24 discussion about the information is basically preliminary. 25 Diesel exhaust extracts induced chromosomal PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 45 1 aberrations in mammalian cell assays, but most of the 2 results were negative in vivo. 3 The particles in extracts induced sister chromatid 4 exchanges in mammalian cell assays and the results in vivo 5 are mixed. 6 Now, treatment of mammalian cells in vitro have 7 resulted in an increase in the DNA adduct formation. 8 And rats and monkeys exposed to whole diesel 9 exhaust demonstrated an increase in DNA adducts formation 10 and their increased levels of DNA adducts have been found in 11 some workers exposed to diesel exhaust. 12 Now, in terms of bioavailability, the DNA adduct 13 work that I just mentioned is very difficult work and there 14 are some uncertainties in that work and some differences of 15 opinion. 16 But I'll briefly go through why we feel that there 17 is evidence, and we our provide this in the report, why we 18 think there is evidence that the genotoxicity in the 19 particles is bioavailable, even from a mechanistic point of 20 view, aside from the cancer impact. 21 The particles, when the particles are dispersed in 22 simulated pulmonary surfactant, there exhibited similar 23 genotoxic activity to regular diesel exhaust extracts in 24 vitro. 25 The reported adduct formation in rats and monkeys PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 46 1 exposed to diesel exhaust are supportive, but there have 2 been, as I mentioned, some questions of these results in 3 literature, but we feel that it is supportive. 4 Rat tissue exposure to diesel exhaust induced 5 unscheduled DNA synthesis, and so when I say diesel exhaust, 6 I'm saying it's a difficult experiment to develop where you 7 are actually exposing an in vitro study to diesel exhaust, 8 and that's why I mentioned that. 9 DNA adducts associated with some occupational 10 exposures to diesel exhaust, there are some urinary 11 metabolites of polycyclic aromatic hydrocarbons found 12 following exposure to rats to diesel exhaust. Also urinary 13 metabolites of polycyclic aromatic hydrocarbons have been 14 associated with some occupational exposures to diesel 15 exhaust. Thus, the genotoxic components of diesel exhaust 16 particles appear to be bioavailable, but more study in this 17 area would be useful. We think this would be a great area 18 to continue doing more research. 19 DR. BLANC: George, I have a question, just a 20 process question for you. 21 And we have a printout of your slides. 22 I think because this goes over material that is 23 available to us in the report, I think if you will simply 24 highlight briefly any areas where you believe the data 25 you're presenting this morning represents a significant PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 47 1 change or advancement on the February draft document, I 2 think that would be a more useful approach, because I think 3 the panel is familiar enough with much of what you're going 4 over that it's really not productive, I think, to go into 5 this level of detail. 6 DR. ALEXEEFF: Okay. I'd be happy to. 7 ACTING CHAIRMAN FROINES: George, I was going to 8 say, remember, that we've seen it in October, we saw it in 9 March, we've read the document, and I think we need to move 10 so that we can be more active participants. So, for 11 example, I would just leave out the animal cancer data. 12 DR. ALEXEEFF: Fine. 13 ACTING CHAIRMAN FROINES: And Melanie is going to 14 have to be very short on the comments, I think. 15 DR. MARTY: I am very short. 16 ACTING CHAIRMAN FROINES: Because I think 17 otherwise people are going to -- does everybody agree with 18 that? 19 DR. FUCALORO: I agree. 20 I have a question on some of this, I'll certainly 21 pipe up. 22 DR. ALEXEEFF: I think one thing that's worth 23 noting in terms of animal cancer findings is the result in 24 the US EPA report. So I just bring your attention to that 25 quote in there. No sense reading me quotes, but I'll just PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 48 1 bring your attention to that. 2 DR. GLANTZ: What quote is that? 3 DR. ALEXEEFF: It's their findings about the issue 4 of mice. The US EPA feels that the mice data is also an 5 important consideration in the animal carcinogenicity. 6 Now we'll get to the cancer epidemiology slide. 7 As we mentioned before, we reviewed many studies. 8 I just want to emphasize that there seems to be some 9 confusion from time to time that we've looked at many 10 studies, including those of not just railroad workers, but 11 also truck drivers, dock workers, transport workers, 12 equipment operators, to name some. 13 The next slide. 14 And we assess the quality of this information both 15 qualitatively and quantitatively. We've gone through the 16 what's considered the Bradford Hill criteria in terms of 17 consistency, possibility for bias and chance, evidence of 18 exposure response, temporality, biological plausibility. 19 The issue of causality has been one that remains 20 in the comments, so it's important to take this into 21 account. 22 So the key issue here is that there's a lot of 23 consistency. We feel the explanation in terms of bias or 24 chance is unlikely. Evidence of exposure response is sort 25 of the weak point. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 49 1 Getting back to the strength of the findings, it's 2 a fairly weak association, about a 40 percent increase. 3 Temporality association is appropriate and the 4 biological plausibility, we think, is definitely there. 5 And on the next slide this is from the document. 6 Smoking-adjusted studies of diesel exhaust exposure in lung 7 cancer, and in this list again there are in addition to 8 railroad worker studies, there is also truck drivers, dock 9 workers, equipment operators. 10 And you can see the consistency by looking at just 11 the midpoint. Some of the studies are not statistically 12 significant. The far -- the point on the far right is the 13 result of the meta-analysis, the all smoking-adjusted value. 14 And then if we go to the next slide. 15 DR. FRIEDMAN: George, there was a point in the 16 middle with very narrow confidence bounds. Was that a 17 meta-analysis too or -- that is a very large study. I think 18 it was Pfluger. 19 DR. ALEXEEFF: I can't recall. 20 DR. FUCALORO: It's almost identical to the 21 meta-analysis. 22 DR. ALEXEEFF: Which, can you read that? 23 DR. FRIEDMAN: Pfluger, 1994. 24 DR. ALEXEEFF: The question, Dr. Lipsett, was from 25 Dr. Friedman, was that an actual meta-analysis or was it PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 50 1 actually a study of workers? 2 And I think that was the question you were asking; 3 right? 4 Dr. Michael Lipsett. 5 DR. LIPSETT: It is from one of the studies that 6 was part of the meta-analysis. The summary estimate is over 7 at the far right of the graph. 8 DR. FRIEDMAN: Was it a huge study, is that why 9 the confidence levels are so narrow? 10 DR. LIPSETT: Okay. It was -- it wasn't a huge -- 11 it wasn't necessarily a huge study. It was about 1300 12 people. 13 DR. FRIEDMAN: Well, I mean, this is not a real 14 important point, but I just wonder if there's not mistake in 15 putting -- because it just doesn't seem right that a study 16 would have such narrow confidence limits. 17 DR. LIPSETT: I can certainly check it on the 18 spreadsheet, but we did have an error-checking procedure in 19 terms of data entry, and having a couple people look these 20 things over. I don't think it's a mistake. 21 DR. FRIEDMAN: By the way, I appreciate, I think 22 the previous version had this expressed as logs of relative 23 risk, and I appreciate that you made that change to actual 24 relative risk. I think it's much more understandable now. 25 I just have one minor suggestion that I don't PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 51 1 think should hold up our approval. I think that perhaps in 2 the next version that although you now don't have it 3 expressed in logs, you should still use a log scale, because 4 it's -- you're talking about a multiplicative type of 5 situation. 6 And then the confidence limits would be 7 symmetrical. In other words, from .5 to 1 should be the 8 same distance as from 1 to 2, and 2 to 4, and so on. 9 DR. LIPSETT: Okay. 10 ACTING CHAIRMAN FROINES: Go ahead, George. 11 DR. ALEXEEFF: And this slide just simply 12 quantitates that the point on the far right side, it's 1.44 13 using a fixed effects model, and 1.43 using a random effects 14 model. And this is again the smoking-adjusted values taken 15 from the studies that took -- that adjusted for smoking. 16 The next slide. 17 And again in the human cancer findings, the early 18 findings by IRAC had limited evidence. US EPA, in their 19 most recent document, has moved further than that and is now 20 saying that the human evidence is highly suggestive of an 21 association, and it's just short of being labeled as a known 22 human carcinogen. 23 And the next slide mentioned before about HEI and 24 WHO's conclusions, that they do see a weak association, weak 25 meaning about a 40 percent increase. And at the same time PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 52 1 HEI feels that their conclusions should be always couched by 2 the fact that they feel the uncertainties and confounders 3 prohibit the use of this information for quantitative risk 4 assessment. And that is a difference of opinion, but I just 5 like making that clear. 6 ACTING CHAIRMAN FROINES: Is that true in Aaron 7 Cohen's chapter? 8 DR. ALEXEEFF: I don't think Aaron Cohen's chapter 9 specifically addresses application of this to quantitative 10 risk assessment, but it could very well be. 11 Okay. In terms of our conclusion, our conclusion 12 and our document is that the epidemiologic studies provide 13 evidence of a consistent and causal relationship. 14 The next slide. 15 Now, I'd like to -- this is pretty much the issue 16 of greatest contention, concern, both in the comments and by 17 people looking at our document, how we did the quantitative 18 risk assessment, what we used, so I'm going to go through it 19 and also try to put it in a little bit of perspective. 20 First of all, Kathy Hammond, Dr. Hammond, made a 21 presentation last month to the panel discussing the 22 exposures of different worker groups, all the way from heavy 23 equipment operators, truck drivers, bus drivers, railroad 24 workers. 25 And she presented to the panel this range, this PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 53 1 exposure range of 5 to 500 micrograms per cubic meter. She 2 felt that that kind of covered the whole range. And that's 3 in the slides that she provided. 4 At the same time in October the panel had asked us 5 to think about using this meta-analysis information somehow 6 in a risk assessment. And we felt that we -- that it could 7 be used to give us a sense of the total bracket of risk, but 8 not necessarily the range of risk that we would propose, 9 primarily because the exposure range in all those different 10 occupational groups is such a broad range. 11 You can see that it brackets the risk from about 12 1.3 in 10,000, to 1.3 in 100. So that's kind of like the 13 conceptual approach that we were using that basically the 14 meta-analysis and the total range of exposure that it's 15 possible in the studies, what would the range of risks kind 16 of be or the bracket of the risk. 17 We did an in-depth evaluation of two railroad 18 worker studies. One is the Garshick case control and the 19 other is the Garshick cohort data. 20 It's the Garshick cohort data that's had all this 21 extensive discussion and re-evaluation. 22 And, again, the primary source of uncertainty that 23 we feel exists is the exposure data in these worker studies. 24 In the next slide what we did is we considered 25 various scenarios of exposure to try to bracket what's the PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 54 1 possible range of exposure of these workers, again to get a 2 full breadth of what the range of risk could be, because our 3 primary responsibility is to come up with a range of risk. 4 The first, I presented this slide in the October 5 meeting, but I think it bears repeating, because it can get 6 to be a little bit confusing. 7 The first slide is what's called, what we're 8 referring to as a block exposure pattern. That's just 9 assuming constant exposure from 1959, and that is how the 10 Garshick studies are constructed, just assuming constant 11 exposure. 12 Later on in 1991 it was suggested that the 13 dieselization that occurred from the mid '40s to '59 be 14 taken into account, and so a ramping kind of approach came 15 into fruition. 16 And in the bottom, number C, that is what we are 17 referring to as a roof pattern, and roof is just descriptive 18 of a picture, and that takes into account the rate of 19 dieselization, plus the improvements in engine design and 20 engine efficiency that occurred after 1959. 21 We have both some anecdotal information in these 22 railroad worker studies, as well as some information that we 23 received from the Engine Manufacturers' Association and 24 received it from the, I think, the Railroad Workers' 25 Association, or some railroad association that was studying PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 55 1 engine design. So we know that there has been some 2 improvement in the emissions. 3 DR. WITSCHI: I have a question with regard to 4 this. 5 The way this looks superficially is if these 6 people are in pristine air and then from '59 all of a sudden 7 they are exposed to diesel, do we have -- that's probably 8 not true. I mean, they were working in railroad yards and 9 there must have been considerable other things around before 10 diesel came along. Do we have any idea about what was 11 around before diesel came along or still together with 12 diesel? 13 DR. ALEXEEFF: Well, yes, there's two issues here. 14 One is dieselization that was occurring, so if we 15 went with the top diagram, which we do not in our report, 16 but if we went with the top diagram it would not take into 17 account the diesel exposures that occurred before '59, so we 18 actually support the bottom diagram, number C. 19 But what you're saying is other compounds in the 20 air that would be contributing to risk and exposure, okay. 21 And that is definitely would be a concern in any of these 22 exposure studies, other confounders. 23 Part of it is taking into account not in terms of 24 the response, but at least in the exposure in the way that 25 Dr. Hammond and others subtracted out some of the other PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 56 1 things that they were in the air, and particular 2 environmental tobacco smoke and other -- there's other 3 background concentrations of particulate matter that are 4 subtracted out in the calculations. 5 Now, in terms of whether there is some other 6 substance or component in the air which is causing the 7 disease, some of the studies try to take some issues into 8 account. For example, I think one of the Garshick studies 9 tried to take into account asbestos. 10 But, you're right, this is an issue of 11 uncertainty. 12 DR. WITSCHI: What about steam engines? They were 13 pretty dirty. 14 DR. ALEXEEFF: Yes, I agree. 15 So you do have that confounding. 16 In a sense you have other exposures which are not 17 taken into account, but what you try to do, and I can 18 have -- well, maybe I should have Dr. Lipsett explain how 19 the study designs of these epi studies try to focus on the 20 diesel exhaust component in terms of their structure. 21 Did you want to make any comment? 22 ACTING CHAIRMAN FROINES: I will say, George, just 23 one comment, as a person who is an exposure assessor in 24 occupational epi studies, that it seems clear to me that if, 25 one, if you put together a group of industrial hygienists PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 57 1 who do this kind of work, like Bob Spear or Steve Rappaport 2 and Tom Smith and others, I think the roof model makes the 3 most sense. It makes the most sense for two reasons. 4 One of which was in 1970, when the OSHA act was 5 passed, people's attention to chemical exposures became much 6 more heightened and it's very clear that during that decade 7 of the '70s to the '80s, as a uniform phenomenon, exposures 8 went down. 9 So I think it's one could argue about the slope of 10 the decline, but I think it's clear that there was a decline 11 in exposure. 12 And so it seems to me that using the ramp with 13 then a flat exposure is probably going to estimate what was 14 one of the most health, occupational health conscious 15 decades in the last hundred years, and so that I think the 16 roof model tends to reflect what the industrial hygiene 17 community would recognize during that decade more than you 18 might otherwise realize. 19 DR. LIPSETT: I just wanted to add a couple 20 things. 21 First, a correction to what I said before to 22 Dr. Friedman. I haven't read this particular paper in many 23 months and went back, I was looking at the wrong thing when 24 I indicated there was that. There was actually well over a 25 million person years of exposure involved in that one study PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 58 1 and that will explain why the confidence interval is so 2 narrow. 3 So I hope that allays your concern about an error 4 in that. 5 DR. FRIEDMAN: Thank you. 6 DR. LIPSETT: One of the other things, though, 7 with respect to steam engines is apparently one of the main 8 concerns that took place during the steam engine era was 9 asbestos exposure when these things were overhauled and the 10 number of the railroad studies did try to take that into 11 account where they had information about exposure to 12 asbestos during that period of time. 13 And then with respect to the emissions from the 14 steam engine, in at least one of the railroad studies found 15 the investigators did try and look at the effects of that 16 separately by using certain brackets on the time of exposure 17 and found that the relative risk from that was not -- I mean 18 it wasn't substantially greater than what you would see from 19 the diesel exposures occurring later. 20 That's not very helpful. The data are pretty 21 sparse, basically. 22 ACTING CHAIRMAN FROINES: Is there any data within 23 the studies on mesothelioma, which would be indicative of 24 confounding by asbestos? 25 DR. LIPSETT: Yeah, I think there was in at least PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 59 1 one of the studies, but again it's been many months since 2 I've read most of these studies and I -- 3 ACTING CHAIRMAN FROINES: But it's not something 4 that you feel was a major issue? 5 DR. LIPSETT: No. 6 DR. KENNEDY: That was not generally recognized 7 before 1948, so it would be hard to come up with anything 8 before that. 9 ACTING CHAIRMAN FROINES: He's looking at people 10 who are dying later. The Selecoff stuff is in the early 11 '60s, so there's from the '60s on there's a consciousness 12 about mesothelioma. So I would guess that they would -- 13 DR. KENNEDY: I thought the question relates to 14 the awareness of mesothelioma and a time context. It was 15 not described by Selecoff until around 1950. 16 ACTING CHAIRMAN FROINES: He's saying that for the 17 pre-diesel period, that there was asbestos, people might not 18 have recognized it. 19 DR. LIPSETT: There's one study, though, the one 20 Finnish study, that seemed to have a lower risk for lung 21 cancer and it did find a substantially increased risk for 22 mesotheliom in the train engineers that they looked at. It 23 was severalfold increase in mesothelioma. 24 ACTING CHAIRMAN FROINES: That in your study or 25 your meta-analysis? PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 60 1 DR. LIPSETT: Is that paper? It is included in 2 the meta-analysis, but the mesothelioma is not, just the 3 lung cancer. 4 ACTING CHAIRMAN FROINES: But it becomes a clear 5 confounder then. 6 Let's go, George. 7 DR. ALEXEEFF: We agree with you, Dr. Froines, 8 that the roof pattern is the most appropriate. 9 Now, this table is taken from the document and you 10 can see, I'd like to just explain what this table represents 11 because this ends up being sort of the crux of a lot of the 12 discussion or concern. And again I have Dr. Dawson here if 13 we have any specific questions on the derivation of these 14 numbers. 15 First of all, just to point out we have risk 16 estimates that are derived both from the case control study 17 as well as the cohort study, and it's the cohort study that 18 has had a lot of additional concern and a lot of the 19 discussion of the comments refers to results of the cohort 20 study. 21 Now, you can see in that column of different 22 scenarios. Now, scenario A refers to the ramp pattern. All 23 the other scenarios refer to that roof or that peak shaped. 24 So it's just something to point out. 25 The ramped pattern has the highest risk, because PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 61 1 it ends up being the lowest exposure. Okay. Because it 2 doesn't come back down. So that's something to keep in mind 3 as to whether or not the ramp pattern is appropriate to keep 4 in the range of risk. 5 So the other scenario is B, C, D and F are all 6 scenarios on the roof pattern, but the differences have to 7 do with what Dr. Froines mentioned about the slope of that 8 roof pattern. 9 No. E, which has the lowest risk, has the highest 10 peak. It goes all the way up to 500 micrograms per cubic 11 meter in 1959, and then it goes all the way down to 50 12 micrograms per cubic meter. It has the -- it presumes the 13 highest exposure of the railroad workers, and therefore 14 results in the lowest risk. 15 And then the others, B, C and D represent 16 modifications of those peak levels. 17 And we think that from B through E we've pretty 18 much captured the information that Dr. Hammond presented 19 last month in terms of what are the possible -- what's the 20 possible range of exposure that could have occurred in terms 21 of these workers here. 22 And also Dr. Hammond suggested that this 23 information could be applied to both the case control, as 24 well as the cohort study, the exposure information, and that 25 is what we have done here. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 62 1 Now, the other thing is -- 2 DR. BLANC: George, one of the modeling 3 assumptions that's missing from this table, and may be 4 confusing to other people, is that the block pattern is 5 missing, which gives yet the highest estimated risk, and the 6 risk value of 2.4 times 10 to the minus 3rd, which it 7 doesn't appear here, is in fact based on the block 8 assumption; is that correct? 9 DR. ALEXEEFF: Correct. Yes. If one chose to 10 make a calculation based upon the block diagram, as 11 Dr. Blanc indicated, there would be slightly higher risk. 12 It would go above the A value or above the scenario A, be 13 somewhere around 2 to 3. So it increases it. 14 DR. BLANC: In fact, isn't that the risk number 15 that's cited later in the document? 16 DR. ALEXEEFF: Yes. There are other 17 investigators, and I'll mention that on my next slide or so, 18 sort of putting it into context, numbers that have come out 19 of the study using the block diagram. That's basically the 20 approach they use. They used a constant exposure from '59, 21 so it makes for a slight higher risk. 22 DR. BLANC: What I guess I'm trying to say, 23 wouldn't it be useful for this table, depending on how this 24 table would be used, to at least have in the legend or 25 underneath the table, the clarification that is not listed PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 63 1 here is the block scenario, which would yield for the case 2 control a value of X and for the cohort a value of Y? 3 DR. ALEXEEFF: What we want this -- what we would 4 like this table to show is the range of risks being 5 proposed. 6 And Dr. Froines at the last meeting suggested that 7 we have an additional table, which shows all the risk values 8 calculated by various investigators. So I will mention that 9 and I think that's one proposal is to add. 10 We have the information in the document, but 11 because the text can be difficult to sort of wade through, 12 it was suggested we put it in a table. So I think that 13 might be where it could be clarified. 14 ACTING CHAIRMAN FROINES: Let me make my point 15 here, and I feel extremely strongly about that. 16 And, Paul, I think what you're asking for is 17 exactly what I want in the end, which is a full table that 18 covers all the risk assessments that have been done, and put 19 in some sort of orderly form so people can read it. I mean, 20 putting things in a table is supposed to make things easier, 21 not harder. 22 But for example, in a previous slide, you've 23 already shown a risk assessment. You've shown Michael 24 Lipsett's meta-analysis and Kathy Hammond's, and estimates 25 of exposures that occur, and you've come up with numbers PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 64 1 from that. 2 And so that is a value that's already been done. 3 That's separate from the Garshick data. 4 DR. ALEXEEFF: Correct. 5 ACTING CHAIRMAN FROINES: And I want everybody to 6 see that in fact, and we're going to come to this when I get 7 into the NIOSH data later, that we have some very strong 8 risk assessments that have been conducted that are not only 9 linked to the Garshick information. I want to show the 10 breadth of the risk assessments so people have some sense of 11 the complementarity between them and have a sense of how 12 people approach them. 13 So these are railroad workers and NIOSH workers on 14 truckers and so on and so forth. 15 DR. GLANTZ: My understanding, I agree that there 16 are places that you just get bogged down in this report, and 17 my understanding is that nobody thinks the block pattern is 18 a realistic exposure pattern. 19 DR. BLANC: Well, that's what the EPA is using for 20 their risk estimate. 21 DR. GLANTZ: Oh, really? 22 DR. BLANC: Of course, one question that is a 23 really minor one, but I was just curious, maybe, Mike, you 24 have the answer to this, if we have a number of 2.4 using 25 the cohort -- using, I'm sorry, the case control data and PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 65 1 the block assumption, and EPA has a value of 2.0, I'm just 2 wondering maybe Dr. Dawson can comment why there's that 3 slight mathematical difference, since I assume that's a 4 modeling using all the same assumptions. 5 ACTING CHAIRMAN FROINES: But also, Paul, we can 6 have in the table the EPA estimates again to show the 7 ranges. 8 DR. BLANC: I think they are in essentially that's 9 what this Table 3 is, which I guess George is going to get 10 to. 11 ACTING CHAIRMAN FROINES: Well, I don't think it 12 has the EPA data in it. Maybe it does. 13 DR. GLANTZ: If I can just maybe finish a point I 14 was trying to make, and maybe I should drop it, but I was 15 going to suggest that the discussion of the block pattern be 16 just dropped in the report, because I think it's confusing. 17 DR. BLANC: Well, I wouldn't, because I think you 18 want to show that you've addressed and related to the other 19 risk estimates that are out there. 20 ACTING CHAIRMAN FROINES: If EPA has it, we can 21 put it in a table and have a footnote that says based on a 22 block. 23 DR. GLANTZ: Okay. 24 ACTING CHAIRMAN FROINES: Now, the other thing is 25 that there's one thing that George and I talked about and PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 66 1 the panel can discuss it later, I don't think we have to 2 discuss it right now, but the EPA document used a unit risk 3 value of 2 times 10 to the minus 3, and we have no values 4 that have more than two places past the decimal. It might 5 be useful to get rid of anything past the decimal and just 6 go with the number. 