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Goods Movement Conference: Public Health Implications for the Mid-Atlantic Region University of Pennsylvania Houston Hall – Bodek Lounge Philadelphia, Pennsylvania Friday, September 23, 2011 . Diesel Pollution Cancer and Other Health Risks. Kevin M. Stewart Director of Environmental Health
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Goods Movement Conference: Public Health Implications for the Mid-Atlantic RegionUniversity of PennsylvaniaHouston Hall – Bodek LoungePhiladelphia, PennsylvaniaFriday, September 23, 2011
Diesel Pollution Cancer and Other Health Risks Kevin M. Stewart Director of Environmental Health American Lung Association of the Mid-Atlantic
Outline Diesel Exhaust Composition Diesel Health Effects Overview Diesel Emissions as a Carcinogen Some Factors Associated with Goods Movement Influencing Health Outcomes Conclusion
Composition of Diesel Exhaust • Complex mixture of thousands of chemicals • Gases and fine particles • Over forty air contaminants recognized as toxins, carcinogens, reproductive and developmental hazards, endocrine disruptors
Composition of Diesel Exhaust • Gas phase Oxygen Carbon dioxide Nitrogen Carbon monoxide Water vapor Nitrogen Oxides (especially NO) Sulfur Compounds (especially Sulfur Oxides) Volatile Organic Compounds Low MW Hydrocarbons …
Composition of Diesel Exhaust • Gas phase components of toxicological significance Aldehydes (formaldehyde, acetaldehyde, acrolein) Benzene 1,3-butadiene nitrosamines polycyclic aromatic hydrocarbons (PAHs) nitro-PAHs
Composition of Diesel Exhaust • Particulate phase • Mostly elemental carbon (soot) • About 20% to 40% adsorbed organic compounds • Also sulfate, nitrate, metals, other trace elements • The most toxicologically relevant adsorbed compounds (less than 1% of PM by mass): - PAHs - Nitro-PAHs - Oxidized PAH derivatives • 92% of mass is in particles smaller than 1 micron
Diesel Exhaust Particles Elemental Carbon (EC) Unburned Fuel PAHs ... Dr. John Froines, Director, UCLA Southern California Particulate Center and Supersite Health Effects Institute, 1995
PM2.5 (2.5 mm) PM10 (10 mm) How small are these particles? Hair cross section (50-100 mm) PM0.1 (0.1 mm) Human Hair (50-100 mm diameter)
Where they go • Nose and Throat Remove Particles > 10mm • Trachea and Upper Bronchi remove Particles < 10mm and > 2.5 mm • Particles < 2.5 mm and >0.1 mm are deposited in Bronchioles and Alveoli • Ultrafine particles (<0.1 mm) reach all areas of lung and to some degree diffuse into body tissues
Substances in Diesel Exhaust Listed by the California Air Resources Board as Toxic Air Contaminants acetaldehyde cobalt compounds nickel acrolein cresol isomers 4-nitrobiphenyl aniline cyanide compounds phenol antimony compounds dibutylphthalate phosphorus arsenic dioxins and dibenzofurans POM, including PAHs benzene ethyl benzene and their derivatives beryllium compounds formaldehyde propionaldehyde biphenyl hexane selenium compounds bis[2-ethylhexyl]phthalate lead (inorganic) styrene 1,3-butadiene manganese compounds toluene cadmium mercury compounds xylene isomers, mixtures chlorine methanol o-xylenes chlorobenzene methyl ethyl ketone m-xylenes chromium compounds naphthalene p-xylenes
Diesel Exhaust is a “Quadruple Whammy” for Public Health • Carcinogens • Toxins • Fine Particulate Matter • Nitrogen Oxides
Whammies 1 and 2 • Carcinogens • Lung • Bladder • Toxins • Nervous • Endocrine • Reproductive • Immune • Developmental • Liver • Kidney
Whammy 3 • Fine Particulate Matter • Premature death from respiratory and cardiovascular causes, as well as stroke • Increased hospitalization and emergency visits for heart attacks, strokes, and acute respiratory illnesses • Exacerbation of asthma • Increased frequency, severity, and duration of episodes/attacks • Increased symptom days and absenteeism • Increased emergency visits and hospitalizations
Whammy 4 • Nitrogen Oxides • Ozone precursor … • Premature death • Increased asthma attacks/episodes • Increased need for medical treatment, emergency visit, and hospitalization for persons with chronic lung disease • Increased susceptibility to respiratory infections • Decrease in lung function growth
Estimated Cancers from Diesel Particulate State and Territorial Air Pollution Program Administrators and Association of Local Air Pollution Control Officials (STAPPA/ALAPCO, now NACAA) Cancer Risk from Diesel Particulate: National and Metropolitan Area Estimates for the United States, March 15, 2000.
