Vandenberg, John

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Pace Environmental Law ReviewVolume 16Issue 1 Winter 1998 Article 5January 1998Scientific Research for Ozone and Fine ParticulateMatterJohn VandenbergFollow this and additional works at: http://digitalcommons.pace.edu/pelrThis Article is brought to you for free and open access by the School of Law at DigitalCommons@Pace. It has been accepted for inclusion in PaceEnvironmental Law Review by an authorized administrator of DigitalCommons@Pace. For more information, please contact cpittson@law.pace.edu.Recommended CitationJohn Vandenberg, Scientific Research for Ozone and Fine Particulate Matter, 16 Pace Envtl. L. Rev. 53(1998)Available at: http://digitalcommons.pace.edu/pelr/vol16/iss1/5Scientific Research for Ozone andFine Particulate MatterDR. JOHN VANDENBERG*It is my pleasure today to provide a brief overview ofsome of EPA's research program activities, especially as theyrelate to understanding the scientific issues affecting the as-sessment and management of ozone and particulate matter(PM) air pollutants. In my comments, I will provide a frame-work for air quality management, highlight some of the cur-rent data regarding the effects of ozone and PM on publichealth, and then present research needs and priorities, focus-ing on those associated with airborne particulate matter. Re-search is underway to address the highest priority researchneeds, the products of which include methods, models anddata that will improve and expand the science to be consid-ered in future reviews of the National Ambient Air QualityStandards (NAAQS), and will support standardsimplementation.* Dr. Vandenberg is currently National Research Program Director forparticulate matter and Assistant Director of the U.S. Environmental ProtectionAgency's National Health and Environmental Effects Research Laboratory,where he has primary responsibility for strategic planning and implementationof EPA's particulate matter research program. Prior to his current position, heserved as an environmental scientist for the Pollutant Assessment Branch ofEPA and for the Reproductive and Cancer Hazard Assessment Section of theCalifornia Department of Health Services. Dr. Vandenberg received his M.S.and Ph.D. in Biophysical Ecology from Duke University and he is currently anAdjunct Assistant Professor at the Nicholas School of the Environment. He is amember of the Society for Risk Analysis, the Air and Waste Management Asso-ciation, and the American Meteorological Society. His writings regarding airquality and health risk assessment have been extensively published. This man-uscript has been reviewed by the National Health and Environmental EffectsResearch Laboratory of the U.S. Environmental Protection Agency and hasbeen approved for publication. The views and opinions are those of the authorand do not reflect Agency positions or policy.154 PACE ENVIRONMENTAL LAW REVIEWThe framework for air quality management that is gen-erally used in the United States is shown in Figure 1. Asindicated, health and exposure research is used in establish-ing national air quality standards. Once standards are estab-lished, state and local agencies assess the condition of theenvironment, determine if an area is in attainment with thestandards, and develop State Implementation Plans (SIPs)that set a course for the states toward meeting the standards.Research supports implementation of the standards throughdevelopment of improved monitoring and modeling methodsand control technology development and evaluation. Thismorning, the standards setting process was described byother speakers in some detail. I would like to build on theearlier presentations and discuss the way the review of thescience not only supports standards review, but also benefitsresearch planning.Figure 1Framework for Air QualityManagementEffects/Exposure Goal: NAAQSResearchEnvironmental conditionsMonitoring/ModelingImplementation . /Research (atmos.science,mgmt)State Plans:Enforcement/ 4 Mobile, StationaryCompliance Source Controls, etc.The NAAQS review and revision process is diagramed inFigure 2. To begin the process, data published in peer re-viewed publications such as scientific journals are summa-[Vol. 162http://digitalcommons.pace.edu/pelr/vol16/iss1/51998] CLEAN AIR COLLOQUIUM 55rized in an air quality criteria document (CD).1 Dr. Thurstonmentioned that this document is the thickness of approxi-mately three Manhattan phone books. This document is re-viewed by the Clean Air Scientific Advisory Committee(CASAC), 2 a group of prominent independent scientists whoensure that the data is properly represented and interpreted.Relevant information is then evaluated by the regulatory pro-gram, which produces a Staff Paper and risk assessment thatinterprets and utilizes the information from the CD in thecontext of standard setting. Again, the CASAC reviews theStaff Paper to ensure appropriate data interpretation. TheStaff Paper serves as a link between the scientific criteriaand the regulatory decision making process. A proposedNAAQS decision is made by EPA Administrator, which goesthrough public hearings and a review and comment process.3With due consideration to the public comments, the Adminis-trator makes the final decisions on the standards.Figure 2NAAQS Review/Revision ProcessResearch on: Atnios. _-_R-_wa~ EPA Air EPA StaffProcesses, Air Qusl., _0jPeerei wed d Quality Paper (SP)Exposure, Heath and Published Studies Critea and RiskWelfare Effects Dornt Assessment$(ACD) (RA)// iResearch Research Needs R bPlanning& -r dentification rI theCoordination & Prioritizationubc I-, . . .