7 DR. BLANC: Well, they -- 8 ACTING CHAIRMAN FROINES: Like 7.0 to 7.6, how we 9 want to deal with that. Do we want to just treat that as 7 10 and go with it? 11 But let's not take that up right now. We're 12 thinking about it. 13 DR. WITSCHI: But I have problem with the Table 3 14 and with the next two slides that George is going to show, 15 because if you -- it gives a so-called overview about the 16 different risk estimates. There were only two sets of data 17 those different estimates were derived from. 18 The one is the comparative mutagenesis studies, 19 which is always the same set of data is looked at it another 20 way, and the other one are the railroad workers, and they 21 also looked at it in different ways. 22 The need, the important thing is the paucity of 23 data, but there are numerous way to look at those data. 24 But this doesn't exactly confirm that the database 25 is assumed. Just because you can manipulate it in very PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 67 1 different ways does not necessarily mean the different 2 analyses confirm each other and strengthens the evidence. 3 ACTING CHAIRMAN FROINES: I think that's an 4 important point, Peter. 5 Let's come back to it when we go around the panel 6 and talk about that as a substantive issue, because one 7 could make the opposite argument that there is consistency 8 within the data and that's good, and that the approaches 9 that have been taken are different approaches. 10 The meta-analysis is not based on the railroad 11 worker study. The NIOSH data is not based on the railroad 12 worker study. So we have more than -- we have at least 13 three risk assessments based on different data sets. 14 So let's come back to that. 15 DR. WITSCHI: Wait a second here. This table says 16 for this meta-analysis, says based on smoking-adjusted 17 pooled railroads. 18 DR. BLANC: Well, relative risk, not railroads. 19 DR. WITSCHI: Relative risks. 20 DR. BLANC: Yes, that's fine. 21 Also, Hanspeter, it's important that you note that 22 in fact these relative -- I'm sorry, these risk estimates 23 are not based, even the ones that cite Garshick, are not 24 based all on the same studies, they're based two different 25 studies. One is a case control study and one is a cohort PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 68 1 study. So I would actually differ with your interpretation 2 that it's a different analysis of the same data, because 3 it's analyses of different data and data obtained with a 4 fundamentally different methodological approach, and 5 therefore coming up with similar estimate ranges using two 6 different studies, albeit in the same general work 7 population, using very different methods of obtaining the 8 data are quite supportive, one of the other. 9 So, actually, I wouldn't agree with your comment 10 in that regard. 11 ACTING CHAIRMAN FROINES: It's an important point, 12 and let's come back to it. 13 DR. BLANC: I think that, Dr. Dawson, you were 14 going to just clarify for me that 2.0 versus 2.4. I don't 15 think this will take you very long. 16 DR. DAWSON: Well, I'll try to be precise. 17 I'm Stan Dawson. 18 First of all, the US EPA number is based on 19 McClellan's analysis of the case control. 20 DR. BLANC: Right. Case control study. 21 DR. DAWSON: Right. And he's making two 22 assumptions there about the level of concentration which he 23 considers to be constant from 1959 to 1980. And the two 24 assumptions are 125 micrograms per cubic meter and 500. 25 Now, the higher risk number, of course, comes from PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 69 1 the 125, so that's where that came from. 2 Now, we do not -- that's just -- and this report, 3 in the previous report, we used that number, the previous 4 draft last year. 5 But in this report we do not use that number at 6 all. We simply go back to the Garshick case control slope 7 result, and put in our -- an extended block scenario. 8 Now, it goes back from seven years prior to 1959, 9 because we think that it's really more like a ramp than a 10 simple block, but it has the same cumulative area under the 11 curve, the same cumulative exposure as the area under the 12 curve, as that particular block, and the block is more 13 logical for a duration analysis, which is what Garshick's 14 case control study, how that was analyzed. 15 So, anyway, we put that extended block in and then 16 did the basic calculation up there in A, which gives you 17 this same number that you get if you used the ramp, and then 18 I did the ratioing process to get all those other numbers 19 out, simply erasing the area under the curve of each 20 scenario compared to that original block. 21 ACTING CHAIRMAN FROINES: The people doing the 22 video want to take a break, but I'd like George to go 23 through your next -- can you get through the risk 24 assessments and we need to take a break. 25 DR. ALEXEEFF: Yeah. I'd be happy to. It's not PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 70 1 that much further in terms of just putting in perspective. 2 If you look at the next slide, and I put a 3 handout -- I broke it down into two pieces so that it would 4 show up on the overhead, but this is the handout in the 5 back. 6 And also I think the panel members should have 7 this handout, which just lists various reports that have 8 reported unit risks, and also includes the numbers that 9 constitute our range are listed in bold. 10 So you can see the top, and there's the method 11 description. 12 The first three are this comparative potency 13 analysis, where one is comparing the potency of diesel 14 exhaust relative to some other carcinogens. 15 And then the other first epidemiologic analysis is 16 the one that Dr. Smith presented and slightly refined, he 17 presented it was last month. 18 And then it's -- then you can see ours in bold. 19 If you go to the next slide, John. 20 Now, I've added the information in red there from 21 the -- just to let you see that this is information that 22 probably could be added. It's in the -- came in the Federal 23 Register this month. There's a survey of ranges from 24 Dr. Stayner, and that goes from one in -- you know, right 25 there you can see the range there. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 71 1 And then there's a new study which is in press by 2 Dr. Steenland, at NIOSH, on US truck drivers, and reports 3 that range, or that value there. 4 And I put it, it's sort of in the middle -- those 5 numbers are kind of overlapping our range somewhat. 6 And then you can see further down in the non-bold, 7 other studies. There's the railroad workers, London 8 transport workers, US EPA's slight modification use of the 9 McClellan data, and then our bracketing approach that we 10 used on the bottom. 11 So it gives you a sense as to where the 12 calculations we did can kind of be placed with other 13 calculations that will be done, just on the human data or 14 some variation of the human data. This does not include the 15 animal data. 16 ACTING CHAIRMAN FROINES: So it looks to me like 17 at the widest range you're running 1.3 times 10 to the minus 18 2 up to what? 19 DR. ALEXEEFF: Roughly 2.6 times 10 to the minus 20 5. It's on the previous slide. 21 DR. FUCALORO: It's not on this one. It's on the 22 previous one. 23 ACTING CHAIRMAN FROINES: So we're running, what? 24 DR. ALEXEEFF: About 2 in 100,000. 25 ACTING CHAIRMAN FROINES: 2 times 10 to the minus PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 72 1 3. 2 DR. ALEXEEFF: 2 times 10 to the minus -- no, the 3 smallest number is roughly 2.6 times 10 to the minus 5. 4 Okay. That's the smallest risk. 5 And then the largest risk is -- well, there's 2 to 6 the minus 3, and then there's the bracketing which goes even 7 further. 8 ACTING CHAIRMAN FROINES: Which is? 9 DR. ALEXEEFF: 1.3 times 10 to the minus 2. 10 DR. GLANTZ: Yeah, but you know if you limit 11 yourself to the epidemiological studies, which I think this 12 is the more cautious thing to do, then the range is even 13 narrower. It's around 2 times 10 to the minus 4 to around 2 14 times 10 to the minus 3. 15 ACTING CHAIRMAN FROINES: Which epidemiology 16 study? 17 DR. GLANTZ: If you just look at all of them. 18 I'm looking at the table. 19 The comparative potency, I think the epidemiologic 20 analysis is going to be more -- there's more or less 21 uncertain than the comparative potency analyses and if you 22 just look at the epidemiological studies, the range of unit 23 risk is about an order of magnitude, and we're just 24 eyeballing it from around 1 or 2 times 10 to the minus 4 to 25 around 2 times 10 to the minus 3. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 73 1 ACTING CHAIRMAN FROINES: George, I mean, Stan, I 2 think that's a point to take up, which is whether or not to 3 use the comparative potency, and I tend to agree with you 4 that those are less solid than the other studies we have 5 before us. 6 So let's hold that. We've got a couple of topics 7 we want to hold. 8 So, George, is this -- but I think the important 9 issue here is that we see a range of values, we see a range 10 of approaches and we see a range of populations that have 11 been under study. So this gives us in a sense the landscape 12 on the quantitative risk assessment issue for us to then 13 talk about as part of our deliberations. This gives us a, I 14 think, a wider picture than what we had in the documents 15 that only listed basically the Garshick report. 16 DR. BLANC: Can I ask a question about the 17 Steenland data that have just -- are just coming out or in 18 press, in the American Journal of Industrial Medicine? In 19 addition to the quantitative risk estimate derived from that 20 study, does that study have a relative risk estimate that is 21 not previously been calculated on that cohort or did they go 22 back to data that has already produced a relative risk for 23 lung cancer that has already been incorporated into the 24 meta-analysis? 25 Maybe Mike can answer that question, Mike Lipsett. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 74 1 DR. ALEXEEFF: I think maybe during the break we 2 can check. 3 DR. BLANC: Okay. 4 ACTING CHAIRMAN FROINES: George. 5 DR. ALEXEEFF: And this last slide just, I think 6 it's on the key points with regards to the requirements in 7 the statute. There is the reference concentration for 8 non-cancer chronic exposure of five micrograms per cubic 9 meter. 10 We're supposed to make a statement whether or not 11 we were able to identify a threshold, and obviously we 12 identify a threshold for the non-cancer effects. We're 13 unable to identify a threshold for the carcinogenic effects. 14 And then the bottom point simply is the range of risk based 15 upon our epi studies in that table, Table 1-1. 16 DR. FUCALORO: Just a clarification. 17 DR. WITSCHI: I have a question. 18 DR. ALEXEEFF: This is the range. It's in the 19 current document. Later on we're going to suggest we have 20 some revisions that might modify that range slightly, but 21 this is what's in the current February document that went 22 out. 23 DR. BLANC: So can you just -- can you explain to 24 me again the 1.3 times 10 to minus 4 conforms to the number 25 that I had seen previously, the 1.5 times 10 to the minus 3 PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 75 1 is slightly lower than the 2.4 times 10 to the minus 3. Can 2 you just explain to me again, I think I've lost a step here, 3 where we discarded some of the more potent estimates that 4 were somewhat above 2.0. 5 DR. ALEXEEFF: That is simply a correction from, I 6 think the 2.4 you're referring to is what the previous 7 version -- oh, I'm sorry. Yeah. We're going to be making a 8 proposed correction based upon actual comments submitted 9 which adjusted the 2.4. And Dr. Marty will be explaining 10 that. 11 DR. FUCALORO: So the Table 2 reports it as 1.3 12 times 10 to minus 4, to 2.4 times 10 to the minus 3, and 13 that's the accurate -- 14 DR. ALEXEEFF: I'm sorry. That is going to be a 15 proposed correction. So this is the range that's actually 16 in the document, and then you have a proposed correction on 17 that range. 18 DR. WITSCHI: I have a question. 19 What are we doing with the McClellan study from 20 '89, because that's he repeatedly retracted it. 21 DR. ALEXEEFF: Right. We are not using the 22 McClellan study in our calculations at all. But US EPA is, 23 so we simply included it in that table. US EPA is using it, 24 we are not using it. 25 DR. WITSCHI: I'm wondering whether we even should PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 76 1 mention it, because clearly somebody said that was wrong. I 2 don't know that we can use this. 3 DR. BLANC: Well, I disagree pretty strongly with 4 saying that. I think it's important to recognize what the 5 US EPA is going to be doing as long as it's put in the 6 proper context, which is this document does. 7 DR. WITSCHI: I'm not talking about the US EPA. 8 DR. BLANC: But US EPA is actually basing their 9 risk estimate on the McClellan analysis of the Garshick case 10 control data, and therefore it would be silly of us to 11 completely ignore what the EPA is doing. It should be given 12 a nod, as it is in this document. 13 And maybe I misunderstood your comment, but your 14 comment was let's just not even mention the McClellan 15 analysis, but that, I think, would be inappropriately naive. 16 DR. GLANTZ: Would it be okay to just in the 17 table, the fourth through the bottom line is the McClellan 18 risk number, which if Hanspeter says it's been retracted, 19 couldn't that just be deleted, because if you go down 20 further, the second from the bottom line is the citation to 21 US EPA. 22 ACTING CHAIRMAN FROINES: See -- 23 DR. GLANTZ: I'm just reacting to the comment. 24 ACTING CHAIRMAN FROINES: We all know Roger, and 25 if Roger has published a paper with findings in it and we PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 77 1 review the science within the paper, right? That's our job. 2 Sometimes we don't like that science and sometimes we do. 3 Sometimes we're critical. Sometimes we accept it. 4 But we always interpret every paper we read. 5 That's our job as scientists. No paper is read as though 6 it's God's truth. The way science works is to be critical. 7 We have every obligation to take a paper that 8 Roger wrote and be critical of it. We may decide that it's 9 irrelevant. We may decide that it's a great paper. 10 But we do have the option, and I would argue the 11 responsibility, to look at Roger's paper and make a 12 determination on the adequacy of the science. 13 And I think we have to do that as scientists, 14 because we all do it to each other when we review papers all 15 the time, and I think it's our obligation to do that. 16 And if we simply say that Roger withdraws his 17 paper, he can withdraw his paper, but it doesn't mean we 18 don't get to read it and judge it. We respect him, he's a 19 great scientist, so it's not as though we're saying that 20 what he's doing is incorrect. 21 But I think we still have the obligation to 22 evaluate the data that's in that document. 23 DR. FRIEDMAN: George, the bottom, the 24 epidemiologic analysis listed at the bottom of the table, 25 that's the one that's based on the meta-analysis. Could you PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 78 1 explain why you didn't take -- put that in bold and include 2 that as one of your primary risk estimates? 3 DR. ALEXEEFF: Yeah. There's probably a couple of 4 reasons we did not include it. 5 One is we were simply using it to sort of get a 6 sense as to what's the total possible ballpark landscape. 7 So it's a fairly broad range of exposure of five to 500 8 applied to the various occupational cohorts. 9 I think if one wanted to really do it rigorously, 10 you'd probably want to, you know, choose various exposures 11 for the various subcohorts and apply them, which we did -- 12 which we did not do. But it was just sort of set the 13 landscape. 14 ACTING CHAIRMAN FROINES: George, but that's wrong 15 at one level, isn't it? Because you have taken a wide range 16 and you have looked at the data and you do have a range that 17 runs over a factor of a hundred, which is quite consistent 18 with everything else we've done. 19 Therefore, the fact that you're bringing in the 20 meta-analysis, making an estimate of the range of exposures, 21 if we want to after this is all over, we can go back and 22 look at that range of exposures more carefully and tighten 23 it down and give it some other numbers. 24 But this actually seems to me to be very useful. 25 It's saying we're not -- we're going to look at what the PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 79 1 exposures were known to be and we're going to take a range 2 of those exposures, and we're going to see how it turns out 3 within the context of the meta-analysis. 4 And I frankly think that that -- I don't know if 5 this was what Gary was saying -- but I think that that one 6 meta-analysis risk assessment linkage is actually very 7 valuable. 8 DR. FUCALORO: I'm not sure. You don't mean that 9 this -- you're talking about the last entry here? I'm not 10 sure that's the meta-analysis, if I understood what that 11 means, but rather a range of analysis -- a range of values 12 that you've seen. I think the meta-analysis you're talking 13 about is in the slide you showed previously, the graph, and 14 which had a rather narrow range of uncertainty. 15 DR. BLANC: No, no. Let me explain what they did, 16 because then if I didn't understand it, then you'll know 17 that other people didn't understand it. 18 They did a meta-analysis that gave a relative risk 19 of 1.4, let's say, for the confidence intervals. 20 They know from epidemiologic data that the 21 absolute range of exposures in the various occupational 22 studies was a low of five micrograms per cubic meter and a 23 high of 500 micrograms per cubic meter. And then they went 24 through an algebraic calculation and said let's assume that 25 everybody in all of those studies was exposed to only five PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 80 1 micrograms per cubic meter, and that gave a relative risk of 2 1.4, what would the cancer potency be. 3 And then they said, well, now let's assume that 4 everybody was exposed to 500 micrograms per cubic meter, 5 what would be the cancer potency. So if everybody was 6 exposed to such a high level to get a relative risk of 1.4, 7 then you would get that low level of 1.3 times 10 to minus 4 8 and if everybody was exposed to five, then you'd get -- and 9 that's why the brackets are actually kind of absurd in a 10 sense, because -- and that's why you were so cautious to use 11 the word brackets, but I think there's an easy solution for 12 this problem, which would make it more consistent with all 13 the other confidence interval based data that you presented, 14 which is to make an assumption that the mean exposure was 15 250 micrograms per cubic meter, come up with an estimate of 16 what the standard deviation about that mean of 250 17 micrograms per meter is, and then give us 95 percent 18 confidence intervals for what the upper and lower bounds 19 would be of the cancer potency factor, assuming not the zero 20 percentile, but the fifth percentile, the 95th percentile, 21 and assume that the exposures were normally distributed, 22 even though that's probably not true. 23 And at least then you would get something that 24 would be somewhat less than 1.3 and up to the 10 to the 25 minus 4 and -- it will be narrower on both sides and if you PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 81 1 want to model it with instead of normal distribution, Possan 2 distribution or something, which might even be -- have a 3 narrower peak and lower slopes, that might even be better. 4 What do you say, Stan? 5 DR. GLANTZ: I don't know if we want to have them 6 do it, because I don't think it's going to change. 7 DR. BLANC: It's not going to change the bread and 8 butter of this -- 9 DR. GLANTZ: I think it's a good idea. And I 10 think it will confirm -- I think what that will probably end 11 up doing is giving you a range of risk very similar to what 12 they got from the Garshick data, which would strengthen the 13 case. I don't know that we'd want to hold the report up -- 14 maybe they can do that at lunch. 15 ACTING CHAIRMAN FROINES: Stan -- 16 DR. GLANTZ: They keep saying they're smart. 17 ACTING CHAIRMAN FROINES: Stan and Gary and Paul, 18 I want to emphasize the value of that is that it is -- it's 19 not entirely independent, but it is a different way of 20 looking at the risk assessment and to the degree that 21 there's concern about the reliance on Garshick, this is 22 another piece of evidence that we can use as part of looking 23 at this overall picture, and I think it's extremely 24 valuable. 25 DR. GLANTZ: Maybe they can do it over lunch. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 82 1 They have a laptop computer. 2 ACTING CHAIRMAN FROINES: We don't have to worry 3 about getting the exact numbers out before we make 4 determinations. We all understand what Paul is talking 5 about. But it's the idea, I think. 6 DR. GLANTZ: Yeah. I think it's a good idea. 7 DR. BLANC: Because I do think that having a level 8 of 1.3 times 10 to the minus 2, which is so low, or so high, 9 depending on the language you want to use, it undermines the 10 utility of it. 11 So rather than doing something -- because we all 12 know that the exposure over all of those occupations was not 13 as low as five micrograms. 14 ACTING CHAIRMAN FROINES: The five is a bad 15 number. As we saw in Allan Smith's where he is up around 16 80, 60 to 80, that makes -- that's a more realistic number. 17 DR. FRIEDMAN: I think that, just to emphasize 18 what was said, that all these studies are estimates that are 19 listed in bold are all derived from the Garshick data, 20 either cohort or case control, and there's so much 21 contention about that, that it would be nice to have 22 something else that you did in bold too as another good 23 estimate. 24 ACTING CHAIRMAN FROINES: Well, that's also, Gary, 25 why I wanted to -- and we spent the morning getting the two PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 83 1 papers from NIOSH where two new risk assessments studies, 2 one on truckers has been done, so it gives us a new data set 3 entirely to look at. 4 And, again, the numbers are all turning out to be 5 pretty much the same, but it's nice to have different 6 sources of information to help confirm. 7 DR. BLANC: As an occupational health physician, I 8 do have to say that the video people have now gone beyond 9 the time that you promised them. 10 ACTING CHAIRMAN FROINES: Well, I was actually 11 trying to squeeze -- 12 DR. FUCALORO: Don't talk squeeze. 13 ACTING CHAIRMAN FROINES: I was hoping to get 14 through to 11:30 and breaking for lunch. You guys think you 15 can make that? 16 DR. BLANC: Can you go to 11:30 and break for 17 lunch? 18 ACTING CHAIRMAN FROINES: I knew what I was doing, 19 but I knew I was on tender ground here. 20 DR. BYUS: I'll be glad to run the camera. 21 ACTING CHAIRMAN FROINES: George, you want to try 22 to finish off in ten minutes? 23 DR. ALEXEEFF: I'm done with my presentation. 24 ACTING CHAIRMAN FROINES: Okay. I have a question 25 then for the panel. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 84 1 DR. ALEXEEFF: Unless you wanted -- we haven't 2 discussed comments. 3 ACTING CHAIRMAN FROINES: No, I think that we're 4 at a place now where we have to make a decision, and I would 5 argue that after lunch we go to the findings, which is going 6 to get us into the substance of the panel can take up a lot 7 of these issues, and maybe we won't take up the comments or 8 that we do take up the comments. My only concern about 9 taking up the comments is that it goes on for a very long 10 period of time, we're going to start having less time for 11 the panel's discussion. 12 And so however you want to do it. 13 DR. GLANTZ: Why don't we give Melanie ten minutes 14 to talk about the key comments, and then we go to 11:30 and 15 the key -- because I mean there was a lot of important stuff 16 in the comments. 17 ACTING CHAIRMAN FROINES: Can you do that? 18 Stan, let me act -- in the role of the chair, let 19 me -- how much time do you think you need on the comments? 20 DR. MARTY: Well, if you'd ask me that last night, 21 I would have said a half an hour, but I think I can buzz 22 through this in ten minutes. 23 ACTING CHAIRMAN FROINES: If you can do that and 24 then that means that we won't go to comments until later 25 with Genevieve. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 85 1 DR. GLANTZ: You're using up Melanie's time. 2 MS. SHIROMA: OEHHA will go first then and then 3 ARB with summary of comments and response and our proposed 4 revisions. For the ARB portion it's maybe five minutes' 5 worth of -- everyone has been mailed -- 6 ACTING CHAIRMAN FROINES: If we start at 1:00 7 o'clock we'll be finished with comments completely by 1:15, 8 1:20, 1:30? I really want to get us on to the substance of 9 this. 10 DR. GLANTZ: Let her do the comments. 11 ACTING CHAIRMAN FROINES: I understand. But I'm 12 not talking about Melanie. I'm talking about ARB right now. 13 MS. SHIROMA: Yes. Ours is very brief, short. 14 ACTING CHAIRMAN FROINES: So we will start at 1:00 15 on the dot, and we will be finished with comments at 1:15, 16 and then we'll start going around the table. 17 DR. MARTY: I think that the fastest way is for me 18 not be get up there with overheads and just to talk about 19 it, so that's what I'm going to do. 20 Essentially, we have grouped the comments by 21 underlying theme in order to talk about them today and to 22 stress the major substantive issues. 23 And I'd like to report that none of the issues 24 raised in the latest comment period are new. Some of the 25 details might be a little different, but the underlying PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 86 1 issues are the same that we have responded to in the past 2 Part C documents in May '97 and again in February '98, and 3 also in the responses to comments that we sent to you folks 4 last week. 5 There were comments concerning causality. The 6 commentators questioned how OEHHA could come to the 7 conclusion that epidemiological evidence supports a causal 8 link between exposure to diesel exhaust and the lung cancer. 9 And I think George went over that briefly earlier. 10 HEI made the comment that because of uncertainties 11 around whether there's a dose response can be estimated, the 12 extent of bioavailability in the small size of relative 13 risks, that they could not come -- that it made it difficult 14 for them to come to that conclusion. 15 And OEHHA has assessed causal inference using 16 standard criteria. The consistency of the findings is 17 there. The great majority of the epi studies find an 18 association. 19 The small magnitude of risks is offset by the 20 number and the diversity of occupations for which those 21 relative risks were found, and the consistency of the 22 findings from study to study. 23 We did analyze whether the possibility that the 24 findings could be due to bias or to chance, and our analyses 25 found that it is not likely to account for the effect. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 87 1 There is modest evidence of exposure response 2 based on the duration of exposure. 3 The temporality of the associations is such that 4 there's sufficient time elapsed between the start of 5 exposure and lung cancer in most studies. 6 And lastly there is biological plausibility. 7 There are mutagens and known human carcinogens and 8 respiratory tract carcinogens in diesel exhaust and diesel 9 exhaust does cause lung cancer in animal models. 10 And finally the HEI themselves report in their own 11 diesel exhaust document that the studies they reviewed 12 suggests an exposure to diesel exhaust in a variety of 13 occupational circumstances is associated with small to 14 moderate relative increases in lung cancer occurrence and/or 15 mortality. 16 These elevations do not appear to be fully 17 explicable by compounding due to cigarette smoking or other 18 sources of bias. Therefore, at present, exposure to diesel 19 exhaust provides the most reasonable explanation for these 20 elevations. 21 We had comments on causality, but I don't think 22 it's worth going over them at this point. 23 The other issue that was raised by several 24 commentators again hits on the bioavailability of the 25 genotoxins present on a particle phase. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 88 1 And their main points were that only extracts of 2 diesel exhaust particles are mutagenic, that the DNA adduct 3 data are not conclusive and therefore do not support 4 bioavailability, and that no enzyme induction was seen in 5 the chronic studies, and no immunological responses were 6 seen in animals, indicating a lack of bioavailability. 7 And our response to that is as was mentioned 8 previously, that while it is true that many of the studies 9 used diesel extract, diesel exhaust extract, and those were 10 positive mutagenicity studies, whole diesel exhaust also 11 induced mutation and four strains of salmonella and diesel 12 exhaust particles suspended in simulated physiologic fluids 13 were mutagenic in salmonella and also in mammalian cell 14 assays. 15 And I'd like to point out that the bioavailability 16 argument does not apply to the vapor phase genotoxins that 17 are present, which include low molecular weight PAHs and 18 nitro-PAHs, 1,3-butadiene, formaldehyde and a host of 19 others. 20 We did talk briefly about the DNA adduct data. I 21 don't think I need to go over that again, but we believe 22 that although there is some noise in the data it does 23 support bioavailability. 24 In terms of the lack of enzyme induction, they're 25 referring to the cytochrome P4 50 monoxygenates drug PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 89 1 metabolizing enzyme system. It is true that it was not 2 noted to be induced in the long-term bioassays. However, 3 induction of AHH activity over baseline is not required for 4 PAH metabolism. 5 The levels of PAH experienced by the lung cells 6 may be insufficient to induce enzyme activity, but 7 sufficient to produce genotoxicity. 8 There is evidence that macrophages can activate 9 benzo(a)pyrene coated on diesel particles and release the 10 metabolites to the surrounding medium. 11 And there are many recent studies showing 12 immunological responses to diesel exhaust particles. 13 Issues were raised about the uncertainty in the 14 occupational exposure estimates. I think we've really 15 covered that. I think it's safe to say that we believe that 16 bounding of our exposure reconstruction in the document is 17 such that it's unlikely that any of the exposures were lower 18 than our lower estimates or higher than our highest 19 estimates. And I think we stand by that. 20 It also was brought up that the extrapolating 21 downwards from occupational exposures to ambient levels, and 22 that extrapolation really is not unduly large if you're 23 familiar with risk assessment in general. It's on the order 24 of 10 to hundredfold, depending on what measurements you're 25 talking about. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 90 1 And other identified TACs had extrapolations up to 2 10,000-fold. We don't think that's really an issue. 3 Commentators brought up the issue that we're 4 assuming a linear nonthreshold model and we could have been 5 using other models. 6 The reason we chose the linear nonthreshold model 7 is the presence of the many genotoxic compounds in the 8 theory that the linear nonthreshold model is appropriate for 9 genotoxic mechanism of carcinogenicity. 10 There is not an evidence for a threshold effect in 11 humans. And particle overload is not evident in the workers 12 and we don't think it's an issue in terms of modeling the 13 dose response from epidemiological data. 14 We got some comments that Dr. Crump keeps getting 15 negative dose response curves. 16 There's a couple of reasons we think that is the 17 case. 18 One is that Dr. Crump treats clerks and signalmen 19 as if they were exposed to diesel exhaust, and we do not, 20 per the report in the Garshick study, which indicated that 21 those individuals were looked upon as unexposed to diesel 22 exhaust. 23 So I think that that is a big reason why we get 24 different analyses, different results of our analyses than 25 Dr. Crump. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 91 1 In addition, there is some collinearity problems 2 using cumulative exposure and counter year variables in the 3 same regression, doesn't provide reliable estimates of the 4 slopes because cumulative exposure is nearly proportional to 5 calendar year once you exclude the clerks and signalmen, 6 which was done in Dr. Crump's analyses. 7 Dr. Crump also pointed out that in our latest 8 attempts to account for exposure prior to 1959, which gets 9 back to the ramp and roof models, assumes that all workers 10 had that additional exposure prior to 1959. 11 And he also points out an error which resulted in 12 gaps in exposure in our program. 13 It is true that we assume that all those 14 individuals had exposure prior to 1959, but the correction 15 we realize was not going to be a perfect correction. We 16 just wanted to indicate that these exposures occurred and to 17 adjust the slope estimates to account for those additional 18 exposures. 19 We also corrected the error pointed out and reran 20 the model and this resulted in a small increase in the unit 21 risk estimate. 22 There's a few other issues raised on the modeling, 23 but I don't think it's worth going over them right now. 24 I did want to note that Dr. Kyle Steenland from 25 NIOSH forwarded as a comment an abstract of a manuscript PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 92 1 that he is publishing, and we just heard a little bit about 2 that, and he has an estimate that is on the order of 8 times 3 10 to the minus 4, right into the 10 to the minus 3 range as 4 a unit risk. 5 ACTING CHAIRMAN FROINES: Stayner is mining, and 6 Steenland is truckers. 7 DR. MARTY: Right. Dr. Duncan Thomas also was 8 communicating with Stan Dawson and sent a number of 9 comments, and Dr. Thomas presented at the March 11th SRP 10 meeting. He sent a number of comments supporting the 11 conclusion that lung cancer effects of diesel exhaust -- or 12 that lung cancer and diesel exhaust relationship is causal. 13 He gave us lots of positive comments, which I 14 probably should go through, but calls our meta-analysis 15 outstanding. 16 And he also was happy that we started -- we used 17 the Garshick case control and welcomed the reanalysis of the 18 Garshick cohort data. 19 He did express difficulty that the multistage 20 model where the last stage is considered to be the active 21 stage is biologically implausible, but when we run the 22 model, the model itself suggests that the final stage is 23 acted upon by diesel exhaust. 24 And in a preliminary analysis the fit of the model 25 with first stages dependent on diesel exhaust exposure is PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 93 1 much more poorer than the fit of the model with the final 2 stage being acted upon by diesel exhaust. 3 And then I should probably finally mention that 4 the California Trucking Association commented that OEHHA 5 missed an Australian study, which would disprove our 6 association between within diesel exhaust exposure and lung 7 cancer risk. That's pointed out in a number of studies in 8 our document. 9 And OEHHA's reviewed that study now as a technical 10 report from the Australian government. 11 The study is conventional cohort investigation 12 intended to examine all causes of mortality. It is not 13 specifically a study of lung cancer or of diesel exhaust. 14 And there were actually a number of problems, 15 technical problems, with the study, which was designed to be 16 a preliminary study anyhow. 17 There was not a minimum period of employment for 18 the coal miners to be in the cohort. They mixed coal miners 19 from underground mines and above-ground mines. They had 20 difficulties tracking the miners' work experience. 21 Most importantly the average age of the cohort was 22 between 40 and 50 years old, which is really not old enough 23 to be examining these individuals for incidence of lung 24 cancer. 25 And 30 percent of the cohort had been in the PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 94 1 industry less than ten years, so we didn't have enough 2 exposure time lapsing. 3 And also the report included deaths in the first 4 ten years of the cohort experience, which just adds noise to 5 the cancer analysis. 6 And finally the SIR for lung cancer for the entire 7 cohort, while appearing to be lower than the general 8 population, was actually not statistically significant. 9 Does anyone want to discuss individual points or 10 want me to touch on other things that you've read in our 11 response to comments? 12 DR. BLANC: I just want to say in terms of the 13 coal mining study, particularly such a hubbub was made about 14 it, I found it verging on the absurd that you even had to 15 respond to that. It was not germane and it was not 16 appropriate for analysis of any kind of cancer risk, let 17 alone diesel-related lung cancer risk. 18 So I think you're completely on safe ground by 19 disposing of that in short order. 20 And in fact the summary document upon which that 21 published paper was based, itself acknowledges that the 22 study cannot be used to address cancer risk because the 23 latency period is insufficient to evaluate cancer in that 24 cohort. 25 ACTING CHAIRMAN FROINES: Gary. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 95 1 DR. FRIEDMAN: I just want to add too that I was 2 very disturbed by some of the comments that said that your 3 group was biased, that you started out with a forgone 4 conclusion and just tried to prove it. 5 And I think that that's not true at all, and I 6 think those, that kind of comment is totally inappropriate. 7 I know your group has worked very hard to respond 8 to all the comments to really do an objective analysis, and 9 I think that people who make comments like that should 10 realize that they're just not appropriate. They're 11 ad homonym arguments which have no role in a scientific 12 discussion. 13 DR. GLANTZ: I just also, I thought you guys did a 14 very very fine job of responding to the comments. I mean, 15 there's a huge volume of them. They were very all -- they 16 were covering a wide variety of issues and I thought the 17 responses were really strong. 18 I have a couple of things I want to suggest, based 19 on the comments, but overall I think you just did an 20 exceptionally good job on it. 21 DR. MARTY: Thank you. 22 ACTING CHAIRMAN FROINES: I think when you look at 23 the US EPA document and you compare it to ours, it's really 24 very impressive, given that we're operating as a state 25 agency, in contrast to the federal government. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 96 1 And I can say, having been the longest term member 2 of the panel, that this is in fact the best document that 3 I've ever seen from OEHHA and ARB. It's really quite an 4 extraordinary document, I think. 5 And then with that, we'll break, because in the 6 afternoon it gets -- we start to go at the document a little 7 harder. Get the good news first. 8 We're going to start at 1:00, folks, because I 9 want to get everybody's energy going so we can get through 10 here today. 11 (Thereupon the lunch recess was taken.) 12 13 14 15 16 17 18 19 20 21 22 23 24 25 PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 97 1 A F T E R N O O N S E S S I O N 2 ACTING CHAIRMAN FROINES: I'm calling the meeting 3 to order. 4 The tension level in this room is much too low. 5 We expected about 500 truckers here. That didn't 6 materialize, and now everybody is so relaxed we can't move 7 anything forward. 8 So for better or for worse, whatever way we're 9 headed, let's move it along. 10 That requires Stan Glantz taking a seat. 11 And Genevieve and her people up here. 12 Tony is going to start with the findings. 13 Come on, Paul. We give you $100, we expect every 14 minute of your time. 15 What we want to do is to integrate comments on 16 Part A and Part B as we go through the findings. So you 17 guys are going to have to be creative, nonlinear, of course. 18 We're about to pass around the most recent NIOSH 19 information on risk assessment, which you won't have had a 20 chance to read, but that is literally hot off the presses. 21 And it has the advantage of being miners and truck 22 drivers, so it's not same old, same old. 23 DR. GLANTZ: We were discussing the origins of why 24 Hanspeter thought RR meant railroad. 25 DR. BLANC: That's because Stan is often trying to PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 98 1 railroad people with his epidemiologic -- 2 DR. GLANTZ: No, no. 3 ACTING CHAIRMAN FROINES: So we're ready to go. 4 Tony, could you take us through each section of 5 the first half of this? 6 DR. GLANTZ: Wasn't Genevieve going to talk about 7 their response to comments first? 8 ACTING CHAIRMAN FROINES: Who? 9 DR. GLANTZ: Genevieve. 10 ACTING CHAIRMAN FROINES: They will, but we're 11 going to move this so we can finish this today. 12 DR. GLANTZ: I'm fine. 13 ACTING CHAIRMAN FROINES: And we have had the 14 comments to read and Genevieve and Melanie know that as we 15 move forward here, where there are comments that are germane 16 to the findings, they will bring them in. 17 If there's new science, then somebody needs to 18 tell us about that, but I've been listening to this stuff 19 for nine years now, and I'm not hearing a lot of new 20 science. 21 DR. GLANTZ: Okay. 22 ACTING CHAIRMAN FROINES: Lot of mathematicians, 23 but that's about it. 24 DR. GLANTZ: Well, let's go. 25 DR. FUCALORO: Okay. I'm new to this, and was PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 99 1 called -- pressed into service because Jim Seiber had to be 2 out of the country, legitimate reasons, as far as I know. 3 And I have to report on Part 1 or Part A. 4 I'm just going to read something that Jim 5 suggested, some suggested language to be added to our 6 findings to see whether or not you agree with it. 7 After that I guess we can throw it open to the 8 discussion to respond to this. 9 ACTING CHAIRMAN FROINES: Usually we go around the 10 room and get comments. 11 We're now in the Part A findings, everybody, so 12 we're going to go around the room and get comments on the 13 Part A findings. 14 DR. FUCALORO: People can respond to this or make 15 any other statements they wish to make regarding Part A. 16 Let me read what Jim has written. 17 He said, although there is evidence that diesel 18 exhaust is carcinogenic, particulate matter concentrations 19 in California's estimated total population, air exposure has 20 decreased significantly from 2.1 plus or minus .8, he has 21 grams here, but micrograms per meter cubed in 1990, to 1.5 22 in 1995, and estimated values of 1.2 for 2000 and 1.1 for 23 2010. 24 Also very recent ARB-sponsored studies by UC 25 Riverside and UC Davis scientists show significant PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 100 1 reductions in concentrations of some carcinogenic components 2 and a reduction of specific mutagenic activity in exhaust 3 from modern diesel engine running on either reformulated or 4 low aromatic fuels of the types introduced in California in 5 1993. 6 Thus the trend in reducing particulate matter and 7 carcinogenic components in diesel exhaust emitted in 8 California is positive. 9 SRP recognizes the improvements made to date and 10 encourages further studies aimed at documenting and reducing 11 the toxic potential of diesel exhaust as emitted to 12 California's air environment. 13 I would say that that's not clear from what I 14 heard today that the carcinogenic activity of diesel exhaust 15 has been reduced, but it might have been reduced in these 16 new fuel formulations, and so the last sentence still 17 obtains, it seems to me, encouraging further studies aimed 18 at documenting and reducing the toxic potential of diesel 19 exhaust as emitted to California's air environment. 20 So with that, I would go around the table and see 21 what people think. 22 ACTING CHAIRMAN FROINES: You've made a 23 presentation. Do you want to respond to that? 24 MS. SHIROMA: Yes. Just to help direct the 25 discussion, I think that we have touched on Dr. Seiber's PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 101 1 points in your number five, also number nine, and number 10. 2 Now, in light of his comments, you may wish to add 3 more specificity, but I think the three topic areas are 4 covered, the estimated ambient total exposure, the 5 acknowledgement that the current regulations will reduce, 6 are anticipated to reduce that total exposure, and then the 7 CE-CERT analysis. 8 DR. FUCALORO: Right. 9 Of course in No. 10 I would argue, and you can 10 tell me if you agree with this, with the removal of the 11 sentence which says the results indicates that diesel 12 exhaust from the new fuel tested contained at the same 13 relative portions of toxic air contaminants as the old fuel. 14 I don't think that's quite accurate. I don't 15 think it changes any of our conclusions regarding diesel 16 exhaust as a toxic air contaminant. 17 I'm just not sure from the data, unless you can 18 convince me otherwise, that that's true. 19 MS. SHIROMA: And we are focusing on the toxic air 20 contaminant subset of the mix, but we could suggest that you 21 consider that the exhaust for the new and the old contain 22 the same constituents. 23 DR. FUCALORO: I think that's fair to say. 24 MS. SHIROMA: Okay. 25 DR. FUCALORO: I think that's fair to say, they PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 102 1 do. 2 MS. SHIROMA: Contain the same toxic air 3 substances as the old fuel. Take out the phrase relative 4 portions of? 5 DR. FUCALORO: Right. 6 MS. SHIROMA: So the sentence would read the 7 results indicate that the diesel exhaust for the new fuel 8 tested contain the same toxic air substances as the old 9 fuel. 10 DR. FUCALORO: Yes. 11 And I think in some ways that's accurate, but in 12 union with the next sentence, maybe you need some other 13 sentence in there which says, or something added to that 14 sentence, although, perhaps, perhaps at different 15 concentrations. So then that makes sense at the next 16 sentence which says further research will be helpful to 17 quantify the amounts of specific compounds emitted for a 18 variety of engine technologies, operating cycles and fuel, 19 to better characterize any differences between old and new. 20 MS. SHIROMA: So then we will add in -- and I 21 think that's -- 22 DR. KENNEDY: I don't mean to talk out of turn, 23 but are not the differences in new fuel more complex simply 24 than their carbon components? We're talking particle size, 25 which is really an unknown. We've got some balancing PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 103 1 forces. 2 I think that to make a summary statement that 3 reflects only these components is really not doing justice 4 to the changes, although I certainly would agree that we are 5 all in favor of continued investigation into what these 6 differences mean in terms of our safety. 7 DR. GLANTZ: I actually was going to suggest we 8 just delete No. 10. I think especially with the changes 9 that we're making now, I don't see what it really adds to 10 the findings. Everyone is always in favor of more research 11 and better fuel and all that. I mean -- 12 DR. FUCALORO: Well, I think in this case the 13 reason for putting it in, this is I'm speaking for Jim on 14 this, I think I agree with this, is that the composition of 15 diesel exhaust probably does change, not only the amount, 16 but the composition does change. It's different than, say, 17 benzene, which is one compound, but this is a mix of 18 compounds, a heterogeneous mix in terms of phases, that we 19 have to be very careful to note that the change may be good 20 and may be bad, and we have to -- and continuing research 21 would ensure that study continue. 22 DR. GLANTZ: Okay. 23 ACTING CHAIRMAN FROINES: You have a sentence that 24 you two can agree that will be in there? 25 MS. SHIROMA: I think we're very close. I was PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 104 1 going to suggest that perhaps a sentence that we're 2 suggesting on ES-11, the executive summary on page 11, to 3 add in the CE-CERT. We have a sentence saying -- it's 4 labeled as E-11 in the revisions to the February 23rd 5 report, and Peter just handed that around. 6 DR. FUCALORO: Read it. 7 MS. SHIROMA: A comparison of the milligram to 8 milligram per cubic meter emission profiles using the three 9 different fuels showed the presence of the same toxic 10 substances in a similar distribution of toxic substances, 11 but with a few substances showing much different emission 12 rates. 13 It then goes on to mention that in addition, 14 higher mutagenic activity was observed in both the particle 15 and vapor phase. 16 ACTING CHAIRMAN FROINES: That would be enough, I 17 think. Let's not -- these are findings and we're going -- 18 we're not going to take the executive summary and make it 19 into findings. These have to be simpler. So I would accept 20 a sentence, but -- 21 DR. BLANC: Let me suggest a phrase reflecting 22 what everyone has said. 23 The sentence would now read in point 10, the 24 results indicate that diesel exhaust from the new fuel 25 contains the same toxic air contaminants as the old fuel, PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 105 1 although there are concentrations and other components may 2 differ. Period. Further research, blah-blah-blah. 3 ACTING CHAIRMAN FROINES: I want to have further 4 research in there. 5 DR. FUCALORO: I do too. 6 DR. BLANC: Would that phrase be -- 7 ACTING CHAIRMAN FROINES: That's fine. 8 DR. FUCALORO: We can't call Jim Seiber, but I 9 think that reflects his -- 10 ACTING CHAIRMAN FROINES: If he gets a trip to the 11 Netherlands, he doesn't -- we don't have to check with him. 12 He made the trip after this thing was scheduled. 13 Give it to somebody who can be more responsible 14 than me. 15 That was good, Paul. 16 MS. SHIROMA: That will do it. 17 DR. FUCALORO: That works. 18 MS. SHIROMA: That works. 19 ACTING CHAIRMAN FROINES: I don't think -- I would 20 oppose putting in this mutagenic activity in. One, it 21 wasn't statistically significant and, two, it was change of 22 a half, and if you're a mutagenesis person going for a 23 change of a half doesn't really mean very much. 24 DR. GLANTZ: Could I just as a point of 25 information, are the findings, the draft findings you handed PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 106 1 out today, the same as the ones that were faxed around 2 yesterday? 3 MS. SHIROMA: Yes. 4 ACTING CHAIRMAN FROINES: This is just a working 5 document. 6 DR. GLANTZ: I just want to make sure, because I 7 read those and didn't read this. 8 DR. FUCALORO: I guess with that issue resolved, 9 as near as I can tell, it seems to, we can go around the 10 room now and gather the comments from various panel members 11 on Part A. 12 So I would ask Craig to -- 13 DR. BYUS: I have no comment. I agree with these 14 changes. I think it's perfectly fine. 15 ACTING CHAIRMAN FROINES: You're on 1 through 10. 16 DR. FUCALORO: 1 through 10, which is Part A. 17 ACTING CHAIRMAN FROINES: Check your notes and see 18 what you have. 19 DR. BYUS: I like the findings, virtually all of 20 them. 21 DR. FUCALORO: 1 through 10. 22 DR. BLANC: I have a question. 23 Vis-a-vis comments that were made, why did 24 somebody make a big deal about whether we said it was gases 25 and fine particles, as opposed to saying gases and vapors PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 107 1 and fine particles? Maybe our lawyer would say why that -- 2 that was lost on me as to what the -- it seemed to be a big 3 deal to somebody, and I couldn't figure out exactly why. 4 Do you remember that comment? 5 ACTING CHAIRMAN FROINES: When I see comments like 6 that I tend to go by them pretty fast, because I think 7 they're -- 8 DR. BLANC: I thought it had some legal 9 implication as well. 10 DR. FUCALORO: There is a scientific distinction. 11 DR. BLANC: That I know. 12 MR. KRIEGER: Dr. Blanc, I'd like to try to 13 address that. 14 Legal issue, I don't think that's the problem. 15 I think it was quoted in one part of our text as 16 being gases, vapors, particles, and another part of our text 17 it was quoted as gases and particles. 18 Diesel exhaust is a mixture of gases and 19 particles. The particles there's phases, you have a solid 20 phase and you have a vapor phase, so the confusion over the 21 terminology is what spurred that comment. 22 DR. BLANC: I only brought that up in terms of the 23 very first paragraph. It was a nonissue, it didn't matter 24 to me. 25 DR. FUCALORO: Now, Craig, you're completed? PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 108 1 DR. BYUS: I'm fine. 2 DR. FUCALORO: Paul, do you have any other 3 comments regarding the first ten conclusions? 4 DR. BLANC: Well, I wonder why John hasn't said 5 anything here. I guess you say it later about the 6 nitro-PAHs. So it's in the second -- it's in point 2, but 7 it's not in point 1, except PAH derivatives includes the 8 nitro-PAHs, I assume. 9 John, do you see what I'm talking about? 10 ACTING CHAIRMAN FROINES: Under 2? 11 DR. BLANC: Under 2 you specifically mention PAH 12 derivatives such as nitro-PAHs, but in paragraph one you 13 just say PAHs derivatives. 14 ACTING CHAIRMAN FROINES: No. Because paragraph 15 one is intending to focus on gases. 16 Paragraph two is intended to focus on 17 particle-bound chemicals. 18 There was a clear distinction made there. 19 You notice that in paragraph one we're talking 20 about products of incomplete combustion, gases, fractions, 21 includes all those, and the PAHs that we're talking about 22 there are things like naphthalene that are basically vapors, 23 in a vapor phase or gaseous phase. 24 Then you go down to two and you're talking about 25 the particle bound organics. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 109 1 MS. SHIROMA: Dr. Froines, maybe some of the 2 confusion is maybe this is just a typo and you paste and 3 click and so forth. Last sentence on No. 1 says some of the 4 gaseous components are and it includes arsenic and nickel. 5 And perhaps that's where some of the confusion is. 6 Perhaps that was meant to be moved. 7 ACTING CHAIRMAN FROINES: Well -- 8 DR. BLANC: Yeah. 9 ACTING CHAIRMAN FROINES: I had wanted to put in 10 the list of carcinogens identified, and that would have been 11 under three, and that didn't get in. It was on a slide here 12 today, but it never made the text, and I wanted it to be 13 spelled out. So I would just as soon take out that last 14 sentence of one, but I wanted it included under three. 15 MS. SHIROMA: And it would be more generic. Some 16 of the components -- 17 DR. BLANC: Get rid of the word gaseous then, is 18 what she's saying. So then it should read some of the 19 components of diesel exhaust, such as benzene, formaldehyde, 20 1,3-butadiene, arsenic and nickel are suspected or known to 21 cause cancer in humans, and that entire phrase then should 22 be moved to be the last sentence in point No. 3. 23 ACTING CHAIRMAN FROINES: Yeah. The only thing I 24 didn't like about this was -- it's okay. 25 DR. BLANC: Would that be acceptable? PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 110 1 ACTING CHAIRMAN FROINES: I would add chromium in 2 there. Add chromium in. But there are other -- 3 DR. BLANC: Well, you said some. 4 ACTING CHAIRMAN FROINES: Here's my point. This 5 is about the gaseous phase and some of the constituency -- 6 DR. BLANC: But clearly arsenic is not in a 7 gaseous form. 8 ACTING CHAIRMAN FROINES: Wait. Sure it is. If 9 nickel and arsenic are in a gaseous form, then chromium is 10 too. 11 DR. BLANC: Not as a fume? 12 ACTING CHAIRMAN FROINES: That's part of the 13 problem with this. 14 My problem was that I wasn't so sure we should 15 have the metals in here as gases. 16 DR. BLANC: Wouldn't that solve the problem if you 17 get rid of the word gases, and just say some of the 18 components? 19 ACTING CHAIRMAN FROINES: That's right. It saves 20 that. 21 But the point is I would rather have a section 22 under three where we actually list the carcinogens found in 23 diesel exhaust. And that wasn't done when I asked for it to 24 be changed. 25 So we list a few compounds here that in essence PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 111 1 referred to the gaseous aspect of it. 2 DR. BLANC: Well, let me ask you then, if you were 3 going to add other things that you felt were nongaseous, so 4 that we avoid the argument of arsenic and nickel, you would 5 include there PAHs and nitro-PAHs, or what else, what would 6 be missing? 