- - -Final PublicDecisions on Hearings and Decisions onStan Coenent on StnadProposalsCASAC = Clean Air Scientific Advisory Committee1. See U.S. Envtl. Protection Agency, Air Quality Criteria Document forOzone and Related Photochemical Oxidants, EPA/600/AP/93/004a-c (1996).2. See Clean Air Act § 108(a)(2), 42 U.S.C. § 7408(a)(2) (1994).3. See National Ambient Air Quality Standards for Particulate Matter, 40C.F.R. pt. 50 (1997).356 PACE ENVIRONMENTAL LAW REVIEWThe dashed lines show that not only is the process mov-ing toward standards setting, but also there is the simultane-ous identification of research needs, which are documented tosupport research planning and prioritization.Earlier today, someone suggested that EPA has morelawyers than scientists. I beg to differ. We have a large andvigorous scientific research program. In EPA's NationalHealth and Environmental Effects Research Laboratoryalone, we have fifty scientists working full time on particulatematter research. My laboratory is just one of the three EPAlaboratories engaged in PM research which, together, focuson the highest priorities and produce scientific results impor-tant to the review and standards implementation processes.So, what does the current data show? Dr. Thurston re-viewed the science underlying the proposed and final stan-dards for ozone and PM. Therefore, I will briefly discuss thescientific basis for these standards. In the case of ozone, thescientific basis for the standards includes the following:the extensive review of thousands of scientific studies,which identified more than one hundred and eighty keyhealth effects studies as a basis for the new (1997) NAAQS;these studies indicate that ozone levels below the pre-1997 NAAQS (i.e., 0.12 parts per million for one hour) cancause significant health effects in children and other sus-ceptible groups.The effects from ozone include:moderate (-15%) to large (>20%) decreases in lungfunction (resulting in, e.g., difficulty in breathing or short-ness of breath);respiratory symptoms such as those associated withchronic bronchitis (e.g., aggravated/prolonged coughingand chest pain);increased respiratory problems (e.g., aggravation ofasthma, susceptibility to respiratory infection) resulting inincreased hospital admissions and emergency room visits;repeated exposures could result in chronic inflamma-tion and structural changes in the lungs;growing evidence suggests an association with prema-ture death.[Vol. 164http://digitalcommons.pace.edu/pelr/vol16/iss1/5CLEAN AIR COLLOQUIUMBased on a review of the scientific data, the CASACunanimously recommended that EPA replace the one-hourstandard with an eight-hour standard to protect againstlonger exposures (six to eight hours) related to health effectsat lower concentrations under more typical exposureconditions.The bottom line is that scientific data are summarized,evaluated and reviewed by CASAC to ensure that the stan-dards have a scientific basis.I would like to share one point that has arisen from ourstudies. In EPA research facilities, we study volunteers ina clinical setting. Often they are healthy college students,though we also conduct studies with children and people whohave preexisting cardiopulmonary and other diseases. Whatwe have found is that among a seemingly 'normal' population,some individuals respond quite dramatically to relatively lowozone exposures, while others are not apparently affectedmuch, if at all, at relatively high exposure levels. To use anexample, there are perhaps sixty people in the audience to-day. Some of you, including individuals who are not asthmat-ics, are likely to respond to low ozone exposures; others wouldnot. We cannot, at this time, tell which of you will respond,but we have found that there is a broad distribution in re-sponse among the population. It is not clear to us why somepeople in the general population respond to ozone and othersdo not. The NAAQS are intended to protect more susceptiblesubpopulations. We have yet to develop a biomarker or otherindicator that tells us who are the responders, and who arenot. Finally, I would like to reinforce the point that responseswe are seeing are in people like you and me. These results donot represent an extrapolation from animal studies, thoughwe use animal studies to help elucidate mechanisms of cause-effect and to explore factors affecting susceptibility.I now will turn my comments to particulate matter.Again, there are many studies of the health effects of PM.For PM, the scientific basis for the standards includes thefollowing:1998]558 PACE ENVIRONMENTAL LAW REVIEWan extensive review of thousands of scientific studiesidentified more than eighty epidemiological studies as thebasis for the revised standards;more than sixty epidemiological studies found signifi-cant links between PM levels at or below the current stan-dards and premature death or serious illness;numerous studies indicate "fine" (i.e., PM2.5)4 and "coarse"(PM2.5.1o)5 fractions of PM10 behave in fundamentally differ-ent ways.The effects from PM exposures include:increased premature deaths, primarily in the elderlyand those with heart or lung disease;aggravation of respiratory and cardiovascular illnessleading to hospitalizations and emergency room visits inindividuals with heart or lung disease and in children;lung function decrements and symptomatic effectssuch as those associated with chronic bronchitis, particu-larly in children and asthmatics;increased work loss days and school absences;changes to lung structure and natural defensemechanisms.Based on review of the scientific data, during the 1997NAAQS review process nineteen of twenty-one CASAC panelmembers recommended revising the then-current PM10 stan-dards by adding standards for fine particles. CASAC unani-mously recommended retaining at least one or more PM 10standards.A great deal of PM-related research has been conducted,yet I would not be a scientist if I did not point out that therealso are uncertainties. We expect these uncertainties. I wasasked, last summer, "Aren't you disturbed by these uncer-tainties and the research that is available for particulatematter?" I responded that, as a scientist, I am accustomed touncertainties. It is what we expect. The evaluation of thoseuncertainties requires a judgment call. We look to CASAC to4. "Fine" particles are those which pass through a size selective inlet witha 50% cutoff at 2.5 um aerodynamic diameter.5. "Course" particles are those which pass through a size selective inletwith a 50% cutoff at 10 um aerodynamic diameter, less the PM 2.5 mass fraction.[Vol. 166http://digitalcommons.pace.edu/pelr/vol16/iss1/5CLEAN AIR COLLOQUIUMhelp ensure that the judgment regarding what the standardshould be is based on the best available science, but the judg-ment itself is made in the face of uncertainty.Given the 1997 NAAQS decisions,6 where do we go fromhere? At this time the scientific community is conductingmany studies to improve the scientific data for future stan-dards review and implementation. For the next PM reviewwe are on a time line in which we need to have studies com-pleted and accepted for publication in the peer reviewed liter-ature by early in the year 2000. Research, however, takestime. Typically, several years may elapse from the initiationof a study to the publication of results. To ensure that thehighest priority needs are targeted with resources, we need toemploy an extensive research planning process. Simply put,the research needs (represented by the dashed lines in Figure2) are evaluated to identify the most significant data gapsand priorities. The priorities are compared with the currentand planned inventory of research activities underway in thescientific community, at EPA and at other research organiza-tions. Workshops and extensive engagement of the scientificcommunity help to develop a consensus about what the cur-rent and future research directions and priorities should be.Based on this process, EPA and other organizations allocatetheir resources accordingly, and the scientific data generationand review process cycles again, as indicated in Figure 2.In consultation with the scientific community, EPA hasdeveloped the following list of some priority needs for particu-late matter to develop a better understanding of these impor-tant areas:elucidate causal biological mechanisms;identify factors affecting susceptibility;characterize key components producing toxicity;characterize effects of long-term exposure;develop exposure-dose-response relationships;6. See National Ambient Air Quality Standards for Particulate Matter, 40C.F.R. pt. 50 (1997).1998]760 PACE ENVIRONMENTAL LAW REVIEWunderstand exposure relationships (central monitorsversus actual human exposures);develop improved measurement methods;develop atmospheric chemistry and models;characterize emissions.This is both a short list, and a tall order. In recognizingthe importance of improving and expanding the evidenceavailable for the next round of the PM criteria document de-velopment and NAAQS review, President Clinton wrote:The EPA, in partnership with other Federal agencies, willdevelop a greatly expanded coordinated interagency PMresearch program. The program will contribute to ex-panding the science associated with particulate matterhealth effects, as well as developing improved monitoringmethods and cost-effective mitigation strategies. 7EPA has taken on this charge and is looking at both thepublic and private sectors to develop a research program toaddress the priority scientific questions. The point here isthat it is not just EPA that is performing research to addressthe priority research needs. At EPA we have a vigorous re-search program. We are extensively coordinating our re-search program with other agencies, including theDepartment of Health and Services, the Health Effects Insti-tute (which represents a public/private partnership focusedon health and exposure issues), the North American Re-search Strategy for Tropospheric Ozone (NARSTO, anotherpublic/private research partnership focused on atmosphericsciences issues) and others. This ensures that your tax dol-lars are spent in the most efficient and effective manner.To summarize, I believe the evidence available todayshows that ozone and particulate matter present in ambientair are associated with significant health effects. There areuncertainties in the science, and various scientists may offerdiffering interpretations of the available data and the signifi-7. Implementation Plan for Revised Air Quality Standards for Ozone andParticulate Matter attached to memorandum from President Clinton to CarolBrowner, EPA Administrator (July 16, 1997) (on file with speaker).[Vol. 168http://digitalcommons.pace.edu/pelr/vol16/iss1/5CLEAN AIR COLLOQUIUMcance of the uncertainties. Scientists generally accept thatuncertainties exist. These uncertainties present researchchallenges that we are trying to address. We are looking be-yond the public agencies, to partners in the private sector andpublic/private partnerships, to ensure the coordination of re-search and to ensure that the uncertainties are addressed ina timely fashion.In the future, I believe we will reap significant benefitsfrom the research and regulatory review process. As timepasses, I think that we will have new methods, models anddata needed to make ever more confident risk managementdecisions. In addition, I expect increasing recognition of thecombined influence of ozone, particulate matter, sulfur oxide,nitrogen oxide and hazardous air pollutants on health out-comes. In other words, I believe we will move, at least in theresearch context, toward studies of the real atmospheres towhich people are exposed. Since we are exposed to a mixtureof pollutants in our daily lives, we need to evaluate the poten-tial synergistic or antagonistic effects of pollutants in combi-nation on health. This, to me, is an important futuredirection for our research programs.199819

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