7 ACTING CHAIRMAN FROINES: No. Because those 8 aren't -- 9 DR. BLANC: What would be missing from there, 10 assuming that we added chromium? 11 ACTING CHAIRMAN FROINES: You see what you've got, 12 we've created an apples and oranges problem here. We start 13 out talking about gases. 14 DR. BLANC: Well, I think it's confusing to talk 15 about those perhaps, then. 16 I mean is it that important to you that we talk 17 about those detailed gases. Your real point is that they're 18 carcinogens. So then doesn't it make more sense -- 19 ACTING CHAIRMAN FROINES: I would take out -- I 20 think we should just take out that sentence and have the 21 carcinogens listed under three. 22 DR. BLANC: Yeah, that's fine. 23 ACTING CHAIRMAN FROINES: Then it's in its 24 proper -- 25 DR. BLANC: That's what I am suggesting, PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 112 1 essentially. 2 ACTING CHAIRMAN FROINES: So we take out the last 3 sentence of one, and add a list of carcinogens that are 4 under three. 5 DR. FUCALORO: And I'm given to understand that 6 arsenic and nickel are probably organometallic type -- 7 ACTING CHAIRMAN FROINES: No, no. There's -- 8 DR. FUCALORO: I'm wrong about that? Nickel is in 9 what form just -- 10 ACTING CHAIRMAN FROINES: It's a fume. It's a 11 fume. And that's why it was incorrect actually to list it 12 as a gas, because you just have to decide what you think is 13 the relationship between a gas and a fume. 14 DR. FUCALORO: I see. 15 DR. GLANTZ: Are you saying that what we would be 16 doing then is like in No. 3 saying there are many 17 carcinogens in diesel exhaust, and then list the ones that 18 are listed in the report? 19 ACTING CHAIRMAN FROINES: Yeah. Irrespective of 20 their gases or particle base. 21 DR. FRIEDMAN: I would suggest, though, that when 22 you do that, since that statement in No. 3 says possible, 23 probable, et cetera, that you distinguish, because someone 24 might conclude that 16 of the 17 are just possible. So I 25 think that you should set a definite, the probable and PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 113 1 possible each listed separately. 2 ACTING CHAIRMAN FROINES: Right. 3 DR. BLANC: One other thing that would make it 4 clearer to the reader, because this was something that 5 confused me, I understand it now, but you've explained your 6 intent, would be actually since you want one section to be 7 about gases and the next one to be about particulates, 8 that's the intent, right? It would actually be clearer that 9 that's what you were doing if that's what we were doing if 10 point No. 1 was one sentence only, which was diesel exhaust 11 as a complex mixture of gases and fine particulates emitted 12 by diesel fuel internal combustion engine. And point two 13 would start the gases fraction is composed of, and then 14 everything else would be one number higher. 15 That would make it clearer, because the very first 16 sentence is what confused me, since that was a lead-in 17 sentence to talk about gases and fine particles. I never 18 would have realized it -- 19 ACTING CHAIRMAN FROINES: How about another 20 suggestion, because I don't quite agree. 21 How about if we have 1 A, B? 22 DR. GLANTZ: I think you should have two. 23 ACTING CHAIRMAN FROINES: I think 1, 2 and what is 24 now 2 will become 3? 25 DR. GLANTZ: Yes. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 114 1 DR. BLANC: Yeah. 2 DR. FUCALORO: I think so. Because it lays out 3 the -- one says they're both gaseous and particulate, and 4 two and three and give you the gases and -- 5 ACTING CHAIRMAN FROINES: That's fine. I don't 6 like one-sentence paragraphs. 7 DR. BLANC: I don't like bullet intros to 8 paragraphs that then don't talk about what the bullet intro 9 says. 10 DR. FUCALORO: Now that we handled these comments 11 on style, let's get back to the science. 12 DR. BLANC: John, I have one other, this is 13 actually just a very very minor thing. 14 In the former paragraph six, the very last 15 sentence, the sentence says it also excludes other routes of 16 exposure to diesel exhaust, such as ingestion and dermal 17 absorption, from deposition of diesel exhaust. 18 I almost wondered if there was a word missing 19 there or was that -- I wasn't sure what that comma was 20 supposed to make me -- 21 DR. FUCALORO: As an extra comma. 22 DR. BLANC: Does that comma really need to be 23 there? 24 The dermal -- well, my question is is both the 25 dirt got the diesel from deposition and the dermal PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 115 1 absorption is from deposition, right? So the deposition 2 refers to both of those things? 3 DR. KENNEDY: That sentence excludes other routes 4 of exposure to diesel exhaust from deposition to diesel 5 exhaust. That's the -- 6 DR. GLANTZ: The deposition of diesel exhaust 7 should be deleted. 8 DR. FRIEDMAN: Change it to exposure to deposited 9 diesel exhaust, such as ingestion of dirt and dermal 10 absorption. 11 DR. BLANC: Yes. That would be clearer. 12 DR. GLANTZ: Can I say one other thing about that 13 one? 14 There were some stuff in the public comments about 15 the problems of water, of compounds from diesel getting into 16 water, and then being, you know, drank or drunk, or 17 whatever. 18 And you can correct my grammar, Paul. 19 I think it would be just worth just mentioning 20 that, that there's another of the things that we're 21 excluding is diesel exhaust that gets in through the water 22 supply. 23 There were two letters in the public comments, or 24 more than two, there was a bunch, talking about that. One 25 was from the Bay Area Water Control District, or something. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 116 1 You're looking very blank, John. 2 ACTING CHAIRMAN FROINES: No. I'm waiting for you 3 to make some recommendation. 4 DR. GLANTZ: I would just recommend, and you have 5 a list here where you're saying it also includes other 6 routes of exposure to diesel exhaust such as ingestion of 7 dirt, water and dermal absorption. 8 DR. FUCALORO: And I'd like to take the lead here, 9 because I think Gary had a sentence that I think can 10 incorporate your suggestion. So if you can repeat -- 11 DR. FRIEDMAN: I just suggested taking off from 12 deposition of diesel exhaust and putting in the word 13 deposited before diesel, before diesel exhaust. So I'm not 14 sure how that would quite encompass Stan's concern. 15 DR. BLANC: All you have to do is insert the word 16 water after dirt. Dirt, water, and dermal absorption. 17 DR. FUCALORO: Why can't you have deposition? 18 DR. KENNEDY: The really key question here is not 19 necessarily the source, but the route of exposure, which is 20 the sentence. So routes of exposure include ingestion and 21 dermal absorption, and that's it. And you can eat it, you 22 can drink it, you can roll in it, and sort of there. 23 Beating the horse. 24 ACTING CHAIRMAN FROINES: Peter, where are you 25 making -- PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 117 1 DR. KENNEDY: The same sentence, that excludes 2 other routes of exposure as -- meaning noninhalants, to 3 diesel exhaust, such as ingestion and dermal absorption. 4 Period. End of discussion, end of sentence. It implicitly 5 includes any form of ingestion. 6 DR. BLANC: Dirt or water. 7 MS. SHIROMA: Gentlemen, along those lines, 8 Melanie was reminding me that crop ingestion is also another 9 key example. These were meant to be examples, but 10 Dr. Kennedy -- 11 DR. GLANTZ: I like what Genevieve is suggesting. 12 ACTING CHAIRMAN FROINES: I'm still trying to get 13 it. 14 Such as ingestion of dirt? 15 DR. KENNEDY: Just ingestion. 16 DR. GLANTZ: Ingestion and dermal absorption, 17 period. 18 ACTING CHAIRMAN FROINES: Got it. 19 DR. KENNEDY: Source of the contamination is not 20 important. It's the route of it. It's the route of 21 application. 22 ACTING CHAIRMAN FROINES: Got it, Genevieve? 23 MS. SHIROMA: Got it. 24 DR. GLANTZ: The sentence would read it also 25 excludes other routes of exposure to diesel exhaust such as PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 118 1 ingestion and dermal absorption, period. 2 That's what you were suggesting; right? 3 ACTING CHAIRMAN FROINES: You done? 4 DR. GLANTZ: I think that's fine. 5 DR. FUCALORO: Is there any other comment on this 6 issue? 7 If there isn't, we get back to Dr. Blanc who -- 8 DR. BLANC: No. That's it. 9 DR. FUCALORO: You're finished with your comments? 10 MS. SHIROMA: Pardon me, Dr. Fucaloro. Sorry to 11 interrupt. 12 Just a protocol comment. Kirk has indicated for 13 members of the audience that there are extra copies of the 14 material that you're looking at now on the table. 15 And then also Kirk is reminding that the other SRP 16 members are now back from lunch and have been for some time, 17 just for the record, since we reconvened. 18 DR. FRIEDMAN: I have nothing to add on this part. 19 DR. FUCALORO: Good. 20 We'll go around to Dr. Glantz. 21 DR. GLANTZ: I'm happy now. 22 DR. FUCALORO: I'm sorry. I didn't hear you. 23 DR. GLANTZ: I have nothing more. 24 DR. FUCALORO: Nothing to add. 25 DR. WITSCHI: I was wondering, the first sentence, PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 119 1 you describe the diesel engines -- 2 DR. FUCALORO: I'm sorry. What you are looking 3 at? 4 DR. WITSCHI: No. 2. The first sentence, does it 5 still adequately describe new types of diesel engines? 6 DR. FUCALORO: That's a good question. 7 I guess, I certainly don't know the answer to that 8 and would call upon members of the ARB. 9 DR. WITSCHI: I recently talked to Joe Mauderly 10 and he told me, this isn't a quote, but when they did the 11 first diesel studies with the '81 engine they had, they had 12 to dilute the smoke to get about eight milligrams per cubic 13 meter. And they repeated the studies in '86 or '88 and the 14 new engine, and they just could use what came out of the 15 tailpipe for getting the same particle loads they had in the 16 previous study. And if he was going to use a modern today 17 engine, he would have to concentrate what they were coming 18 out of tailpipe. 19 So I'm really wondering with this statement that 20 release of particles at the rate of about 20 times greater 21 than from gasoline fueled vehicles if this is still true 22 with modern technology. 23 DR. FUCALORO: Go ahead. 24 MR. KRIEGER: Dr. Witschi, the 20 times greater 25 comes from at least the most recent study that we're aware PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 120 1 of which examines early 1990 engines, and that was from 2 actually the World Health Organization report. That 20 3 times calculation came from that. 4 In our report we mentioned, and like you said, 5 it's true, the older engines have greater amount of 6 particles than the gasoline, they just didn't catch up in 7 technology yet, but we mention it's a 50 to 80 times greater 8 in the report, but generally it's 20 times a good number 9 right now for the current technology. 10 DR. WITSCHI: But the greatest, they way this 11 reads, this is a one-dimensional statement in a 12 multidimensional world. 13 DR. FUCALORO: How would you suggest changing it 14 or would you suggest eliminating it? I mean, you're 15 obviously critical of the statement. Can we modify it? 16 DR. WITSCHI: Well, this is clearly something that 17 has changed over times, and probably is going to change over 18 times too. 19 And in this describing diesel exhaust, those 20 changes that have been accomplished and those changes which 21 are going to occur should be acknowledged. As I said, 22 otherwise it becomes a one-dimensional statement, which does 23 not reflect reality. 24 DR. BLANC: Well, I have a suggestion that I think 25 that would address that. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 121 1 Part of that is covered in the later points, but 2 in terms of making it clearer, because later points are made 3 about the changing technology and so forth, but I think the 4 addition of the following phrase at the end of the first 5 sentence would perhaps address your concern, such that it 6 would read now at the very end of the sentence, on an 7 equivalent fuel energy basis, based on technology currently 8 in use, period. 9 DR. WITSCHI: I'm not so sure about current. He 10 said 1992. We have 1998. 11 DR. BLANC: Based on technology in use, widely in 12 use as of 1992. 13 DR. WITSCHI: Well -- 14 DR. BLANC: I think -- 15 DR. WITSCHI: There is an additional problem 16 there, and this is not only the progress in engine 17 technology, but the other problem of not as many changes in 18 the fleet as we could expect from changing technology. 19 Because many of these old clunkers, which are emitting more, 20 are still around, actually too many of them. 21 DR. BLANC: You're saying for many, it's more than 22 20? 23 DR. WITSCHI: Yeah. 24 DR. BLANC: I think the number 20 reflects an 25 average of old technology and new technology. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 122 1 DR. WITSCHI: What it's bothering me is this first 2 sentence simply doesn't describe the situation. It's much 3 more complex, and which eventually is coming to judge health 4 effects have to consider to some extent. 5 MS. SHIROMA: May we offer some suggested 6 language? And then Dr. Witschi's comment. 7 Again, the suggestion is one of the main 8 characteristics of diesel exhaust is the release of 9 particles at a relative rate of 20 times or greater than 10 from gas fuel vehicles, depending on -- dependent on the age 11 and operating conditions of the vehicles, because that's 12 essentially what the WHO report indicated, that it could be 13 up to 80 times, depending on the age and operating 14 conditions of the older -- 15 DR. WITSCHI: I would agree with extrapolating 16 back up to 80 or whatever it is, but I'm not quite so sure 17 about the 20. 18 DR. FUCALORO: Do you want to avoid any specific 19 quantitative term or we can put in a hedge word, many 20 multiples of that from gasoline-powered vehicles. Would 21 that be better for you? 22 DR. WITSCHI: It might. I'm still not -- 23 DR. FUCALORO: In some ways it seems to me in 24 reading the remainder of that paragraph, that first sentence 25 isn't that important to mention gasoline-fueled vehicles. I PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 123 1 mean, except to mention that there's -- to indicate that 2 there's a large fraction of the exhaust is particulate 3 matter in diesel powered. 4 And then the second sentence the particles are 5 mainly aggregates of, and that's specific to diesel fuel. 6 So maybe that's the approach once you take that 7 it's recognized that a good portion of diesel exhaust is in 8 the form of particulate matter. 9 Then the particles are mainly aggregates, and so 10 on. 11 DR. FRIEDMAN: I think, though, that the 12 comparison with gasoline is worthwhile because people are 13 saying, there had been some comments, you know, why are you 14 picking on diesel exhaust, why don't you pick on all 15 exhaust. 16 So I find that some kind of comparison, whether 17 it's 20 times or something indicating a much larger rate of 18 particle formation -- 19 DR. FUCALORO: But his point, of course, is that 20 the absolute quantitative amount is such a difficult thing 21 to nail down, because there are older vehicles, newer 22 vehicles, changes since 1990 something, whenever you had the 23 last measure. So one could then also say that it is a -- 24 that the particulate matter is a large portion, much higher 25 than in gasoline-powered vehicles. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 124 1 ACTING CHAIRMAN FROINES: Why don't you just 2 say -- excuse me. Why don't we just say which is the 3 release of particles greater than from gasoline-fueled 4 vehicles on an equivalent fuel basis? 5 DR. FRIEDMAN: Would it be fair to say 6 considerably greater? 7 DR. BLANC: I would actually say at least in order 8 of magnitude greater, because even -- you know, even if 9 you're not happy with 20, I think that they -- 10 DR. FUCALORO: At the minimum. 11 DR. BLANC: Ten is certainly giving you even more 12 of a fudge factor downward. So I would say that if we said 13 at least in order of magnitude it would put things in the 14 range that we're talking at a minimum. 15 ACTING CHAIRMAN FROINES: Let's do that. 16 DR. WITSCHI: The other thing is that might be a 17 bit off the wall, but the emphasis on particles puts 18 everything we think is bad about diesel, the particles, and 19 that's a fact I'm not convinced of. 20 DR. BLANC: I don't think that starting with 21 paragraph one gives that impression. 22 DR. WITSCHI: Okay. 23 DR. FUCALORO: It talks about both particles and 24 the vapor phase and this particular paragraph has to do with 25 the particulate matter. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 125 1 DR. BYUS: I think we do have to make some 2 comparison with the gasoline engine. Everyone accuses us of 3 picking on diesel. I mean, this is the reason. It's 4 explained in detail. 5 I would be in favor of using the word markedly 6 more, instead of just tenfold. I don't think you can put 7 any number. But I would say markedly more, and then leave 8 it at that. 9 I mean, you could say even that there has been a 10 number of attempts to improve the emissions of diesel 11 engines. Everybody knows this. If we want to put something 12 in the findings, because they have, I mean, later on they 13 mention it. But I would say just markedly more particles. 14 ACTING CHAIRMAN FROINES: I want to go back and -- 15 DR. FUCALORO: Can I get closure on this? 16 Do you think do you have the wording that 17 represents that? 18 MS. SHIROMA: Yes. One of the main 19 characteristics of diesel exhaust is the release of 20 particles at a markedly greater rate than from 21 gasoline-fueled vehicles -- 22 DR. FUCALORO: On an equivalent fuel basis. 23 MS. SHIROMA: On an equivalent fuel energy basis. 24 DR. FUCALORO: Does everyone find that acceptable? 25 ACTING CHAIRMAN FROINES: I thought it was -- is PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 126 1 the release or particles at least in order of magnitude 2 greater than from gasoline-fueled vehicles? 3 DR. FUCALORO: That was the previous suggestion by 4 Paul. But Craig has said -- wants to go to back to the less 5 quantitative statement and used the word markedly greater. 6 My own preference, I don't have a preference. I 7 think both are fine, as far as I can tell, but so I'm 8 willing to accept either one, but if any of you -- 9 DR. FRIEDMAN: Is there any concern that it could 10 be less than tenfold greater? 11 Hanspeter, is it -- 12 DR. WITSCHI: Yeah. According to what some people 13 telling me is that today's 1998 diesel engines approximate 14 internal combustion engines with regard to what's coming out 15 of the tailpipe. 16 DR. FRIEDMAN: Then I guess I would stick to 17 markedly. 18 DR. FUCALORO: Then I go with Craig. 19 DR. WITSCHI: It's something that really would 20 have to be checked into. 21 ACTING CHAIRMAN FROINES: I think we should draw 22 this to closure. 23 DR. FUCALORO: I think we have. 24 Do we all agree on Craig's wording, that is to say 25 markedly greater? Okay. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 127 1 ACTING CHAIRMAN FROINES: I want to go back to one 2 for a second, where we say volatile hydrocarbons, aldehydes, 3 et cetera. 4 I want to have it changed to be volatile organics 5 such as aromatics, butadiene, benzene, formaldehyde as 6 example, because volatile hydrocarbons is not a sufficient 7 descriptor of the gaseous compounds. 8 You can say, you can include hydrocarbons, but I 9 think we need to show that there are other volatile 10 hydrocarbons, aromatics, alkenes, such as volatile 11 hydrocarbons, alkenes, aromatics, aldehydes and low 12 molecular weight polycyclic or aromatic compounds. 13 DR. FUCALORO: Any comments on that suggestion? 14 If it's -- if not, if it's been recorded, we'll 15 move on. 16 ACTING CHAIRMAN FROINES: Peter, you done? 17 DR. WITSCHI: I'm done. 18 ACTING CHAIRMAN FROINES: Everything? 19 DR. FUCALORO: We have another Peter. 20 ACTING CHAIRMAN FROINES: One through ten. 21 DR. KENNEDY: I have one small change, since we're 22 talking levels of comfort. 23 On the last line, become trapped into is 24 grammatically incorrect. I would suggest trapped within the 25 small airways and alveoli of the lungs. Anatomically, small PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 128 1 airways is a better term. 2 DR. FUCALORO: I'll defer to your knowledge on 3 that. 4 ACTING CHAIRMAN FROINES: Go ahead. 5 DR. FUCALORO: Did you record that? 6 Any comment on that? 7 I come back to you, John, do you wish to make any 8 comment? 9 This is your construct, so I guess maybe you're 10 pleased with that. 11 Okay. Again, this is my first go-around at this 12 sort of thing. 13 Are my duties completed or do I need to -- 14 ACTING CHAIRMAN FROINES: You're done. 15 DR. FUCALORO: I'm done. Thank you. 16 ACTING CHAIRMAN FROINES: Thank you very much. 17 Okay. Now, we'll get down to the hopefully 18 easiest part of the discussion. We want to go over now the 19 health effects associated with diesel exhaust. 20 I am the lead, so I'll take the lead on going 21 through it. 22 I just want to say that as far as I was concerned, 23 the document dealt, as far as my reading, with both animal 24 and human acute effects of diesel. The document deals with 25 chronic, again animal and human effects of diesel. The PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 129 1 document deals with immunologic effects, animal and human. 2 It has some discussion of mortality of non-cancer effects. 3 It deals in animals and humans with respect to genotoxicity. 4 It addresses bioavailability, which is a very important 5 issue. 6 I should say that we're doing a lot of work now on 7 chromium where we're finding in fact that particles are not 8 bioavailable, and so in some cases with some substances you 9 have real significance with respect to carcinogenicity. 10 And finally, the document deals with lung cancer. 11 Now, I've left out some other categories, like 12 reproductive effects, developmental effects, bladder cancer, 13 because those the document concluded there was not 14 sufficient evidence, although it may have hints of evidence 15 to focus health effects discussion on those. 16 So that the ones, the list I just went through, 17 represent those effects, those health effects that the 18 document addresses that they consider significant within the 19 context of identifying diesel exhaust as a toxic air 20 contaminant. 21 So we have the obligation now to determine 22 whether, in terms of finding this as a toxic air 23 contaminant, whether or not the State has met the burden of 24 proof or the quality within the context of those subject 25 areas. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 130 1 So it seems to me that perhaps one of the first 2 things we can address within the context of the health 3 effects part of the findings is those areas where we -- 4 there is evidence for health effects. 5 And I'll go around the room and I'll start with 6 Craig Byus again and come back to finish with Tony. 7 DR. BYUS: Yeah. I have minimal comment on this 8 as well. I find after the last meeting I had all the issues 9 I had cleared up and I think it's written quite well in 10 terms of the in vitro and in vivo data. I'm very pleased 11 with it. 12 ACTING CHAIRMAN FROINES: We love those kinds of 13 comments. 14 DR. FUCALORO: The author loves those type of 15 comments. 16 DR. BLANC: One of the things that struck me 17 throughout those discussions in the focus on the 18 carcinogenic issues associated with diesel exhaust has been 19 the relative back burner that non-cancer risk has had to 20 take, and it's partly driven by the requirements for 21 quantitative attempts and quantitative risk assessment, I 22 realize, and how that kind of risk assessment gets even more 23 complicated dealing with non-cancer outcomes. 24 I believe that even absent any evidence of 25 carcinogenicity, which is overwhelmingly convincing for PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 131 1 this, that this would be a toxic air contaminant on the 2 basis of its non-cancer health-related effects. 3 I don't think we need to say that explicitly, but 4 what I would like to see, I think, in the current number, 5 14, which will I guess change to 15 as all the numbers get 6 inflated by one, is a statement which might say something 7 like it should be recognized that this reference exposure 8 level may need to be lowered further as quantitative data 9 emerge on the potential adverse non-cancer effects from 10 diesel exhaust in the future. 11 ACTING CHAIRMAN FROINES: Paul, can you say that 12 again slowly. It should be recognized that -- 13 DR. BLANC: It should be recognized that this REL 14 may need to be lowered further as quantitative data emerge 15 on potential adverse non-cancer effects from diesel exhaust. 16 Because I think this is an area -- 17 ACTING CHAIRMAN FROINES: To be lowered further? 18 DR. FUCALORO: I would get rid of the word 19 further, wouldn't you, Paul. 20 DR. BLANC: Lowered, okay, as quantitative data 21 emerge on potential adverse non-cancer effects from diesel 22 exhaust. 23 ACTING CHAIRMAN FROINES: So that would be added 24 to 14? 25 DR. BLANC: Yeah, the end of it. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 132 1 ACTING CHAIRMAN FROINES: I don't see anybody 2 standing up and protesting. 3 DR. BLANC: This is also just a question about are 4 we discussing all the rest of the points? 5 ACTING CHAIRMAN FROINES: Yes. 6 DR. BLANC: Or just the points related to -- 7 because there's some summary points at the end. 8 ACTING CHAIRMAN FROINES: Well, I think what we 9 should do is we should be going through the points that you 10 have in your head as things you want to address. As we get 11 all around and there are points that are not yet addressed 12 we should take that up then. 13 But you can only do what you can do, and others 14 will presumably raise other points and then we'll have to go 15 back and look at the document overall. 16 DR. FUCALORO: What Paul was just suggesting that 17 items 20 through 22 are a summary. 18 ACTING CHAIRMAN FROINES: We'll have to go back to 19 those. 20 DR. BLANC: Okay. 21 ACTING CHAIRMAN FROINES: So in a sense we're 22 trying to deal with everything in a sense leading up to 23 that. 24 DR. BLANC: Right. 25 ACTING CHAIRMAN FROINES: If everybody agrees with PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 133 1 everything that leads up to that, then that pretty much 2 makes those last points they follow presumably, but we'll 3 see. 4 DR. BLANC: Okay. 5 DR. FRIEDMAN: I thought that these were very well 6 done, but I have one suggestion for the item that's 7 currently numbered 16. 8 There's a sentence that seems to be trying to 9 combine two ideas and it sounds like a non sequitur. 10 OEHHA analyzed the lung cancer findings for 11 consistency and found that the association was unlikely to 12 be due to chance. 13 I think that should be, if I understand it 14 correctly, it should be restated that OEHHA found the lung 15 cancer findings to be consistent and found that the 16 association was unlikely to be due to chance. 17 There's two different things going on there. 18 ACTING CHAIRMAN FROINES: OEHHA found the lung 19 cancer findings -- 20 DR. FRIEDMAN: To be consistent. 21 ACTING CHAIRMAN FROINES: And found the 22 association was unlikely due to chance? 23 DR. FRIEDMAN: Right. 24 DR. FUCALORO: Making it a compound sentence. 25 DR. FRIEDMAN: There's two things. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 134 1 My only concern now with that change, and I don't 2 have a better suggestion at this point, is there's the 3 found, findings and findings. There's too many -- maybe you 4 can say concluded, OEHHA concluded that the findings were 5 consistent. 6 DR. FUCALORO: I find it to be fine. 7 DR. GLANTZ: Actually, though, these are really 8 our findings, not OEHHA's findings, so I would suggest that 9 we leave OEHHA out of it and just say the lung cancer 10 findings are consistent and unlikely to be due to chance. 11 DR. FRIEDMAN: That will be fine. 12 ACTING CHAIRMAN FROINES: Lung cancer findings are 13 consistent and the association -- 14 DR. GLANTZ: Is unlikely to be due to chance. 15 ACTING CHAIRMAN FROINES: Is unlikely to be due to 16 chance. 17 You have to remember that Stan is pretty good at 18 this kind of thing, for those of you who don't remember the 19 lead day. 20 DR. GLANTZ: Halloween. 21 DR. FRIEDMAN: That's all I have. 22 ACTING CHAIRMAN FROINES: Okay. Stan, we never 23 assume that you will have quite the succinctness that Gary 24 and Paul -- 25 DR. GLANTZ: I just have a couple of things. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 135 1 No. 16, I think the last sentence of No. 16 should 2 be moved to No. 15. 3 And then in No. 18 -- well, let me, just before I 4 comment on No. 18, I think that the -- 5 ACTING CHAIRMAN FROINES: You're saying that the 6 last sentence in 16 should -- 7 DR. KENNEDY: Is not a epidemiologic study. It's 8 animal information. 9 ACTING CHAIRMAN FROINES: Good. 10 DR. GLANTZ: Belongs with No. 15. 11 DR. KENNEDY: Can I expand on that just a moment? 12 Because I think there are a lot of conflicting 13 animal data, even though this is clearly positive, and is 14 there any responsibility to note that there are 15 species-specific differences or that any issue of 16 transference of mechanism needs to be considered? 17 It gets a little messy, but I think it is the 18 responsible thing to do. 19 ACTING CHAIRMAN FROINES: Peter, were you going to 20 say something about that? 21 DR. WITSCHI: No. Well, I really -- no, I don't 22 think so. 23 First of all, we have only three animal species 24 where this thing has really been tested, out of one -- which 25 one, the hamster, never gets lung cancer from any PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 136 1 inhalation. So that's the one thing. 2 DR. KENNEDY: Mice where this doesn't really 3 happen -- 4 DR. WITSCHI: In mice it does happen, yes, in 5 some, but the evidence is not all that good and all that 6 consistent. 7 ACTING CHAIRMAN FROINES: It would be interesting, 8 because I feel that the mouse issue is unresolved. I think 9 there are definitely positive studies, and it's very 10 dangerous to take a well-constructed animal study, 11 specifically with mice, and find positive results and then 12 draw a conclusion that there's no evidence in mice. 13 I think that if we went back and did similar 14 studies with mice it would end up being positive. But I'm 15 not arguing that. 16 So I think mice is one of the missing areas in 17 this whole toxicologic investigation, but we're stuck with 18 the data that we have, so we could say further animal 19 research is relevant, but nobody is going to want to do it. 20 So one could say something about -- you could say 21 although the mechanisms by which diesel exhaust induces lung 22 cancers in the rat are not certain, but there may be some 23 species specificity associated, but then we are making -- we 24 as a panel are making a decision about a mechanism and this 25 is a bit more neutral. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 137 1 I'm not sure the panel wants to make that -- 2 DR. WITSCHI: I'm not sure what you mean. 3 ACTING CHAIRMAN FROINES: What I'm saying is if we 4 say something, if we hint anything about overload or 5 Mikaylas Menton clearance processes or any of that, we're 6 actually entering into the discussion of the mechanism, and 7 it seems to me that we probably don't want to do that. 8 And if you're the person that's shaking your head 9 no, then I'm happy, because you're the most knowledgeable in 10 that respect. 11 DR. WITSCHI: Because if you're going down that 12 route, you're going to find out that mice are unique too, 13 the way they handle butadiene. 14 ACTING CHAIRMAN FROINES: I think Peter and I 15 agree on one thing in the world, and that is butadiene is an 16 important chemical. 17 DR. BLANC: Dr. Kennedy, I'm not sure where we are 18 at this point. There's been some back and forth. 19 Are you satisfied with just moving the sentence as 20 is? 21 DR. KENNEDY: I am -- 22 DR. BLANC: Do you still want to say something 23 additional? 24 DR. KENNEDY: I'm happiest with just moving it up. 25 And maybe the mechanism by which diesel exhaust PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 138 1 induces lung tumors is not certain. One could simply remove 2 that clause. 3 DR. WITSCHI: Could we just add results of 4 inhalation bioassays in the rat and with lesser certainty in 5 mice have demonstrated the carcinogenicity. 6 ACTING CHAIRMAN FROINES: Say it again, Peter. 7 DR. WITSCHI: Results of inhalation bioassays in 8 the rat and with lesser certainty in mice have demonstrated 9 the carcinogenicity of diesel exhaust in test animals. 10 DR. KENNEDY: I'm happy with that. 11 DR. FUCALORO: If you put in the phrase with test 12 animals. 13 ACTING CHAIRMAN FROINES: Read it to me again. 14 I'm sorry. 15 DR. WITSCHI: Result of inhalation bioassays in 16 the rat and with lesser certainty in mice have demonstrated 17 carcinogenic potential of diesel exhaust in animals. 18 ACTING CHAIRMAN FROINES: You want to keep the 19 sentence about mechanism in still? 20 DR. BLANC: No. He wanted to delete those. 21 DR. BYUS: Is everybody convinced then that 22 diesel, all -- I mean that the diesel exhaust 23 carcinogenicity in rats cannot be explained by the particles 24 alone? That's the question. 25 ACTING CHAIRMAN FROINES: Wait. Let me just deal PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 139 1 with the factual. 2 Peter, are you taking out -- 3 DR. WITSCHI: Take out the second sentence. 4 DR. BYUS: You see what I'm saying, I like the 5 idea of the uncertain mechanism in a sense what we're 6 saying, I mean my interpretation of that data was that much 7 of the carcinogenicity, I would say much, not at all, but 8 much of it in the animal data, the rat data, is explained by 9 particle overload and the particles themselves, not 10 necessarily. And so that eliminate diesel exhaust as being 11 positive, simply the particles at very very high doses. 12 ACTING CHAIRMAN FROINES: I don't think the 13 evidence -- 14 DR. BYUS: That's what I'm asking everybody. 15 ACTING CHAIRMAN FROINES: I think what happens 16 sometimes in science is that people want a hypothesis to 17 work out to be the correct hypothesis, so the research that 18 gets done gets emphasized in that area. 19 There's a lot of research on animals that hasn't 20 been done. So in a sense what Joe Mauderly, who is a very 21 fine scientist, has done, though, has focused his research, 22 thereby leaving a bunch of questions unanswered. 23 So the role of more semantic cell mutation, the 24 role of nitro-PAH carcinogenicity as is yet unresolved. It 25 may not be important. It may be important. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 140 1 I think it's important. 2 DR. BYUS: So do I. 3 ACTING CHAIRMAN FROINES: I think there are others 4 that do. 5 So I think what we have now is we have a body of 6 literature which is holding a place, but it doesn't mean 7 it's holding the answer. It's just holding the place. 8 And so I'm not ready to say, yes, because you've 9 got titanium dioxide and carbon and diesel and they all look 10 about the same, that therefore the answer that follows is 11 true. I don't agree with that. 12 And I think what we're going to see as we go 13 forward is that both mechanisms are going to be playing a 14 role. 15 DR. BYUS: I agree with you. 16 What I'm asking you is does the animal data in 17 rats demonstrate that diesel exhaust is a carcinogen? 18 That's what we're saying, does it demonstrate it? 19 And I'm not sure that it demonstrates it. 20 ACTING CHAIRMAN FROINES: I think two things. 21 One, I think there is one piece, one biological 22 issue that's important, and that is that diesel produces 23 cancers in mice, it appears, in rats and in humans. 24 Now, you can go through each one of those and find 25 reasons why any one of them are not true, but I think that PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 141 1 you have to take seriously the fact that you have three 2 species that have cancer from a similar exposure. 3 That, by itself, is important, I think, whatever 4 the single species arguments and all that. 5 But that doesn't -- just one more point. 6 So but put that aside. 7 All I'm saying is with respect to the rat it 8 appears that the mechanism of the carcinogenicity in the 9 lung of the rat could change depending upon the dose that 10 the rat receives. And that is the high dose may have a 11 mechanism different than what you might find at a low dose. 12 DR. WITSCHI: Address your concern about has it 13 been demonstrated, I mean if you look at carcinogenesis, and 14 particularly inhalation assays in general, the diesel is 15 really almost the only confounder. We have gotten almost 16 identical results in at least three or four or five 17 different labs. In all those labs they produced lumps and 18 to me it has unequivocally -- 19 DR. BYUS: But some of the particles, that's the 20 point. And this is the point, clearly. 21 So you're then you have to say is it the particles 22 or is it the diesel exhaust itself with the carcinogens. 23 You can't ignore that when you say demonstrate. 24 That's what I'm getting at. That why I'm trying to say is I 25 liked your attempt at qualifying that statement with the PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 142 1 mechanism. In a sense now we take that mechanism statement 2 out, we're -- I mean, I'm less comfortable with it in a 3 sense. 4 I agree with everything you say, but I just I 5 think you can't get away from that point. It could be the 6 particles themselves. The animal experiments, could it all 7 be explained by particles, that's -- I'm not sure that it 8 couldn't be, but certainly in rats it could be. 9 DR. WITSCHI: Well, you -- 10 DR. BYUS: The other animals I'm less sure. 11 DR. WITSCHI: If you listen carefully to Joe, he 12 never said that he doesn't believe diesel does the cancer, 13 probably one of those mechanisms Joe alluded to. 14 All he said really was this particular mechanism 15 or because it's a particular mechanisms which produced 16 apparently those lumps in rat, we should not use this for 17 the human situation. That's all he says. He never said 18 that he didn't believe diesel was not carcinogenic. 19 ACTING CHAIRMAN FROINES: In fact he does. He was 20 asked at a meeting I chaired and in fact he acknowledged 21 that it was a carcinogen. 22 So that then we also have the issue going back to 23 our favorite chemicals of things like benzene, formaldehyde, 24 acetaldehyde, butadiene, that there are things besides 25 particles that people breathe that do cause lung cancer, and PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 143 1 so it's entirely possible that when you're breathing all 2 these gaseous compounds that are carcinogens, they may be a 3 source of cancer that does not have anything to do with 4 overload. 5 DR. BYUS: I have no doubt. I have no doubt about 6 that, but I'm saying the data -- all I'm saying the data as 7 it's done in the rats could all be explained by the 8 particles. 9 ACTING CHAIRMAN FROINES: Well, let's go back to 10 the action item, as opposed to a discussion item. 11 Would you prefer we left in that phrase because -- 12 DR. BYUS: Yeah, I like -- but I'll -- 13 ACTING CHAIRMAN FROINES: We can leave it in 14 unless anybody strongly objects. 15 DR. FRIEDMAN: Could you point it out again. I've 16 lost it. 17 ACTING CHAIRMAN FROINES: It says the sentence now 18 reads -- 19 DR. FRIEDMAN: What item is this? 20 ACTING CHAIRMAN FROINES: Item 16, page four. 21 Results of inhalation -- and it's been moved up to 22 15. Results of the inhalation bioassays in the rat and with 23 lesser, something, certainty in the mice, have demonstrated 24 the carcinogenicity of diesel exhaust in animals, although 25 the mechanisms by which diesel exhaust induces lung tumors PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 144 1 in the rat are not certain. 2 DR. WITSCHI: Actually you should really just, to 3 be honest in saying the mechanisms by which diesel exhaust 4 induces lung tumors in animals. 5 ACTING CHAIRMAN FROINES: Okay. 6 DR. WITSCHI: Remains uncertain. 7 ACTING CHAIRMAN FROINES: That's better. 8 DR. FRIEDMAN: Doesn't that agree with you, Craig? 9 DR. BYUS: It does. That's why I liked it in 10 there. I don't disagree with what everybody is saying, I 11 just want to make sure that we don't -- it is important. 12 ACTING CHAIRMAN FROINES: Back to you, Stan. 13 DR. GLANTZ: In No. 18 -- before I comment on the 14 change, I think we should make there, one change I think 15 should be made to Part B of the report is that in Chapter 7 16 the quantitative risk assessment, I really think the 17 assessment based on animal data gets in the way of the 18 report. 19 Several of the commenters took exception to it. 20 And we don't use it in the end and I think it's 21 very confusing. 22 And what one thing I would suggest is that the 23 part that the sections in Chapter 7 that deal with the 24 animal risk assessment be moved to an appendix to get them 25 out of the way. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 145 1 And that the animal risk assessment numbers that 2 are in the figure, I think it's figure 7-10, be taken out of 3 that figure. 4 I think if OEHHA wants to present the results of 5 the calculations for people's information that's -- I don't 6 have a problem with that, although -- but I really think it 7 makes the report hard to follow. 8 And I think the criticisms of the use of the 9 animal numbers that came in and the comments were well 10 taken, especially since the human data, I think, is better. 11 So having made that suggestion, I would change No. 12 18 by deleting the first two sentences. 13 ACTING CHAIRMAN FROINES: Wait, wait, wait. 14 Are you suggesting, are you making a 15 recommendation before you get to 18? 16 DR. GLANTZ: Yeah. 17 ACTING CHAIRMAN FROINES: That the animal stuff 18 gets moved to an appendix. 19 DR. GLANTZ: The animal stuff in Chapter 7. 20 ACTING CHAIRMAN FROINES: George, what do you 21 think? 22 DR. ALEXEEFF: It's okay. 23 DR. FUCALORO: It's my impression that the animal 24 material was in that chapter historically because I think 25 you were using those data for your risk assessment, then PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 146 1 when you decided not to, the material remained in that 2 chapter. I think it should be set aside, perhaps in an 3 appendix. 4 DR. GLANTZ: I wouldn't be that unhappy to see it 5 disappear entirely. 6 ACTING CHAIRMAN FROINES: Anyone disagree with 7 that move? 8 DR. KENNEDY: No. I think it's a good idea. 9 ACTING CHAIRMAN FROINES: Peter is a plus. Peter 10 2 is a plus. And then plus. And then there's clearly 11 support from the non -- 12 DR. BLANC: Well -- 13 DR. GLANTZ: I'm not saying delete it. 14 DR. BLANC: No, no. I think that the appendix 15 proposal is more useful. 16 And in the same vein, the last iteration of the 17 draft document appeared before the EPA February '88 18 document, and I wonder -- '98 document -- I would wonder 19 whether or not in that same appendix you could then comment 20 on the EPA mouse-based risk guesstimation as a -- you can 21 put that in there too, and then you would at least be 22 alluding to that. I don't feel strongly about that. 23 ACTING CHAIRMAN FROINES: That's a good idea. I'd 24 support that. 25 DR. BLANC: By the way, I think that's another PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 147 1 reason why it's good to get mice into that other phrase that 2 we put them in, because after all, being used by the -- 3 ACTING CHAIRMAN FROINES: George, you know what's 4 being said? 5 DR. MARTY: EPA's lower end of the range. 6 DR. ALEXEEFF: There's just one clarification. 7 We don't believe there is a mouse-based risk 8 estimate in the US EPA document. It is a rat-based -- 9 DR. BLANC: Is that an error then in their text? 10 DR. FUCALORO: I thought they said rat-based, but 11 I could be wrong. 12 ACTING CHAIRMAN FROINES: Well, Stan -- 13 DR. GLANTZ: I'd like to say, because we want to 14 approve the report today, and I don't want to get 15 something -- open up a substantive thing which could then 16 cause trouble, if it's an editorial change that the chair 17 can approve on the panel to put a comment in on the EPA 18 report, I don't care one way or the other. 19 But I think the important point is to move the 20 stuff in Chapter 7 dealing with animal-based risk assessment 21 into an appendix and make it clear, as several of the 22 commenters suggested, that this is being presented for 23 information and comparison purposes with other studies, but 24 the risk assessment doesn't use the animal. 25 ACTING CHAIRMAN FROINES: George, listen. You and PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 148 1 Stan stop doing that. The action item is that you're moving 2 the material on animals into Chapter 7. 3 DR. GLANTZ: No. 4 ACTING CHAIRMAN FROINES: Into the appendix. 5 DR. GLANTZ: The animal material in Chapter 7. 6 ACTING CHAIRMAN FROINES: Let me do this. I can 7 do it fine. 8 The second thing we would like you to do is to 9 look at the EPA risk assessment and look at the discussion 10 of the mouse data and whether it's included in the risk 11 assessment. 12 If there's particularly relevant information that 13 you think is worth commenting on, then do so in that 14 appendix. 15 And if you think there are major policy or science 16 questions that need to come back to the panel, do so, but 17 try and not do that. 18 DR. GLANTZ: No, no. 19 I would like to amend -- no, no. I would like to 20 say if there are major policy or scientific issues, don't 21 put them in the report. I don't want to have to go back 22 and -- 23 ACTING CHAIRMAN FROINES: Well, those of us who 24 believe in mice are more oriented towards having it in there 25 if we can. So, George and I will communicate on this and PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 149 1 we'll communicate and if we need a -- if it -- 2 DR. GLANTZ: I would say if it has to come back -- 3 if it can be done and it's simply an editorial thing, that I 4 don't care. 5 But I think if it's something of sufficient 6 magnitude that would have to come back to the panel, I would 7 argue not to put it in. 8 ACTING CHAIRMAN FROINES: I think that if we find 9 something that's significantly important it should come back 10 to the panel, because we would rather not somebody on the 11 outside sue us and force us to do the same thing. 12 Let's handle it appropriately. And I guarantee 13 that 95 -- 99 percent of the chance is that you'll never see 14 it again. 15 DR. GLANTZ: Okay. 16 DR. FRIEDMAN: If it has to come back to the panel 17 will there have to be another public comment period? 18 ACTING CHAIRMAN FROINES: Yeah. You guys are 19 escalating, aren't you? 20 DR. GLANTZ: I think that if you can -- 21 ACTING CHAIRMAN FROINES: We can handle this. 22 We'll make a recommendation. 23 DR. GLANTZ: I will accept what you're suggesting 24 with the caveat that if it has to come back to the panel, 25 you won't do it. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 150 1 MS. SHIROMA: Could I get a clarification on this? 2 From listening to the discussion it sounds like 3 you would like the information moved in Chapter 7 to the 4 appendices, and then to add some clarification on what the 5 US EPA did? 6 ACTING CHAIRMAN FROINES: No. To review what US 7 EPA did and determine if there's any information that would 8 be germane to that section. 9 DR. GLANTZ: Actually, I don't like that, because 10 I want -- I think there's a point where you have to finish. 11 And what I'm -- and I think that's just a 12 different point. 13 What I'm -- what I want to do -- and this is 14 getting off the point talking about mice and rats. What 15 I -- the reason I'm making the suggestion is because I want 16 to make it very clear that the risk assessment is based on 17 the human data. And I really think the animal-based risk 18 adjustment just gets in the way. The human data are 19 clearer, the human data are more germane to humans, the 20 quantitative risk assessment is simpler. 21 ACTING CHAIRMAN FROINES: But wait. Let me speak 22 to that. I think it's very -- 23 DR. GLANTZ: I'm not saying delete it from the 24 report. 25 ACTING CHAIRMAN FROINES: Come on, Stan, let me PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 151 1 finish. 2 I think you're right in every respect, except for 3 the fact that major mechanistic issues, specifically around 4 interspecies variability, has been raised. 5 There is some quite important scientific issues 6 that diesel has raised around animal testing. 7 If there is something in the EPA document that 8 helps illuminate that issue, then I think as a matter of 9 science we have an obligation to incorporate that. 10 And it may be more troublesome, but I think this 11 is not simply a regulatory process. This is a risk 12 assessment where we try and look at all the data and we try 13 and look at how the data and animals relates to humans. 14 And I think that by simply saying the human data 15 is better is to misunderstand some of the complexities of 16 the mechanistic issues around the animals. 17 So I would still argue that if there's something 18 in there that's useful, it could be put in, and if it -- and 19 I suspect it won't have to come back, because it can be done 20 as a quote. It could be kind of done as a quote from the 21 EPA document. It's not something that George is going to 22 write some new creative thing from. So it shouldn't be a 23 problem at all. 24 DR. GLANTZ: Okay. Then I will stop. 25 Getting back to No. 18, what I would do then is I PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 152 1 would delete the first three sentences of the paragraph and 2 then so that the first sentence of the paragraph would read, 3 there are data from human epidemiological studies of 4 occupationally exposed population which are useful for 5 quantitative risk assessment. 6 And then I would delete everything down to where 7 it says based on a variety of exposure scenarios. The range 8 of resulting estimates of cancer risk, and then I would 9 insert in parentheses, upper 95 percent confidence interval, 10 or whatever it was you had on the slide, which was clearer. 11 And then I would delete the last sentence, because 12 I think that the Table 3 that you provided, which while very 13 interesting, should be incorporated into the report, not the 14 findings. 15 And I think you should incorporate that Table 3 16 into the report with the other additions that you showed us 17 today, the Steenland study and other study. 18 And then I would add a reasonable point estimate 19 of the unit risk is 4 times 10 to the minus 4. 20 So the paragraph would read -- 21 ACTING CHAIRMAN FROINES: I'm sorry. Could you go 22 over your changes. 23 DR. GLANTZ: First three sentences are out. 24 And then the next sentence stays. 25 And then beginning with -- PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 153 1 DR. BLANC: Which is the next sentence? 2 DR. GLANTZ: The next sentence which says there 3 are data. That stays. 4 And then from on balance down to where it says 5 population due to diesel exhaust, I would delete. It's the 6 third-from-the-bottom line. 7 DR. FUCALORO: Including population, including the 8 sentence in which that -- 9 DR. GLANTZ: Yeah. I would delete everything down 10 to where it says based on a variety. 11 And then after cancer risk, in parentheses, I 12 would put, 95 percent upper confidence interlevel, or 13 however it was on the slide they showed. 14 And then I would delete the last sentence and add 15 the sentence, a reasonable point estimate of the unit risk 16 is 4 times 10 to the minus 4. 17 ACTING CHAIRMAN FROINES: Are you subtracting out 18 a comparison of estimates of risk can be found in Table 3? 19 DR. GLANTZ: Yeah. I would take that out. 20 ACTING CHAIRMAN FROINES: No. I disagree strongly 21 with that. 22 DR. GLANTZ: Table 3, I think that should go in 23 the report. I mean -- 24 ACTING CHAIRMAN FROINES: I see. You're saying -- 25 DR. GLANTZ: I think Table 3 should be in the PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 154 1 report. 2 ACTING CHAIRMAN FROINES: No. I think it should 3 be in the report and I think it should be in our findings. 4 Because our findings show the range of risk assessments that 5 have been conducted, and I think I'm going to present this 6 to the Board and I want to have that table in front of me, 7 because I want to show them the breadth of -- it doesn't do 8 any harm to have a table that shows the breadth and the 9 scope of the risk assessments. 10 DR. GLANTZ: All right. I just think -- all 11 right. 12 I mean, but in any event it should be in the 13 report. 14 ACTING CHAIRMAN FROINES: No doubt. 15 DR. GLANTZ: With those other two studies. I 16 think it gets in the way here, but I'll defer to you. 17 ACTING CHAIRMAN FROINES: So you're at the crucial 18 point. 19 DR. GLANTZ: No. 18 would read the following. 20 There are data from human epidemiological studies 21 of occupationally-exposed populations which are useful for 22 quantitative risk assessment. Based on a variety of 23 exposure scenarios, the range of resulting cancer -- or 24 resulting estimates of cancer risk, parentheses, 95 upper 25 confidence interval, is 1.3 times 10 to the minus 4, to 2.4 PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 155 1 times 10 to the minus 3, Table 2. A reasonable point 2 estimate of the unit risk is 4 times 10 to the minus 4. A 3 comparison of estimates of risk can be found in Table 3, if 4 you really want it. 5 DR. BYUS: You better say lung cancer. 6 DR. GLANTZ: Yeah, lung cancer. I agree with 7 that. 8 ACTING CHAIRMAN FROINES: George, before we get 9 into the more difficult question, when we go through and 10 have Kyle Steenland's and Stayner's document and Kathy 11 Hammond's work with the meta-analysis and Allan Smith's 12 work, those are four new pieces of information, does the 13 range of risk stay to be to these values or will they 14 include any of the -- will those all fall within this range 15 or does the range change based on those four values? 16 DR. ALEXEEFF: They all fall within the range. 17 ACTING CHAIRMAN FROINES: They do. 18 DR. ALEXEEFF: Yes. Based on what was suggested 19 earlier for in terms of the -- we did preliminary 20 calculations following Dr. Blanc's suggestion, and that 21 would stay within the range. 22 ACTING CHAIRMAN FROINES: So that with Allan 23 Smith, Kyle Steenland, Les Stayner, Allan Smith, those four 24 new values that are not based on Garshick, they're not based 25 on Garshick, they would all stay within this range as you've PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 156 1 defined it. That's a yes or no question. 2 DR. ALEXEEFF: The answer is yes. 3 ACTING CHAIRMAN FROINES: The answer is yes? 4 DR. ALEXEEFF: Yes. 5 ACTING CHAIRMAN FROINES: You're comfortable with 6 that? 7 And you understand what I'm now saying is that the 8 range of risk in our Table 3, the range of risk that we list 9 will include those values? 10 DR. ALEXEEFF: Right. 11 ACTING CHAIRMAN FROINES: And we will be -- we 12 will see that they are similar? George? 13 DR. ALEXEEFF: Uh-huh. 14 ACTING CHAIRMAN FROINES: And that you can put a 15 sentence in to say these four values taken with the Garshick 16 data are essentially internally consistent. 17 I'm trying to get a weight of evidence here. Do 18 you understand I'm trying to -- 19 DR. ALEXEEFF: Yes. 20 ACTING CHAIRMAN FROINES: I'm trying to show it's 21 not all Garshick. 22 DR. BLANC: Can you tell me, following up on 23 John's comment, if you use the value of 250 micrograms in 24 the algebraic calculation based on the pooled relative risk 25 of 1.4, what that midpoint is? PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 157 1 DR. ALEXEEFF: Yeah. The new point would be 2.6 2 times 10 to the minus 4. 3 DR. BLANC: Would be that value. 4 ACTING CHAIRMAN FROINES: Okay. But I'm not -- 5 wait. I'm coming to you. But I want to make sure that I'm 6 clear. 7 DR. ALEXEEFF: Yes, you're clear. What you're 8 saying is if we consider our range of risk, which is the 9 range that we calculated using essentially -- well, first 10 starting with the two railroad worker studies. Now if we 11 also consider the work, the revised estimate from the 12 meta-analysis, plus the Steenland study, plus the Stayner 13 information, plus Allan Smith's calculation, are those 14 numbers all falling with our estimated range of risk, and 15 the answer is yes. 16 ACTING CHAIRMAN FROINES: Yes. 17 And then I want you to put a sentence in that 18 draws attention to that, that you have railroad worker 19 studies and coal miners and you have meta-analysis and you 20 have railroad workers, you have a wide range of industries 21 and occupations which have been done by different people and 22 have come out with consistent, which appears to be 23 consistent, results and that you take that as being 24 meaningful. 25 DR. ALEXEEFF: Yes. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 158 1 ACTING CHAIRMAN FROINES: Because I think that 2 there has been a lot of concern expressed about the 3 overemphasis on the Garshick study, and here you have a 4 wonderful opportunity to show how whether it be coal miners 5 or truck drivers or railroad workers or the meta-analysis 6 covering all the studies, that you have reasonably 7 consistent results based on solid methodology. And I think 8 that's very worth drawing attention to. 9 Now I'm finished. I'm finished. And I'm now 10 going to go to what -- to Stan's issue, which I take it is 11 controversial. 12 DR. GLANTZ: No. 13 DR. ALEXEEFF: Before you do that, I'd like to 14 discuss a couple other issues related to that. 15 ACTING CHAIRMAN FROINES: Okay. I think that that 16 also means that you can consider dropping out or putting in 17 an appendice or doing something with some of those risk 18 assessments that are based, that are a little bit softer. 19 DR. GLANTZ: Wait. I had the floor. 20 DR. ALEXEEFF: I think -- let me just clarify one 21 thing. We have this table. The table that we're calling 22 Table 3. Okay. 23 And it sounds to me what you're suggesting is that 24 we have a Table 3 with this information. 25 At the same time our range of risk table, which PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 159 1 would supplement that by adding this other study 2 information, is that correct? Or is it simply we're talking 3 about Table 3 and pointing to this Table 3? Let me just 4 make sure we're talking about -- are we actually altering -- 5 because the way we have explained our range of risk is look 6 at this table, here's the calculations. So Table 7-10 as 7 example or 1-1, if you're looking at the executive summary. 8 So one possibility would be to add this other 9 information as part of the range of risk. 10 The other one is simply to use it as an adjunct 11 table and point to it. And I guess that's the only 12 distinction I'm not clear on. 13 DR. GLANTZ: If I could, what I think you should 14 do is the former. That what I'd like is that in the table 15 in the main text and in the figure, I think it's Figure 16 7-10, that you could take out the animal. 17 DR. MARTY: 7-4. 18 DR. GLANTZ: 7-4. You should take out the animal 19 stuff and add in these other couple of estimates, the four 20 estimates that John has talked about. 21 And the -- it won't change the summary statement 22 here at all. 23 And I think now we're basing things on a much 24 broader set of information. And so that's -- and I think 25 the report and the executive summary needs to be revised is PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 160 1 appropriate to make that point. 2 I don't think it should be just be an adjunct of 3 it. It should be viewed as consistent with all the other 4 stuff that's in there. 5 DR. ALEXEEFF: So we would be revising Table 3, 6 plus we would also be revising in our document our Table 7 7-10 or 1-1 where we actually have our risk range. Is that 8 what the suggestion is? I just want to make sure I 9 understand. 10 DR. GLANTZ: That's what I would suggest. But 11 also there is that figure in there with the -- 12 DR. ALEXEEFF: Plus the figure, right. Make the 13 figure consistent with the table, I think is what you're 14 suggesting. 15 ACTING CHAIRMAN FROINES: Peter is next. 16 DR. WITSCHI: I expressed earlier some concerns 17 about that limited database. Some of them have been 18 alleviated. But those two papers we just got by Steenland 19 and by Stayner, have they to be appeared in the peer review 20 literature, have to be published as such? 21 DR. BLANC: One is in the press in the American 22 Journal. 23 DR. WITSCHI: One is in press? Both are. Okay. 24 ACTING CHAIRMAN FROINES: Both are press. 25 DR. WITSCHI: So they have undergone peer review? PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 161 1 DR. ALEXEEFF: No, actually let me -- I'm not 2 hundred percent sure on the Stayner, maybe you can -- but 3 the Steenland is in -- the Steenland article is in press. 4 Okay. 5 And actually let me just clarify one other point 6 regarding the Steenland. 7 So is Stayner too, right. 8 Regarding the Steenland paper, Dr. Blanc asked a 9 question whether or not this was a new relative risk and if 10 it was included in our meta-analysis. 11 So the answer is that the relative risk used in 12 the Steenland paper is the one -- is in our meta-analysis 13 already. It's the 1990 relative risk. 14 What is new in the Steenland paper is the exposure 15 analysis of the truck drivers and coming up with a unit risk 16 value. That is what's different and new. But the relative 17 risk is the one that's published. 18 DR. BLANC: What was it, 1.3? 19 DR. ALEXEEFF: That I can't recall. I can't 20 recall what that relative risk was. But it's in that -- 21 ACTING CHAIRMAN FROINES: Can I say, these numbers 22 are not to be used in the table until we -- I mean, we need 23 to get clearance from the journal and from the authors to 24 incorporate them into our document, so there could be a time 25 gap. We can't take and we can't quote these. This is not PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 162 1 to go to the press. We can't -- these are -- one of them is 2 in the Federal Register, but I think that these are 3 documents that are about to emerge. 4 DR. GLANTZ: I think you should check with them, 5 but it's not -- the fact is they provided them in press 6 things and I mean -- 7 ACTING CHAIRMAN FROINES: I'll work that out. 8 Don't worry about it. 9 DR. GLANTZ: Well, anyway, so the other change I 10 would make to Table 3 is first three lines about the 11 comparative potency. I would take that out. 12 ACTING CHAIRMAN FROINES: Wait. I can't -- 13 DR. FUCALORO: Excuse me. Where were you now? 14 DR. GLANTZ: I'm back at Table 3. 15 ACTING CHAIRMAN FROINES: Can we go back to your 16 point, though. As much as you would like it to go by 17 unnoticed, I think -- 18 DR. GLANTZ: We can come back, but I'd like to 19 just try and finish making the points. We can go discuss 20 that. 21 Just to finish the point of focusing things on the 22 human data, in the Table 3 I think the comparative potency 23 lines of that should be removed. 24 I thought that argument was -- I mean, it's back 25 to animals. I think it's not as strong and it just confuses PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 163 1 matters, so I would like that deleted from Table 3. 2 ACTING CHAIRMAN FROINES: I've lost it. 3 DR. GLANTZ: Table 3 has a bunch of different 4 epidemiological -- the summary results of -- 5 ACTING CHAIRMAN FROINES: You want to take out the 6 three comparative potencies? 7 DR. GLANTZ: Yeah. 8 ACTING CHAIRMAN FROINES: Keep them in the text, 9 George. 10 DR. GLANTZ: You can keep it in the report, but 11 take it out of the table. 12 ACTING CHAIRMAN FROINES: I think the other thing 13 I want to take out, I want to be responsive to Peter 14 Witschi, and that is we have McClellan in here twice, one of 15 which is a EPA quote, one of which is our quote of him. I 16 would argue that I would support Peter and take out ours, 17 and since we have this same thing as the EPA document quote. 18 Peter, you agree? 19 DR. WITSCHI: Yes. 20 DR. ALEXEEFF: Take out whose? 21 ACTING CHAIRMAN FROINES: There's no sense having 22 the same risk assessment in twice. 23 DR. GLANTZ: The fourth from the bottom, the 24 McClellan railroad workers, delete that from the table. 25 DR. ALEXEEFF: We didn't use it in our risk PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 164 1 assessment, so I think it should be deleted, because we 2 took -- he wrote us a letter asking us not to use it, and we 3 did not. So putting it in the table would suggest that we 4 did, and it would be confusing. 5 DR. BLANC: Can we come back to your suggestion 6 that the best point estimate is four? I'm sorry -- 7 DR. GLANTZ: I didn't say best. I said a 8 reasonable point estimate. 9 DR. BLANC: A reasonable point estimate. 4 times 10 10 to the minus 4? 11 DR. GLANTZ: Yes. 12 DR. BLANC: Could it -- it would be useful for me 13 to hear you state to me why you think that's the most 14 reasonable number. 15 DR. GLANTZ: Because when you look at -- the way I 16 came up with that number was when if you look at figure 7-4, 17 which is the results of all of the different analyses, and 18 there are all kinds of different assessments or exposures 19 assessments, that seemed about the middle of it. 20 And I was actually struck in reading this at how 21 insensitive the unit risks were to the presumed exposures. 22 And it seemed to me that a reasonable number to 23 use, because people are going to want to know what we would 24 suggest and we've spent years looking at this is the middle, 25 and four is in the middle, and I talked with George about PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 165 1 this, and he -- that was a number they came up with too. 2 DR. FRIEDMAN: These upper 95 percent confidence? 3 DR. GLANTZ: Yes. 4 DR. FRIEDMAN: Well, then I wouldn't use the 5 term -- you can use the term, but not point estimate, 6 because that will -- people get confused because they think 7 of that as not as the confidence limit. 8 DR. GLANTZ: Well, then just say a reasonable 9 estimate of the unit risk. Yeah. I'm happy with that. In 10 fact, that's what I had originally written. Just say a 11 reasonable estimate of the unit risk is. It's not even 12 saying it's the best one, but it's a reasonable one. 13 ACTING CHAIRMAN FROINES: Paul, in seven minutes I 14 want to take a break. 15 DR. BLANC: Well, I want to say two things in 16 response to that. 17 One is I think that's an excellent idea that we 18 say what we think a reasonable estimate is. 19 Secondly, I think that we should not have a 20 reasonable estimate which is lower than the lower 95 percent 21 confidence level of the various -- of any of the various 22 models that we're suggesting are potentially viable. 23 There were in the series of roof models, I don't 24 have the table in front of me, one of the roofs, you know 25 that A, B, C, D thing, do you have that handy? Can you just PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 166 1 put that up? 2 DR. ALEXEEFF: The numbers? 3 DR. BLANC: The numbers. 4 DR. ALEXEEFF: Or the pictures? 5 DR. BLANC: The numbers. 6 DR. ALEXEEFF: Melanie will put that up. 7 DR. BLANC: First of all, the estimate that's 8 going to -- that I've written -- that I wrote down earlier, 9 that came out of Steenland is 7.7 times 10 to the minus 4th. 10 DR. ALEXEEFF: Correct. That's the number that we 11 had. 12 DR. BLANC: Did I get that correct? 13 So we would be below their estimate for that. 14 And then some of these -- some of the lower 95 15 percent estimates of these models are also above 4 times 10 16 to the minus 4th. 17 So I think to be consistent, I'm not trying to 18 split hairs, but I think we should go up slightly more than 19 that in order not to be inconsistent with our own 95 percent 20 modeling on the lower end. I think we're obliged to be 21 above the lower end of 95 percent confidence intervals and 22 some of these model assumptions, albeit not in -- so I think 23 you're in the ballpark, but I think it needs to be up a bit 24 higher. 25 DR. ALEXEEFF: Can I clarify a couple points on PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 167 1 this? 2 One is the four, I think that that's what Stan is, 3 Dr. Glantz is referring to is the geometric mean of our 4 previous upper 95 percent confidence limits. So it is a 5 geometric mean of the upper bounds. 6 DR. FUCALORO: May I ask you a question? Is this 7 a standard procedure to get the geometric mean? 8 DR. ALEXEEFF: We've often calculated a geometric 9 mean, yes. But it's not -- 10 DR. FUCALORO: Then if we use that number, somehow 11 I think Stan has some point here he's trying to get is that 12 we should have a number that we can quote rather than just a 13 range. I think that's his motivation. 14 But then maybe instead of using the word 15 reasonable, let's just say how we arrived at the number. It 16 was the geometric mean between the limits of the range, or 17 something like that. 18 DR. ALEXEEFF: Right. There's two points on that. 19 In the past what we have done, as we have often 20 found a single study or a value that we felt was the most 21 compelling and that is what we suggested in the range of 22 risk. 23 In this case the view is more of an overall review 24 of all the information. 25 In the past we've had a geometric mean. That is PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 168 1 not necessarily to say it's the best value. We tried to be 2 clear in the document that we're saying it's not necessarily 3 the best value. It just gives a sense of where the -- when 4 you have a table of numbers like this, where the balance 5 point is. 6 DR. FUCALORO: I understand that. And I'm saying 7 by just stating exactly how you arrived at that number, I 8 think that on the face of it explains it. 9 Now, whether or not someone says why did you do 10 that, well, you can say ask Stan, or ask you. 11 But the question is that if there is a statistical 12 methodology which comes to the best value, let's hear it and 13 let's use it. 14 But if there is none, but some sort of policy or 15 some sort of practice of using the geometric mean, let's 16 state that we did and use that. 17 I would say that even in this case, there's 18 probably less meaning to that number because it is a mixture 19 as opposed to an individual compound, and a mixture that 20 whose composition may change over time. 21 So this number probably has less impact or less 22 importance. 23 However, if Stan thinks that that number somehow 24 makes it convenient to people to state something, I'll go 25 along with that, but let's just state what it is and not put PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 169 1 too much confidence in that number for the reasons I state. 2 DR. BLANC: Well, I want to correct something. 3 First of all, I had see the table briefly before 4 and I now realize that it wasn't the two sides of the 95 5 percent. The one is the upper and other is the best 6 estimate. So from that point of view, I'm sorry for 7 bringing that up. 8 But I wonder how the 4 times 10 to the minus 4th 9 changes when you plug in not just these numbers in your 10 best, but you add the Steenland and all that. I just want 11 to make sure that we're not -- because we are going to come 12 out lower than Steenland's estimate that way. He's at 1.7. 13 He's at -- I'm sorry. He's at 7. 14 DR. ALEXEEFF: Steenland's value is 7.7 times 10 15 to the minus 4. 16 DR. BLANC: We're proposing -- 17 DR. FUCALORO: The geometric mean is not 4, it's 18 5.5. 19 DR. ALEXEEFF: Correct. Yeah. There's a point to 20 make here and that is, as we indicated, there were some 21 suggested changes in a couple of these calculations, 22 particularly the numbers like in the scenario A. So if you 23 look at scenario A, that number is different slightly from 24 the value that's in the document, because of comments that 25 came in. So it would end up being slightly higher, about PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 170 1 5.5, 5.6. 2 DR. FUCALORO: 5.58. But if you want one 3 significant figure you get to 6, which is in very close 4 agreement with -- 5 DR. ALEXEEFF: On the other hand, if we included 6 the Stayner information and the Steenland information as the 7 table, do we have to recalculate the geometric mean again, 8 is all I'm referring to. 9 ACTING CHAIRMAN FROINES: Why don't you leave them 10 out. 11 DR. GLANTZ: Well -- 12 ACTING CHAIRMAN FROINES: Leave them out. 13 DR. GLANTZ: Of what? You just said to put them 14 in. 15 The only point, what I would suggest doing in 16 light of this discussion is the following. 17 I don't think we need to talk about the geometric 18 mean in the findings, but I think it should be explained in 19 the report. Okay. 20 And I think what you should do is just correct 21 these numbers, as you just said, add in these other four 22 points, compute the geometric mean, round it to one or two 23 digits, probably one, and then use that number, and then it 24 will be around five, four or five, six. 25 DR. FUCALORO: Geometric mean from a set of PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 171 1 findings. 2 DR. GLANTZ: Make it clear how you did it. 3 DR. FUCALORO: I actually did it from the two 4 extremes. That's how I came up with 5.6. But if there are 5 more data you can -- 6 DR. GLANTZ: As Tony said, the difference between 7 six and seven and five isn't that much in this context. But 8 I think what is important is to give people some guidance as 9 to what we think a reasonable estimate of the unit risk is, 10 because I don't think we should take the highest upper 95 11 percent number because that's, you know, I just think that's 12 biased. And nor do I think we should take the lowest one. 13 And this will give us a reasonable middle estimate. 14 And so you can explain, put a little section in 15 the report or a paragraph at the right place explaining how 16 you came up with it, and then put the appropriate number in. 17 DR. FUCALORO: Then you can worry about defending 18 it. 19 DR. BLANC: Well, I just want to say again, I 20 completely agree it's not that I objected to saying what we 21 thought it was. I just thought it was obtuse to me how that 22 number had been arrived at, and it didn't seem to be totally 23 consistent with all the data. 24 DR. GLANTZ: Okay. 25 DR. BLANC: And I would say that when you go PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 172 1 through this exercise of generating this number, which is 2 going to be in the ballpark of between 1.5 and -- I'm sorry, 3 between 4 and 8 times 10 to the minus 4th, that what you 4 take the -- if you do it on the basis of taking some kind of 5 mean of these numbers, I don't think each of the various 6 models should be weighted such that you have 15 different 7 things going at the model. Take a mean of those four 8 different roof models. Take a mean of the other roof and 9 ramp models from these various data. Otherwise you're 10 overweighting things from one data set and one approach. 11 So I think you can take the average of your 12 various roof models, the average of your various ramp 13 models, the average for the cohort for the case control. Do 14 you follow what I'm saying? 15 DR. ALEXEEFF: Yes. 16 DR. BLANC: And then average those averages with 17 your other sources, the one from the 1.4 meta-analysis 18 relative risk based on a mean of 250 micrograms, the one 19 from Steenland, et cetera. 20 DR. GLANTZ: It will probably come out the same as 21 what Tony just did, but I think that's the correct 22 procedure. 23 DR. FUCALORO: Whatever you do, be prepared to 24 defend it, defend your method. 25 DR. ALEXEEFF: I think what we will do is we'll PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 173 1 combine -- we'll average the values based upon the studies, 2 so we'll average the case control values, average the cohort 3 study values. I think that's the most defendable. And just 4 say this is our average from that and average from that and 5 then we can average with the other values. 6 DR. GLANTZ: Geometric average. 7 DR. ALEXEEFF: Geometrically, yes. 8 DR. FUCALORO: Keep away from value-laden terms 9 like reasonable and that sort of thing. That would be my 10 suggestion. You can -- 11 DR. ALEXEEFF: I think we would just leave it 12 as -- we already have a discussion that it's a geometric 13 mean and we'll just explain that. 14 DR. FUCALORO: Exactly. 15 DR. GLANTZ: The reason I picked reasonable was I 16 was trying to avoid the word best. 17 DR. BLANC: I think for this kind of report, for 18 this kind of document, the word reasonable is fine. 19 I think, Anthony, you were referring more to what 20 they should say in the full-blown -- 21 DR. GLANTZ: So anyway that's what I would 22 suggest. 23 And that's -- and I have a few little odds and 24 ends things in the report, which I think are more editorial 25 that I can give them later. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 174 1 DR. FUCALORO: I just want to pass by for your 2 consideration changing the wording on the sentence which 3 begins based on a variety of exposure scenarios, and I'm not 4 exactly sure I know what that means, the range of resulting 5 estimates. 6 Is this what is meant by that? Maybe I'm wrong. 7 The estimated range of the lung cancer unit risk 8 factors determined from the epidemiological studies is? 9 DR. GLANTZ: That would be much better. I like 10 that better. 11 DR. FUCALORO: Did you get it? 12 MS. SHIROMA: Could you repeat that? 13 DR. FUCALORO: I'll just bring it over there. 14 DR. GLANTZ: Why don't you read it for everybody. 15 I think that's much better than the way it reads. 16 DR. FUCALORO: The estimated range of the lung 17 cancer unit risk factors determined from the epidemiological 18 studies is, then put in the value. 19 DR. ALEXEEFF: We would want to insert in there 20 that upper 95 percent confidence intervals. 21 DR. FUCALORO: That's what Stan is suggesting. I 22 think we all approved that. 23 ACTING CHAIRMAN FROINES: Okay. Stan, I want to 24 take a break for the stenographer, and so if you have other 25 points that are relatively minor you can just give them to PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 175 1 George or Melanie. 2 DR. GLANTZ: That's what I'll do. I'll just give 3 them to them. 4 ACTING CHAIRMAN FROINES: And so we're then going 5 to go next to Peter and Peter for -- and Tony, but he's 6 getting all his shots in. He's not hiding over here. I was 7 recognizing that. 8 So let's take a break. What we'd like to do is 9 then go to Peter and Peter and back to me and Tony and then 10 hopefully we can wrap up. I would like to try to wrap up by 11 4:00 o'clock if we think we can do it. Everything is going 12 so smoothly, it would seem like we can. 13 (Thereupon a short recess was taken.) 14 ACTING CHAIRMAN FROINES: No yawning. Okay. 15 We've moved on from Dr. Glantz and we're now 16 taking comments from Dr. Witschi. 17 George. 18 DR. ALEXEEFF: Just as a comment, we've looked 19 through that EPA report again. We haven't found a mouse 20 value, although they discuss mouse studies. So we don't 21 suspect we're going to find one calculated on the mouse 22 data. 23 ACTING CHAIRMAN FROINES: That makes everybody 24 happy except me, because I still believe the mouse is 25 positive. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 176 1 Peter. 2 DR. WITSCHI: Okay. I have a substantial problem 3 with assigning a unit risk diesel exhaust particles. 4 First of all, it's usually unit risk is associated 5 with properties of specific compounds, and as far as this 6 list is concerned, we have a mixture. 7 The second one, if you look at Table 2 the unit 8 risk value for diesel exhaust is pretty close to the one of 9 inorganic arsenic or benzo(a)pyrene or nickel or butadiene, 10 out of which all those compounds are probably just present 11 in traces of micrograms per cubic meter. 12 So having a unit risk of the mixture is the same 13 as the defined compounds. Somehow I would like to know what 14 it is in diesel then that makes it as potent as the other 15 agents are. 16 The third problem I have is what we are doing, 17 particularly if you look at point 19, the 200 to 3,600 18 additional cancer cases. We are taking something which 19 probably happened in the 1950s and 1960s, and this is 20 increased rates of lung cancer. We are multiplying this by 21 measurements we took in the '80s and more often than not, 22 those measurements are surrogates for diesel. Most of the 23 time they are just separate particle without having been 24 identified exactly as diesel. 25 And from this then we make projections for the PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 177 1 year 2000 and beyond. And this involves many many 2 assumptions and many many uncertainties. 3 And frankly it's just too much for me. There are 4 too many assumptions and there are too many uncertainties to 5 come down and give a cancer potency to diesel. 6 Particularly if you look at this thing in a 7 different way. This document has given us a hypothesis and 8 the hypothesis is that diesel causes lung cancer in men, and 9 that's a hypothesis that's testable, without having any 10 numbers. 11 I know it's beyond the scope of this panel, but 12 the way this happened, this could be test is by really 13 substantially reducing exposure of the general public to 14 diesel by dealing with all of those heavy polluters which 15 are still around, and by really cutting down on reduction on 16 emissions. And in other words to see whether diesel causes 17 lung cancer is a testable hypothesis, and we should test it. 18 That's all I have to say. 19 ACTING CHAIRMAN FROINES: Well, break it in two 20 pieces. 21 The first question derives from your concern about 22 establishing a unit risk value, and the second concerns the 23 actual cancer estimate of 200 to 3600, which is actually not 24 based on a single unit risk estimate, it's based on a taking 25 the two unit risk assessments and calculating them directly. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 178 1 DR. WITSCHI: I understand this, but this does not 2 change the principle. It does not change the principle. 3 ACTING CHAIRMAN FROINES: Okay. And so why don't 4 we have a discussion about the unit risk issue first. And I 5 don't know the best way to have it. 6 You've expressed two points of view. 7 DR. WITSCHI: Well, I also would like still to go 8 by 36653 -- 9654 E, that while absolute and undisputed 9 scientific evidence may not be available to determine the 10 exact nature and extent of risk from toxic air contaminants, 11 it is necessary to take action to protect public health. 12 In other words, to me it seems we can take action 13 to protect public health in the absence of a unit risk, 14 because a unit risk might not be scientifically as sound or 15 defensible as it is for example for individual compounds. 16 And the other one in the particular case we do not 17 need, because the evidence is just too good. 18 ACTING CHAIRMAN FROINES: Here's a legal matter. 19 We meet our obligation as a panel by either adopting a unit 20 risk or by accepting the range of risk. Our obligations are 21 met in either case. We are under no requirement that says 22 we must have a specific unit risk value. 23 Now, we have, with the exception of lead, we have 24 always had a unit risk value. 25 So that the real issue is does the panel feel that PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 179 1 the data before it in their report justifies establishing a 2 unit risk value. I think that's the question before us. 3 DR. GLANTZ: Well, I think since I suggested it, 4 yes. 5 And I agree with you that we should do No. 18 and 6 No. 19 and discuss those separately. 7 But the fact -- I don't agree with Hanspeter. I 8 think the evidence in front of us that diesel exhaust is a 9 lung carcinogen is very strong. 10 DR. WITSCHI: That's not what -- you heard me 11 wrong. 12 DR. GLANTZ: Hang on. Let me just finish. 13 I think that the evidence that we have that it is 14 a human carcinogen is exceptionally strong, and of all the 15 reports I've been on, worked on, on this committee, this is 16 one of the most thorough, more compelling, best cases, and I 17 think that the -- so the fact that there is a risk is, to 18 me, is certain as you can ever be in these things. 19 The reason that I suggested that we specify a 20 reasonable estimate is because the fact is that that's going 21 to happen as the discussion moves forward, and we've spent 22 the last several years looking at this going to endless 23 workshops, and I think that the idea of taking the geometric 24 mean of these different estimates is a very reasonable way 25 to come up with a suggested number. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 180 1 The thing that has struck me in reading the report 2 in terms of the human stuff is that how little scatter there 3 is actually and how little variability there is in the 4 estimates when you cut it many different way in the 5 meta-analysis. And I'm glad that we have decided to give 6 the meta-analysis more emphasis, because I actually think 7 that's more compelling than just hanging everything on one 8 of the Garshick or the two Garshick studies. 9 And I think that the thing that struck me is how 10 relatively insensitive the unit risk, the sort of the unit 11 risk estimate is, and I think that if -- that we are better 12 positioned to come up with a recommended value than anybody 13 else who has been in the process so far. 14 And every other report that we've done, we've come 15 to that conclusion, often based on much much much less 16 information and many more assumptions than are necessary 17 here. 18 The only real assumptions that are made are, you 19 know, which of these different exposure profiles is the 20 reasonable one to assume. And what the staff have done is 21 widely bracketed all possible things that would be 22 reasonable. And we're taking something that's in the middle 23 of that. 24 And so I think we're in fact making many fewer 25 assumptions in doing this than we have, you know, everything PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 181 1 else we've looked at since I've been on the panel. 2 DR. WITSCHI: Well, I'm not -- that's okay. I 3 mean, I never said it's not a carcinogen. 4 DR. GLANTZ: Yeah, I know. 5 DR. WITSCHI: I found actually among all the 6 things, those estimates and whatever it was, actually I 7 found Allan Smith's approach much more compelling than all 8 those assumptions and certainties and guesstimates that came 9 from developing the formal risk assessment, because that's 10 somehow I personally can relate to. That makes sense. 11 DR. GLANTZ: Well, you're not going to get 12 argument out of me. 13 But it comes out with about the same number, about 14 5 times 10 to the minus 4, 6 times 10 to the minus 4. 15 DR. WITSCHI: That's okay. 16 DR. GLANTZ: Okay. 17 DR. WITSCHI: I would be fine with. I just said 18 the unit risk is for a mixture is something I have a problem 19 with. 20 Take it only from Allan's standpoint, taking only 21 that ratio of 1.4 without then bringing exposure into the 22 game is, to me, much more convincing than starting to say 23 going into all this particles, they make the carcinogens out 24 there, so on and so, ramp, no ramp, proof and all these 25 kinds of things. To me, this one here is much more simple. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 182 1 ACTING CHAIRMAN FROINES: To you that would be 2 acceptable? 3 DR. GLANTZ: You come up with the same number both 4 ways, though, you know. 5 DR. FUCALORO: Well, I think as to be somewhat of 6 a diplomat in this, I mean, one could also put another item 7 in which points out Allan's approach and demonstrate that it 8 comes out to about the same number. 9 I think, though, it points to something, you have 10 another point here that I think is well taken, and when I 11 tried to get in earlier, maybe I can be more explicit about 12 it now, I admittedly will mix risk assessment and management 13 and I know that there's a fire wall between the two by law, 14 but allow me this for the moment. 15 Now, risk assessment and risk management use two 16 factors that they're interested in. One is a risk factor 17 and an exposure level. Normally for single compound toxins 18 all -- once the risk factor has been established, the only 19 thing one is concerned about is exposure level, trying to 20 reduce that using the best available technology. 21 While in this case I would argue that one has to 22 monitor also the risk factor, because the nature of diesel 23 exhaust will change with time. And I think that perhaps 24 wording that recognizes that, if it does not exceed our 25 authority, and I'm not sure I know if it does, would be PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 183 1 something that might find its way in our recommendation, 2 something saying that we recognize that not only does 3 exposure level have to be monitored, but also risk factor, 4 because that may be a changing number. 5 And what even confounds it more, and I think 6 Peter, Hanspeter will agree with this, is the number of 7 older diesel engines, you have newer ones, and so on, I 8 mean, it's a pretty complicated number to get at, but maybe 9 it can be arrived at with reasonable methodology. 10 ACTING CHAIRMAN FROINES: Well, I need help here. 11 DR. BLANC: Well, let me see if I can step in. 12 I think that Dr. Witschi's trepidations are 13 understandable from a philosophical point of view, 14 representing your philosophical approach to this, but I 15 don't think they are consistent with the charge of the 16 committee or of the process as it has gone forward over very 17 many months and I don't think there is any linguistic way to 18 satisfy your trepidation. 19 And I think that you're going to have, in the end, 20 just beg to differ with the conclusions of the panel, 21 because I don't think that taking out the risk estimation is 22 a viable option. 23 And really my question to you is what form would 24 you like your trepidations to be voiced? 25 DR. WITSCHI: Okay. Say that again, what form? PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 184 1 DR. BLANC: What form would you like your 2 trepidations to be voiced in? Because they are too global 3 to be addressed in the document, in our finding itself. 4 DR. WITSCHI: That's very simple. 5 The risk assessments saw the light of the day by 6 the famous benzene decision, where something just could not 7 be considered to be a carcinogen without demonstration of 8 adequate risk, which happened in 1983. 9 The language and presumably the mandate of the 10 committee, at least what it says here, also goes back to 11 1983. 12 Now we have 1998, and we have much more 13 information. We know much more about carcinogenesis, we 14 know much more about human carcinogenesis, and my contention 15 is why going through all these difficult things and coming 16 up with a number, which is fraught with so many 17 uncertainties, when we are dealing with something we know 18 it's a human carcinogen and can do something about it 19 without even having creating a number which is based on many 20 many assumptions. It's that simple. 21 DR. FUCALORO: In other words, you just don't 22 think we need to report a risk factor? 23 DR. WITSCHI: Right. 24 DR. FUCALORO: I mean, that's what you're saying 25 and you're using the language in the law which allows for PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 185 1 that to happen? 2 DR. WITSCHI: Yes. 3 DR. FUCALORO: I understand that. 4 DR. BLANC: I understood that that was your 5 comment. 6 I'll come back and say again that is not going to 7 be the prevailing view on this committee, I do not believe. 8 Then I am trying to find some way at the same time 9 to take into account your trepidations while we move forward 10 with our work. 11 DR. WITSCHI: We do not have to be unanimous. 12 DR. BLANC: What's that? 13 DR. WITSCHI: We do not have to be unanimous in 14 adopting the findings. 15 The only thing I'm taking issue with is nothing 16 else but point 18 and 19 in the findings. And it's going to 17 be the prerogative of the chairman how he's going to phrase 18 the question. 19 My disagreements to those two points would in no 20 way preclude me voting for diesel exhaust being a toxic air 21 contaminant. It clearly fills the criteria. 22 So I leave it up to the imagination of Dr. Froines 23 eventually to come up having listened to me, to come up with 24 an appropriate question. 25 DR. FUCALORO: In other words, I think you are PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 186 1 clear, he can phrase the motion such that you're given the 2 freedom to vote that it is a toxic air contaminant, but not 3 force you to vote for the number that's the item 18. 4 DR. WITSCHI: Yes. 5 ACTING CHAIRMAN FROINES: I would prefer if we 6 could come to a unanimous agreement among the ourselves. I 7 think it would be better for the panel. 8 DR. BLANC: Let me come at this a different way, 9 then, or ask the question a different way. 10 If we at the end of the day take this memorandum 11 as we've modified it through various comments, and we say we 12 would now -- we would like the record to show that the panel 13 has reached a consensus on this memorandum, and I turn to 14 you and said I know that you're not thrilled with certain 15 aspects of this because of deeper philosophical beliefs 16 about how one goes about calculating risk, or whatever, 17 however I say it, but can you live with this as a whole, 18 despite whatever trepidations you have? Would your answer 19 be yes, I can live with as a whole? 20 DR. WITSCHI: I really don't think that that's not 21 so much philosophy, it's what I think is some criteria 22 applied to science. I probably have -- I cannot live with 23 that unit risk for diesel exhaust. 24 DR. BLANC: Well, then, John, I think at that 25 particular difference on that particular point is, with all PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 187 1 due respect, probably irreconcilable and what the options 2 are either simply to state that we've achieved consensus 3 except on one point where there was one member of the panel 4 who dissented from the view on this one point, or some other 5 mechanism for noting that, but I don't believe that you're 6 going to achieve consensus on point 18, or whatever. 7 ACTING CHAIRMAN FROINES: And we haven't taken a 8 vote on this principle, so it's not clear what the consensus 9 is. 10 But the other matter, let me go back to Stan, 11 though, or to the other panel members. We have a range of 12 cancer risk of 1.3 times 10 to the minus 4, to 2.4 times 10 13 to the minus 3. The 4 is already, but there's been no 14 disagreement about. What do we benefit by coming out with a 15 specific number? 16 DR. GLANTZ: Well, the reason that I think we 17 should do is that we've always done it and I think -- 18 ACTING CHAIRMAN FROINES: That's not true. 19 DR. GLANTZ: Well, except for lead, which was a 20 report that was mired in political problems. 21 ACTING CHAIRMAN FROINES: But let me preface it by 22 saying, at one point I wrote a document and I sent to all of 23 you and said that we have an obligation under the law to 24 define a range of risk. 25 DR. GLANTZ: Right. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 188 1 ACTING CHAIRMAN FROINES: We have no obligation 2 under the law to define a unit risk value. 3 DR. GLANTZ: Well, I understand. 4 ACTING CHAIRMAN FROINES: Let me finish. Let me 5 finish, because I just want to make a point. 6 One of the things that we all agree on here is 7 that further research is necessary, especially with respect 8 to the relationship between the nature of the diesel 9 particulate -- diesel exhaust with railroads and what people 10 are currently driving down the street today. 11 DR. FUCALORO: In their Mercedes. 12 ACTING CHAIRMAN FROINES: In their Mercedes. 13 And we know that we need to look to see is the 14 risk now similar to what we saw with coal miners or truckers 15 or railroad workers sometime back. 16 So that I think that there is some benefit to not 17 giving the South Coast Air Quality Management District a 18 bright line. And that part of that is what concerns me. 19 And that is that are we prepared in here to say 20 that we are sufficiently confident with what we are doing 21 that the bright line is what we really want to come out. 22 DR. BLANC: Stan, maybe I'm confused. 23 Dr. Witschi, maybe I misunderstood your 24 trepidation. 25 Is your trepidation only with giving a reasonable PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 189 1 best estimate, that you don't have any problem with saying 2 what we think the range of risk is? 3 I took your comment, I think, maybe too globally. 4 DR. FUCALORO: I took it the same way he did. I 5 thought you had a problem with the range also. 6 DR. WITSCHI: No. It's just this -- it's now a 7 bit difficult. 8 As I said, Allan Smith did the same thing, which I 9 think is much more plausible. 10 DR. BLANC: As a best estimate? 11 DR. WITSCHI: As a best estimate, because he does 12 not go through all the assumption about ramps, plateaus, 13 roofs and all those -- 14 DR. BLANC: Well, then that I do have -- I'm 15 sorry. I misunderstood you. I thought you had a much 16 deeper philosophical scientific global difficulty. 17 Well, then what I would suggest is that we, 18 instead of going through the exercise that we suggested 19 before of taking the geometric mean of all the estimates, 20 you just gives us the point estimate that would come from 21 assuming midlevel, 250 microgram per cubic meter value of 22 diesel and the 1.4 relative risk, and you're going to come 23 up with a value that's going to be 5.2 times 10 to the minus 24 4th, and I can -- I'd be very happy with that if you would 25 be happy with that. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 190 1 DR. GLANTZ: Would you be happy with that? 2 DR. WITSCHI: Yes. 3 DR. GLANTZ: I'm happy with that. 4 DR. FUCALORO: I'm ecstatic. 5 DR. GLANTZ: Okay. 6 DR. BLANC: That's fine. 7 DR. GLANTZ: Let's stop. 8 DR. BLANC: Let's stop right there. 9 ACTING CHAIRMAN FROINES: Wait, wait. We're not 10 done yet. We aren't done. 11 One, we haven't got to Dr. Kennedy yet. And he's 12 sitting there with a bombshell. 13 DR. GLANTZ: Wait. One point I want to just make, 14 at the risk of talking after we've reached consensus, I mean 15 the reason that I'm -- 16 ACTING CHAIRMAN FROINES: Stan, this is like 17 you're asking those people last week -- 18 DR. GLANTZ: Okay. I'll shut up. 19 ACTING CHAIRMAN FROINES: Can we go back to 20 another -- 21 DR. GLANTZ: Let the record record that the staff 22 are giggling. 23 ACTING CHAIRMAN FROINES: Peter has raised a 24 second substantive issue, which I think we now have to 25 address, and that is that he's raising a question about No. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 191 1 19, in which he's concerned about the -- why don't you 2 restate it, because I may state in incorrectly. 3 DR. WITSCHI: Well, this is again one of those 4 things which then can be looked at in different way. To 5 some people this calculating numbers are going to look like 6 real, to some people they're going to look like acceptable, 7 to others they are not going to look acceptable -- not 8 acceptable. 9 Whereas I think the evidence we have on diesel is 10 that clearly exposure of people to diesel is not acceptable. 11 DR. FUCALORO: I'm sorry? 12 DR. WITSCHI: Is not acceptable. Not just for the 13 cancer -- 14 ACTING CHAIRMAN FROINES: What I hear you saying 15 is that using this 200 to 3600 is based on a railroad worker 16 study of some time ago and it may not reflect the actual 17 risk in say Los Angeles today, so by putting these values in 18 may overstate the risk. Does that -- 19 DR. WITSCHI: Or understate the risk. 20 ACTING CHAIRMAN FROINES: Or understate. 21 The question is how can we best approach this 22 issue? 23 DR. WITSCHI: Why do we need -- that's really my 24 point, why do we need to convey to anybody that we have 25 to -- we are going to count bodies. And we know about PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 192 1 something is here, it's bad and something against it can be 2 done, regardless of how many bodies. 3 DR. FUCALORO: Your suggestion is to eliminate 19? 4 DR. WITSCHI: Yes. 5 ACTING CHAIRMAN FROINES: Stan. 6 DR. GLANTZ: Well -- 7 ACTING CHAIRMAN FROINES: I have a feeling that 8 Peter is agreeing with that. Or are you just acknowledging? 9 DR. KENNEDY: I'll say my piece. No, I agree. 10 DR. GLANTZ: I just consulted with the staff, and 11 I need to slightly amend my agreement with the previous 12 point, after prefacing it with I'm willing to throw away 19 13 to get 18 the way I want it, because I agree with Hanspeter, 14 I don't think it's the point 19 is particularly necessary. 15 The problem I have with just basing it on Allan 16 Smith's number, that gives us the absolute bottom of the 17 range we've got from all the other studies. And I think 18 that, while I agree with you, in fact I was talking to 19 Melanie at the break, that after he does the back of the 20 envelope calculation that comes out very close to what they 21 did after years of analysis, I think that I would feel more 22 comfortable with something that's closer to the middle of 23 the plausible range, rather than at the bottom of it. 24 I was under the impression the Smith number came 25 out closer to the middle. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 193 1 ACTING CHAIRMAN FROINES: Oh, come on. 2 DR. FUCALORO: It comes out to 5 times 10 to the 3 minus 4. 4 ACTING CHAIRMAN FROINES: These numbers -- 5 DR. GLANTZ: 5 times 10 to the minus 4. 6 DR. FUCALORO: I better verify that. 7 DR. GLANTZ: If it comes out 5 times 10 to the 8 minus 4, I'm happy. I just -- 9 ACTING CHAIRMAN FROINES: None of it's correct 10 anyway. 11 DR. GLANTZ: Well, don't say that. 12 ACTING CHAIRMAN FROINES: It's a risk assessment. 13 DR. GLANTZ: I know, but, thanks, you just got 14 yourself sued. 15 ACTING CHAIRMAN FROINES: None of this is real. 16 DR. ALEXEEFF: Let me just make a -- 17 MS. SHIROMA: None of it is precise. 18 DR. ALEXEEFF: If I can just make a comment. 19 If we rounded, if we used 250 micrograms per cubic 20 meter as was suggested, all we have to do is in his -- in 21 Dr. Smith's equation, is substitute 250 for 67, so you can 22 see if you did that it's divisible by about four. So the 23 number, if you round to one digit, would be 1 times 10 to 24 the minus 4, just so you know what the number is, which is 25 at the bottom of our range. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 194 1 ACTING CHAIRMAN FROINES: Well, let's go with 2 that. 3 DR. WITSCHI: Well, you know, that's we've gone 4 through risk hazard identification, we have done some risk 5 management, what about risk communication. I mean, the 6 coming up with something rather than giving a risk -- let me 7 finish. To like the calculation is the potency factor and 8 so on, but Allan Smith essentially says look in people who 9 are exposed to rather high amounts of diesel, so and so much 10 was added to their, what they would had gotten anyway in 11 lung cancer, and we should have learned a lesson from there, 12 and if we do some very simple calculations, then if what 13 people are exposed to on the street, so and so much is going 14 to add to their burden. And that's much more easy to 15 understand than any -- 16 DR. GLANTZ: Right. But the difference is that I 17 think that we have a lot -- we do have a lot more 18 information than just that one calculation. 19 And I mean you have Kyle Steenland's work, which 20 is -- he's very very meticulous. It came out around seven 21 or eight. 22 And I just think we should pick something that's 23 near the middle, and not at the bottom. I mean, at one 24 level to me we're talking about 10 to the minus 3, to 10 to 25 the minus 4, and that's a fairly narrow range. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 195 1 But I just think based on having spent a lot of 2 time studying this and working and trying to understand the 3 differences between all these different competing analyses, 4 and why different people got different numbers, and reading 5 all of these studies, I think the bottom of the plausible 6 range, which is lower than the real number is likely to be, 7 and I think the top of the plausible range is higher than 8 the real number is likely to be. And I think that if we 9 just specify that range, then what's going to end up 10 happening is that certain people are going to come in and 11 argue for the low end and other people are going to argue 12 for the upper end, based largely not on any grand 13 philosophical or scientific reasoning, but their political 14 positions. 15 What I'd like to see us say is that we're giving 16 you a range, but we think the most reasonable number is 17 something in the middle, because I think if you look at all 18 the studies and if look at all the different -- 19 ACTING CHAIRMAN FROINES: George -- 20 DR. GLANTZ: Of the two Garshick studies under a 21 wide variety of assumptions, they tend to cluster in the 22 middle. And I think we want to draw attention to that. 23 And so I just think to say we're going to rely on 24 one back-of-the-envelope calculation that gives you the 25 bottom end of the risk, even though I'm very sympathetic PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 196 1 with the calculation, I think it really strengthens the 2 whole rest of the argument, I just think we should be 3 picking a number somewhere in the middle. 4 If you don't want to do a geometric mean, I mean 5 the four number I came up with was from staring at the 6 graph, that highly quantitative method, and George, it 7 turned out, got the same thing. 8 DR. BLANC: Let me make -- I was taking an 9 arithmetic mean between five and 500, which is probably also 10 too primitive, so if you take the mean value that Allan 11 Smith took, which was 67, so it's not the arithmetic mean 12 between this low of the bracket of five and the top of 500, 13 then I think the value that was arrived at was 3 times 10 to 14 the minus 4th, which is very close to your four times -- 15 DR. GLANTZ: I would be satisfied with that. 16 DR. FRIEDMAN: How about, would you be satisfied 17 with not giving a number, but just saying we think that the 18 true risk is probably somewhere in the middle? 19 DR. GLANTZ: No. I think we need to give them a 20 number that we think is reasonable. 21 DR. BLANC: I think 3 times 10 to the minus 4th, 22 which is the number -- 23 DR. GLANTZ: I'm happy with that. 24 DR. BLANC: -- based on I guess 67 micrograms per 25 meter. Do I have that number right, people from -- PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 197 1 DR. MARTY: Allan Smith's was 5 times 10 to the 2 minus 4, based on 67 micrograms per -- 3 DR. FUCALORO: Microgram per meter cubed, right. 4 DR. BLANC: And he arrived at 67 as a kind of mean 5 value based on -- where did 67 come from? 6 DR. ALEXEEFF: The 67 actually is basing it on the 7 railroad worker information, using the Woskie data where you 8 have a background level of -- well, approximately 80 9 something, 83, it's subtracting out the other -- the 10 non-diesel background and you come to 67. 11 DR. BLANC: Does that seem like a reasonable mean 12 for all of the pooled various occupations that we looked at, 13 some of which were clearly much higher than that and some of 14 which were lower than that, in your -- 15 DR. FUCALORO: It only has to apply -- it needs to 16 apply to the finding that there's a 40 percent increase in 17 background lung cancers. So to use other data you'd have to 18 look at what that increases. So he's using .4 over 20, 19 assuming that that's increase from 1 over 20, which is the 20 incidence of lung cancer in the general population; right? 21 So that's an extra .4, and that .4 over 20 is 22 equal to the risk factor times the exposure, and if the 23 exposure is 67, .4 out of 20 increase, then you come up with 24 this number that you find acceptable. 25 DR. GLANTZ: Is 3 -- that's fine with me. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 198 1 ACTING CHAIRMAN FROINES: I want to stop 2 everybody's discussion, and I want -- I want one of the four 3 of you, or whoever, to express to me the justification and 4 the basis for the number that you're now proposing. 5 And it has to be said very clearly, because what 6 you're saying to every citizen of California is that through 7 a rigorous scientific process we have established what we 8 consider to be the best value for diesel exhaust risk with 9 respect to lung cancer. 10 DR. GLANTZ: Okay. Let me, as the first -- 11 ACTING CHAIRMAN FROINES: Go on the record -- 12 DR. GLANTZ: I'll try to express it on the record. 13 Okay. 14 The way that I would prefer to -- I think that we, 15 having spent years working at this, going to multiple 16 workshops and spending more time than I care to add up 17 reading all of this stuff, are the best-positioned people to 18 make a recommendation of what a reasonable number would be. 19 I did not say it's the best number, although I 20 actually think it is. I'm happy to use the word reasonable. 21 The range of risk estimates that have come out of 22 this entire exercise, whether you look at the Garshick data, 23 the two Garshick data sets, under a variety of assumptions 24 of exposure patterns, which are reasonable, if you look at 25 the Allan Smith back-of-the-envelope calculation, if you PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 199 1 look at the Steenland studies and the other new studies, the 2 results to me are remarkably consistent, yielding risk 3 estimates in the range of 10 to the minus 4, to 10 to the 4 minus 3. 5 I think, however, that it is unlikely that we are 6 in either of the upper or lower end of that range, and that 7 if you look at figure -- at the figure in the report, which 8 shows the effects of the different exposure models that are 9 used, you'll see that most of them cluster around the middle 10 of that range. 11 And so to me the procedure which I think is the 12 best one to use is the one that got suggested of computing 13 the geometric mean of these different estimates, because I 14 think that's the one which is most likely to come out near 15 what the actual number really is. 16 Now, if all the mathematical gyrations which are 17 involved in doing that bother Hanspeter sufficiently that he 18 wants to stay with a simpler thing, if those come out about 19 the same, I'm not going to make an issue of it because I 20 don't think the difference between three and four or four 21 and five isn't that much to me. 22 My concern is that we not come in with a number 23 that's at the bottom of the range, because I think that's 24 unlikely to be the correct number. 25 ACTING CHAIRMAN FROINES: Let me stop. You PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 200 1 make -- you're talking to The Los Angeles Times, The San 2 Francisco Chronicle, you're explaining why you have selected 3 this value, and in two paragraphs why this is the best 4 value. 5 DR. GLANTZ: Want me to try it again? 6 ACTING CHAIRMAN FROINES: If you can't do it, 7 somebody else should, but it has to be clear. 8 DR. GLANTZ: Let me try one more time, John. 9 And that is that there is -- there is a certain 10 amount of uncertainty associated with these different risk 11 estimates, due to all the stuff we've been discussing 12 obsessively. 13 And when you look at the range of risk estimates 14 that you get, some of that uncertainty is going to bias the 15 estimate up and some of it's going to bias the estimate 16 down. 17 And I think the most reasonable estimate is in the 18 middle. And that's why I'm suggesting we say that, not that 19 it's at the bottom or the top. And to me the middle is 20 around 4 times 10 to the minus 4. 21 That's where I came up with that number. 22 ACTING CHAIRMAN FROINES: Peter. 23 DR. GLANTZ: So that's how I would explain it to 24 The LA Times, who is sitting back there. 25 ACTING CHAIRMAN FROINES: Can you speak to that? PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 201 1 DR. WITSCHI: The way I see it, I might be naive 2 with that one, but what you're looking at for coming in the 3 ranges four or five data set bases, the two Garshick 4 studies, the Steenland studies -- 5 ACTING CHAIRMAN FROINES: Meta-analysis. 6 DR. GLANTZ: The meta-analysis. 7 DR. WITSCHI: Well, yes, and those -- 8 DR. GLANTZ: I don't think that's what we just -- 9 I'm sorry. 10 DR. WITSCHI: Well, the way I see the other one, 11 Allan Smith's estimate, is based on very broad data sets, 30 12 or so studies, so the database is much broader than yours, 13 the 30 to 40, and fewer assumptions. That's how I would 14 justify it, we came to this number. It's a broader database 15 and fewer assumptions. 16 ACTING CHAIRMAN FROINES: George, what are the two 17 numbers? 18 DR. ALEXEEFF: Okay. The number varies depending 19 upon -- 20 ACTING CHAIRMAN FROINES: No, I didn't ask you for 21 the number varies -- I asked you for -- 22 DR. ALEXEEFF: Five or one. 23 ACTING CHAIRMAN FROINES: What? 24 DR. ALEXEEFF: You asked what the two numbers 25 were. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 202 1 ACTING CHAIRMAN FROINES: His number is what? 2 DR. ALEXEEFF: Five. 3 ACTING CHAIRMAN FROINES: 5 times 10 to the minus 4 4. 5 DR. ALEXEEFF: Yeah. I'm sorry. Are you talking 6 about the geometric mean number? 7 ACTING CHAIRMAN FROINES: I'm talking about the 8 number that he just said is the best number that -- 9 DR. ALEXEEFF: We chose the geometric mean, we 10 haven't done the calculation yet, but it would be about 11 five. 12 ACTING CHAIRMAN FROINES: 5 times 10 to the minus 13 4. 14 What is Peter's number? 15 DR. ALEXEEFF: Hanspeter would be 5. 16 ACTING CHAIRMAN FROINES: Unless I'm mistaken -- 17 DR. ALEXEEFF: If we use Allan Smith's exact 18 calculations, it would be five. If we use 250, it would end 19 up being one. Okay. That's -- 20 DR. WITSCHI: I could live with two things. One 21 is with Allan Smith's estimate, and the other one by some 22 addendum that a point estimate is not good enough, you 23 really have to consider ranges. 24 DR. GLANTZ: We have given them the range, too. 25 I'm not saying -- wait, so you're saying if we did Allan PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 203 1 Smith's just the way he did it, it would also be five? 2 DR. ALEXEEFF: Yes. 3 DR. GLANTZ: Then there's nothing to disagree 4 about. Then we agree, it should be five. Because whether 5 you do it the simple-minded way or the unsimple-minded way, 6 you get the same answer, which means it's probably right. 7 ACTING CHAIRMAN FROINES: Here's what we're going 8 to do. 9 You two are going to work -- you two -- excuse me. 10 You two are going to work with Hans and Stan and the four of 11 you are going to come up with a number, and the two of them 12 are going to write the specific language that will go in 13 here to go with that language. 14 DR. GLANTZ: No. 15 ACTING CHAIRMAN FROINES: No, no, no. We're going 16 to try and get this done. 17 DR. GLANTZ: You mean right now? Okay. 18 ACTING CHAIRMAN FROINES: We're not going to 19 necessarily do it right now. We can agree that the number 20 is going to be in the middle and we'll have to agree that 21 the language will get -- 22 DR. GLANTZ: You're making this too complicated. 23 I think we just agreed. 24 ACTING CHAIRMAN FROINES: No, no. But you don't 25 understand is I'm trying to get this process through, one. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 204 1 Secondly, I'm trying to get a justification that 2 will go to the Air Resources Board that when it's written 3 down they will understand it and say, yes, that makes sense 4 to me. 5 DR. GLANTZ: But let me try and tell -- 6 ACTING CHAIRMAN FROINES: I don't want you to try 7 to say it anymore. 8 DR. GLANTZ: John, you're making it -- 9 ACTING CHAIRMAN FROINES: I want you to sit down 10 and write it. 11 DR. GLANTZ: Well, no. I think that we've said 12 it. There's two different ways you can do this. 13 One way is to take the Allan Smith simple 14 approach, which with his numbers which leads you to an 15 estimate of 5 times 10 to minus 4, right? 16 ACTING CHAIRMAN FROINES: Right. 17 DR. GLANTZ: Just listen to me. 18 ACTING CHAIRMAN FROINES: Stan, I've heard this 19 twice. You're missing the point. 20 DR. GLANTZ: No, I'm not missing the point. 21 You're missing the point. 22 The other thing is that you can go through this 23 other process that was described, which is more involved, 24 and gives you the same answer. So it doesn't matter. 25 MS. SHIROMA: Dr. Glantz, I think that what the PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 205 1 chair is referring to is at times as we've dealt with 2 substances, the chair directs a subcommittee to come up with 3 the exact language over the next few days type of thing, 4 that is then passed around to the panel members before the 5 chair signs it. I think that's all he's -- 6 DR. GLANTZ: I don't think we should put this in 7 the findings. It's too technical. I think if we want to 8 add something to the report explaining this that would be 9 okay. 10 ACTING CHAIRMAN FROINES: Excuse me, but the issue 11 of the quantitative risk assessment has been the most 12 debated element of this entire process. If you're going to 13 put in a range of risk and a unit risk value, you're going 14 to say as part of that, what the justification of it was. 15 Otherwise, I'm not going to send it forward, 16 because it has to be stated clearly to the Air Resources 17 Board the basis of our decision. 18 DR. GLANTZ: But, you see, I think -- 19 ACTING CHAIRMAN FROINES: Stan, don't argue with 20 me. That's the way it's going to be. It's got to be 21 written in a coherent, clear way, so that it is effectively 22 justified for the body politic and for the Air Resources 23 Board in particular. 24 I'm sorry. That's the way it has to be. 25 Now, you can go sit out in the hall now and the PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 206 1 two of you can write it, but we're going to get it written 2 before this thing goes forward. 3 DR. GLANTZ: We'll do that now, because I think we 4 need to do that before we leave. We'll go write it. 5 ACTING CHAIRMAN FROINES: George has the numbers, 6 I think. 7 I want everybody to understand why I sound a 8 little bit dogmatic. 9 DR. BLANC: No, I think -- 10 DR. BYUS: You're absolutely correct. 11 DR. FRIEDMAN: We understand. 12 DR. BLANC: You don't have to convince us. 13 DR. KENNEDY: Say no more. 14 DR. BLANC: I think that we're trying to preserve 15 consensus in a difficult situation where people hold 16 different points of view, and it's challenging because some 17 of those points of view are so fundamentally different than 18 the process mandates that it does provide an inherent 19 conflict. 20 ACTING CHAIRMAN FROINES: Well, I just -- the 21 other thing is I would hate to see the ARB sued because an 22 inadequate justification for a selection of a value was 23 made. 24 DR. BLANC: No, I think you're right. You don't 25 have to justify yourself to us. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 207 1 ACTING CHAIRMAN FROINES: You have to tell people 2 why you do things. 3 DR. BLANC: While they're out of the room, 4 Dr. Kennedy, I think you had supported the view, and Stan 5 before he left and Hanspeter had both seemed to be saying 6 that they could live with point 19 coming out. Is that -- 7 did anybody object to point 19 coming out? 8 ACTING CHAIRMAN FROINES: I think given the 9 changes in diesel exhaust that are occurring, that makes 10 perfect sense. 11 DR. BLANC: So I think we should move forward and 12 just hear from Dr. Kennedy if there are other issues he 13 wants to bring up. 14 DR. KENNEDY: I have very few. They've 15 essentially all been discussed. 16 I am on this board representing probably a 17 position closer to every man than any of the rest of you. 18 I'm a clinician. 19 I don't deal with the sorts of calculations and 20 perspectives that you do, and I frankly found a lot of the 21 mental gymnastics that were involved in model development 22 and manipulation to be somewhat baffling. 23 And whether it be a function of perspective or 24 simply knowledge based, I am more comfortable in this 25 simpler method of arriving at this information. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 208 1 Because of it, I think also that section 19 is 2 window dressing. It is not really essential to the 3 information that you're trying to convey and I think it just 4 has no value. 5 With a bit of background in biology, I had some 6 concerns about the mixing of animal and human epidemiologic 7 data, and that's been taken care of, I think, with good 8 compulsive concern for detail. 9 On all other fronts, my only other question 10 relates specifically to section 15 in the middle of the 11 second sentence, sister chromatid exchange in rodents and 12 human cells in vitro. Are the rodent data in vitro as well? 13 ACTING CHAIRMAN FROINES: George? 14 DR. BUDROE: John Budroe, OEHHA. 15 Yes. Both. 16 DR. KENNEDY: Both, yes. Okay. Then I'm happy. 17 DR. BLANC: If you're happy, I'm happy. 18 DR. FUCALORO: Well, go ahead. 19 DR. BLANC: Are you sitting in for John? 20 DR. FUCALORO: Yes. 21 DR. BLANC: Why don't you suggest we take a 22 ten-minute break. 23 DR. FUCALORO: I'm suggesting we take a ten-minute 24 break. 25 (Thereupon a short recess was taken.) PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 209 1 ACTING CHAIRMAN FROINES: Do we have everybody in 2 the room? I want Peter to finish. 3 Peter, I appreciate your comments. 4 All right. I want to wait for Friedman if he's 5 here. 6 DR. KENNEDY: For the record, can I add one 7 additional small statement and that was I am grateful that 8 we have the addition of two additional two studies to expand 9 the database. I think that -- again, as someone who is 10 sitting on the periphery of all this, I'm much more 11 comfortable in our deliberations with the ability to see 12 different perspectives coming up with the same answer. 13 And I think great credit goes to the folk at OEHHA 14 for laboring so long and hard with the work, the information 15 they had. 16 ACTING CHAIRMAN FROINES: Actually I labored to 17 get those two, but that's okay. 18 DR. GLANTZ: Here's what he wrote. 19 And this sort of actually gets -- 20 ACTING CHAIRMAN FROINES: Just read it. 21 DR. GLANTZ: The point that Peter just made that 22 you get -- the fact that you get to the same place by such 23 different pathways is, I think, important. 24 Okay. Here is what we wrote. 25 After considering the results of the meta-analysis PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 210 1 of all -- I should say all human studies probably -- as well 2 as the detailed analysis of the studies of railroad workers, 3 the SRP believes that 3 times 10 to the minus 4 is a 4 reasonable estimate of the unit risk expressed in terms of 5 micrograms per cubic meter of diesel exhaust particulates or 6 their surrogates. 7 DR. FUCALORO: To the minus 1? 8 DR. GLANTZ: 3 times 10 -- 9 DR. FUCALORO: Micrograms to cubic meter, quantity 10 to the minus 1. 11 DR. GLANTZ: Right. 12 DR. WITSCHI: We can even say instead of believe, 13 came to the conclusion. 14 DR. GLANTZ: Concludes. All right. 15 ACTING CHAIRMAN FROINES: Now, what was the basis 16 for that conclusion? 17 DR. GLANTZ: The basis for the conclusion was what 18 Peter Kennedy said, that when you come at this through two 19 totally disparate approaches you end up with almost 20 identically the same number. 21 ACTING CHAIRMAN FROINES: Write that down, because 22 you can come to a conclusion, but then you tell the audience 23 how you came to the conclusion. 24 DR. GLANTZ: We did. We considered the results of 25 the meta-analysis of all the studies, which is one approach, PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 211 1 and the other approach was the detailed analysis of the 2 railroad workers, which is the second approach. 3 ACTING CHAIRMAN FROINES: And then add Peter's 4 sentence then. 5 DR. BLANC: How about this as that sentence. 6 Thus, this unit risk value reflects two separate approaches 7 yielding similar values. 8 DR. GLANTZ: That's fine. 9 DR. FRIEDMAN: I thought that you said before that 10 it was five. How did you get three? 11 DR. ALEXEEFF: It's actually Dr. Fucaloro 12 explained why it's three and not five. Five would be the 13 risk for the background level of 1.5 micrograms per cubic 14 meter. 15 DR. FUCALORO: No, no, no, no. Five is the five 16 additional cancer cases per -- four and a half -- per 17 10,000. 18 DR. ALEXEEFF: Five is the cancer burden. That is 19 to say when you take into account the background level, but 20 the unit risk value he calculates is three. 21 DR. FUCALORO: Three micrograms per cubic meter to 22 the minus one power. 23 ACTING CHAIRMAN FROINES: Thank you, George. 24 Let me say that we now have a -- how are we 25 describing it? As a reasonable unit risk value, which is PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 212 1 justified on the basis of the evaluation of the data, 2 understanding that there are different data sources and yet 3 when looking at all those data sources this summation 4 represents the best value. 5 Is that -- 6 DR. GLANTZ: We're happy with that. 7 ACTING CHAIRMAN FROINES: I'm trying to make sure 8 the record indicates that this is a best value which we have 9 scientific -- what's the word -- scientific confidence in. 10 DR. GLANTZ: Yes. 11 ACTING CHAIRMAN FROINES: And it's meaningful in 12 that regard. 13 DR. GLANTZ: Yes. 14 ACTING CHAIRMAN FROINES: Everybody agrees with 15 that? 16 So around the room, there's no dissent on that 17 point of view? 18 And George or Genevieve are going to take all 19 that's been said today and produce a new draft findings, 20 which will be circulated to the panel for final final 21 agreement; correct? 22 MS. SHIROMA: Yes, that's correct. Before you 23 sign the final. 24 ACTING CHAIRMAN FROINES: Right. I'm trying to be 25 very clear, because simply because we make offhand comments PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 213 1 about risk assessment values, I want to make sure that we 2 all believe in what has been done here. 3 And I think the record that our lawyer friends 4 will now feel confident that we haven't created uncertainty 5 in the findings of the panel. 6 DR. GLANTZ: Paul, why don't you read me the 7 sentence, just to be sure, why don't you read me your 8 sentence, let me write it down and let me reread the whole 9 thing one more time. 10 DR. BLANC: Thus, this unit risk value reflects 11 two separate approaches. 12 DR. GLANTZ: Just a second. This unit risk 13 value -- 14 DR. BLANC: Reflects two separate approaches 15 yielding similar values. 16 DR. GLANTZ: Let me just for the record read this 17 one last time, make sure everyone agrees with it. 18 After controlling -- or after considering the 19 results of the meta-analysis of all human studies, as well 20 as the detailed analysis of the railroad workers, the SRP 21 concludes that 3 times 10 to the minus 4 per microgram per 22 cubic meter is -- should I say the best estimate? Because 23 that's what people are now saying. 24 DR. BLANC: No. Reasonable. 25 DR. GLANTZ: Is a reasonable estimate of the unit PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 214 1 risk expressed in terms of diesel particulates or their 2 surrogates. Thus, this unit risk -- or this unit risk -- 3 thus, this unit risk value reflects two separate approaches, 4 which yields similar values. 5 ACTING CHAIRMAN FROINES: Great. That's great. 6 DR. GLANTZ: Who should I give that to? 7 ACTING CHAIRMAN FROINES: Give that to Genevieve. 8 That's really good work, gang. That's really good 9 work. 10 And we sent the two people who I would never have 11 predicted would have come back that fast to do it. 12 Friedman and Blanc be back in ten seconds, but you 13 guys. 14 Now, George keeps trying to get in here. 15 DR. ALEXEEFF: Yes. If I could make one proposed 16 modification or clarification. 17 The meta-analysis did not include all of the human 18 studies. There were exclusion criteria for selecting those 19 studies which -- 20 ACTING CHAIRMAN FROINES: Can't we put that as a 21 footnote? 22 DR. ALEXEEFF: We can just take out the word all, 23 because it's the meta-analysis of all humans studies, but 24 it's a meta-analysis of human studies. 25 DR. FUCALORO: What you're referring to is a PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 215 1 specific meta-analysis that was done in the report so it's 2 not a vague term. 3 ACTING CHAIRMAN FROINES: Okay. Now, gentlemen -- 4 DR. GLANTZ: What about No. 19? 5 DR. BLANC: We got rid of that. 6 DR. GLANTZ: Okay. 7 ACTING CHAIRMAN FROINES: Now, the following is a 8 proposed addition to our findings, and I'm not sure the 9 exact number, but it will be towards the end, maybe 22. 10 It reads as follows. 11 The panel has reviewed the report, "Proposed 12 Identification of Diesel Exhaust as a Toxic Air Contaminant 13 Report," as well as the scientific procedures and methods 14 used to support the data, the data itself and the 15 conclusions and assessments on which the report is based. 16 The panel finds that the report is based on sound scientific 17 knowledge, methods and practices. 18 That's simply is a requirement that says that the 19 panel is acknowledging the State has met the obligation 20 under the law. 21 DR. GLANTZ: So moved. 22 ACTING CHAIRMAN FROINES: So moved. 23 DR. WITSCHI: Second. 24 ACTING CHAIRMAN FROINES: Okay. Secondly, No. 20, 25 we have based on the available scientific information a PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 216 1 level of diesel exhaust exposure below which no carcinogenic 2 effects are anticipated cannot be identified. 3 DR. WITSCHI: I know we have used the sentence 4 before, but strictly speaking the scientific method never 5 can show the evidence that something is not going to happen. 6 DR. FUCALORO: Had not been identified, is that 7 better? 8 ACTING CHAIRMAN FROINES: Shall we say has not 9 been identified? 10 DR. FUCALORO: I don't know if it's plural. It 11 has not been identified. 12 ACTING CHAIRMAN FROINES: Has not. And we reserve 13 the right to -- 14 DR. FUCALORO: To find it. 15 ACTING CHAIRMAN FROINES: To find it. 16 Based on available scientific evidence as well as 17 the results of the risk assessment, we conclude that diesel 18 exhaust be identified as a toxic air contaminant. 19 Any no votes at this point we throw that person 20 out. 21 DR. GLANTZ: Actually -- 22 DR. BLANC: Oh, please. 23 ACTING CHAIRMAN FROINES: And that's it. 24 DR. GLANTZ: I move we accept the findings. 25 DR. FUCALORO: Before we do that, I really need to PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 217 1 mention something that Jim Seiber wrote, and just be a 2 consideration. I actually think we've covered much of this, 3 so let's see. I haven't read it since we've had this 4 discussion. 5 He writes although the accumulated evidence 6 indicates that diesel exhaust is carcinogenic, there is much 7 uncertainty over the unit risk or potency factor for cancer 8 in humans due to exposure to diesel exhaust. 9 In part this is due to species differences and 10 effects in experimental animals, and in part due to the lack 11 of measured exposure data in diesel locomotive work in 12 epidemiological study. 13 SRP does not support selection of either a single 14 unit -- he does not support a selection of either single 15 unit risk factor or definitive range based upon available 16 data. SRP rather supports a continuing search for 17 scientific basis for developing a single factor with 18 definitive range. A search should focus on diesel exhaust 19 as emitted from diesel engines in current use using diesel 20 fuels in current use. 21 I think the last thing we are going to do, but 22 we've grappled with those other issues. 23 ACTING CHAIRMAN FROINES: I don't think we should 24 take up most of that, because we've already dealt with it. 25 But I would agree that we could put a sentence in PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 218 1 that says that given the difficult issues associated with 2 diesel exhaust that we support and -- 3 DR. FUCALORO: Encourage. 4 ACTING CHAIRMAN FROINES: Encourage additional 5 research. 6 DR. GLANTZ: We've already said that. It's in 7 there already. 8 ACTING CHAIRMAN FROINES: Where? 9 DR. FUCALORO: We did it. 10 DR. GLANTZ: It's in there somewhere. 11 It's in No. 7. 12 ACTING CHAIRMAN FROINES: Not in my No. 7. 13 DR. FUCALORO: No. 8. 14 ACTING CHAIRMAN FROINES: It's now become No. 8. 15 But I still don't think that's enough. I think we 16 should have a concluding statement that says further 17 research on diesel exhaust exposure issues and health 18 effects and risk assessment would be -- should be 19 encouraged. 20 DR. BLANC: I would just -- I would not do that, 21 actually. 22 DR. GLANTZ: I agree. 23 DR. BLANC: I would not do that because I think 24 that placing that statement at the end unnecessarily weakens 25 the conclusion, which could come back to be negatively PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 219 1 exploited in ways that you would not intend from such a 2 statement. So I would simply leave well enough alone. 3 I don't think you have any reason to doubt that 4 there's going to be a lot of interest in further research. 5 ACTING CHAIRMAN FROINES: I think -- I disagree on 6 this one with you guys. I think that further research is 7 required and it's important. 8 DR. BLANC: I don't disagree with that. I'm just 9 purely arguing on a tactical, strategic basis, not because I 10 disagree with that. 11 DR. GLANTZ: Our job is not to outline the 12 research agenda. Further research is always required on 13 everything. 14 And I agree. I think that for -- I think that of 15 all the reports that we have looked at on this committee, 16 this is the strongest, except, of course, maybe the one on 17 secondhand smoke, and I think the evidence -- I had to get 18 that in. 19 And I think the statement that he's proposed, that 20 Seiber proposed, really makes it sound like it's weaker than 21 it is. And I mean there's lot of issues that have been 22 brought up in the discussion today that need further 23 research and I think that that speaks for itself. 24 But I don't think that -- I think to put that in 25 as a formal finding at the end like that will make it sound PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 220 1 like there's a lot more uncertainty here than there is. 2 DR. FUCALORO: In fact we have put it in, and you 3 put in No. 7, but look at the last sentence in the old No. 4 10, what is that, No. 11 now. And it says further research 5 would be helpful to quantify the amounts of specific 6 compounds emitted from a variety of engine technologies, 7 operating cycles and fuel to better characterize any 8 differences between old and new fuels and technologies. And 9 I assume old and new refers to both fuels. 10 DR. BLANC: We also said in the non-cancer health 11 that we added a statement that said as new data emerge that 12 this should be -- 13 ACTING CHAIRMAN FROINES: I don't have that, 14 because I don't have -- 15 DR. BLANC: It's now item 15, the old item 14, 16 that we added the sentence that should be recognized that 17 this REL may need to be lowered further as quantitative -- 18 ACTING CHAIRMAN FROINES: I think that there 19 are -- I believe that there are significant research around 20 the mechanism of carcinogenicity, how one addresses 21 interactive effects and complex mixtures. We have never 22 said a word about dermal absorption in this particular 23 document. We do not know the role of nitro-PAHs. 24 And I can give you a list of hundred things that 25 are important. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 221 1 I think that research is important -- 2 DR. BLANC: I'll compromise this far. I don't 3 object to putting in such a sentence. I don't think it 4 should be the last sentence of the document, so if you can 5 figure out a place -- 6 ACTING CHAIRMAN FROINES: George and Genevieve, 7 George and Melanie, as you guys are working to finalize this 8 to come back to us, find a place to put a sentence in about 9 the need for additional health effects related to research. 10 And we won't try and do it right this minute. 11 And we'll circulate it. 12 But I frankly think that this -- that there are so 13 many very deep scientific issues, some of which have to do 14 with the fact, for example, I think Mauderly is not entirely 15 correct in the way he's interpreting his animal data, and 16 there are a number of issues that are -- that may show 17 diesel's less of a carcinogen and some may show it more, but 18 I think those issues need to be resolved, because there are 19 immense industrial significance to this use of diesel in the 20 country, and I think we have to take that seriously. 21 So I really believe that a call to recognize that 22 research has to go on is an important and I think this panel 23 should be able to say that without feeling as though we were 24 undercutting ourselves, or causing more insecurity about our 25 findings, because I think this is quite -- this is one of PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 222 1 the best discussions of the science I've ever had in the 15 2 years I've been on this committee. 3 So I think it's a great effort, but I think we do 4 need to recommend that further actions go forward. 5 DR. BLANC: One other small question. 6 The very end of the finding, are you still acting 7 chair? When do you just become chair? 8 ACTING CHAIRMAN FROINES: I don't have anything to 9 do with that. 10 DR. BLANC: That has to come from the ARB? 11 ACTING CHAIRMAN FROINES: Yeah. Maybe I've been 12 here long enough and I can retire. 13 DR. GLANTZ: I'd like to move that we accept the 14 findings as amended. 15 DR. BLANC: I second that. 16 ACTING CHAIRMAN FROINES: I want to congratulate 17 the staff of the two agencies. 18 DR. BLANC: I think, can the record just reflect 19 that we've reached consensus? 20 DR. GLANTZ: Let's vote. 21 ACTING CHAIRMAN FROINES: We'll take a vote. 22 Sorry, I thought I took that as being a given almost. 23 So that the accepting of the findings vote, all 24 those in favor raise their hand for aye. 25 (Showing of hands.) PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 223 1 DR. GLANTZ: It's unanimous. 2 Could I also move that we accept the reports as 3 amended. 4 DR. BLANC: Second. 5 ACTING CHAIRMAN FROINES: All those in favor, say 6 aye. 7 (Ayes.) 8 ACTING CHAIRMAN FROINES: Now can I say thank you? 9 DR. BYUS: Say nice things. 10 ACTING CHAIRMAN FROINES: I think this has been 11 the most extraordinary effort that I've ever viewed in 12 federal or state or local government. I think that the 13 intellectual effort, the perseverance, the tenaciousness is 14 unparalleled. And I think we owe a debt of gratitude, and I 15 think the public of this state owes a debt of gratitude to 16 the people in this room, because I think this has been a 17 real difficult effort, and I think we've come through it and 18 I think we've come through it very very well. 19 And I'm really pleased at the consensus of this 20 committee. I think this committee worked very hard and very 21 well today and at the last meetings, and I think we owe a 22 pat on the back for ourselves, as well as the pat on the 23 back to the staff who have been working with us. 24 So thank you very much. We've made a big step 25 today, I think. And we should all take credit for it. PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 224 1 Good luck at the next stage. 2 MR. OLIVER: Thank you, Chairman Froines. 3 Please let the record reflect that the second 4 motion to adopt the report was carried by unanimous vote of 5 the panel. 6 DR. BLANC: So does you saying Chairman Froines, 7 instead of Acting Chairman Froines, reflect any kind of 8 change in status? 9 MR. OLIVER: Don't worry, it's not correct. It's 10 only a statement from a lawyer. 11 DR. GLANTZ: Are we done? 12 ACTING CHAIRMAN FROINES: We're done. We did it. 13 (Thereupon the meeting was adjourned 14 at 4:25 p.m.) 15 16 17 18 19 20 21 22 23 24 25 PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345 225 1 CERTIFICATE OF SHORTHAND REPORTER 2 3 I, JANET H. NICOL, a Certified Shorthand Reporter 4 of the State of California, do hereby certify that I am a 5 disinterested person herein; that I reported the foregoing 6 meeting in shorthand writing; that I thereafter caused my 7 shorthand writing to be transcribed into typewriting. 8 I further certify that I am not of counsel or 9 attorney for any of the parties to said meeting, or in any 10 way interested in the outcome of said meeting. 11 IN WITNESS WHEREOF, I have hereunto set my hand 12 this 29th day of April 1998. 13 14 15 16 Janet H. Nicol 17 Certified Shorthand Reporter License Number 9764 18 19 20 21 22 23 24 25 PETERS SHORTHAND REPORTING CORPORATION (916) 362-2345