Estimated Cancers from Diesel Particulate ENTIRE UNITED STATES 125,110 20 Largest Metropolitan Areas Metropolitan Area Cancers Los Angeles 16,250 New York 10,360 Chicago 4,535 Washington/Baltimore 3,750 San Francisco 3,510 Philadelphia 3,085 Boston 2,900 Detroit 2,810 Dallas/Fort Worth 2,470 - continued...
Estimated Cancers fromDiesel Particulate 20 Largest Metropolitan Areas - continued Metropolitan Area Cancers Houston 2,270 Atlanta 1,930 Miami/Fort Lauderdale 1,880 Seattle 1,765 Phoenix 1,510 Cleveland 1,500 Minneapolis 1,460 San Diego 1,430 St. Louis 1,320 Denver 1,220 Pittsburgh 1,210
Cancer Risk Assessments of Diesel Exhaust ORGANIZATION YEAR CONCLUSION National Institute for Occupational Safety and Health 1988 potential occupational carcinogen International Agency for Research on Cancer (WHO) 1989 probable human carcinogen State of California 1990 known to cause cancer Health Effects Institute 1995 & World Health Organization 1996 consistency in showing weak association between exposure to diesel exhaust and lung cancer
Cancer Risk Assessments of Diesel Exhaust ORGANIZATION YEAR CONCLUSION California EPA (Staff Recommendation) 1998 “may cause an increase in the likelihood of cancer” California Air Resources Board 1998 diesel particulate emissions are a toxic air contaminant National Toxicology Program 1998 “diesel exhaust particulate is reasonably anticipated to be a human carcinogen” U.S. Environmental Protection Agency 2002 likely to be carcinogenic to humans by inhalation at environmental levels of exposure
Cancer Risk Assessments of Diesel Exhaust • In a presentation to the Mid-Atlantic Clean Diesel Collaborative in 2010, EPA’s Rich Cook noted: • Strong desire among many stakeholders to develop a cancer Unit Risk Estimate for diesel exhaust. • Most recent request from National Environmental Justice Advisory Committee (NEJAC) • EPA Response: Data still inadequate to develop unit risk estimate. • Issue is [wide variation in] dose response relationships in epidemiology studies • However, EPA will continue to control emissions to the maximum extent possible.
Cancer Risk Assessments of Diesel Exhaust • California Office of Environmental Health Hazard Assessment has made estimates of risk: • Estimated range of lung cancer risk (upper 95% confidence interval) based on human epidemiological data is 1.3 x 10-4 to 2.4 x 10-3 per µg/m3. • Overall, after considering the results of the meta-analysis of human studies, as well as the detailed analysis of railroad workers, the Scientific Review Panel concluded that 3 x 10-4 per µg/m3 is a reasonable estimate of unit risk expressed in terms of diesel particulate.
Carcinogenic Potentialof Diesel Emissions • Carcinogens in vapor phase • Benzene • Formaldehyde • 1,3-butadiene • Ethylene dibromide • Adsorbed onto particles • 3 PAHs (including BAP) classified as probably carcinogenic to humans • At least 16 hydrocarbons classified as possibly carcinogenic to humans • These do not account for all of the cancer risk associated with diesel exhaust.
Carcinogenic Potential of Diesel Emissions • Meta-analysis by California Office of Environmental Health Hazard Assessment on diesel exhaust and lung cancer: • Clear positive relationship between occupational diesel exhaust and lung cancer • Cigarette smoking removed as confounder • Consistent with causal relationship • Association with 40% increase in relative risk
Carcinogenic Potential of Diesel Emissions • Over thirty studies have investigated the exposure of bus and truck drivers, railroad and shipyard workers to diesel exhaust. • A meta-analysis on diesel exhaust and bladder cancer (January, 2001 by Boffetta and Silverman in Epidemiology): • Found an increased risk of between 18% and 76% among occupationally exposed individuals.
Carcinogenic Potential of Diesel Emissions • People are exposed to hundreds of times the amount of carcinogens the Environmental Protection Agency recognizes as reasonably allowable (levels yielding a one-in-a-million risk): • In 1996 the national average lifetime cancer risk from breathing outdoor hazardous pollutants was 1 in 2,100. • Mobile sources: 93% of this risk • Diesel emissions: over 95% of the mobile sources’ contribution (89% of the total)
Carcinogenic Potential of Diesel Emissions • In 2005, Clean Air Task Force estimated: • Average lifetime nationwide cancer risk due to diesel exhaust is over 350 in a million. • Residents from more than two-thirds of all U.S. counties face a cancer risk from diesel exhaust greater than 100 deaths per million population. • People living in eleven urban counties face diesel cancer risks greater than 1,000 in a million. • The risk of lung cancer from diesel exhaust for people living in urban areas is three times that for those living in rural areas.
Some Factors Associated with Goods Movement Influencing Health Outcomes
Nature of Sources Big Old Dirty Inefficient
Nature of Fuels Finally, where highway diesel has needed to be at 15 ppm, other diesel fuel has been at 500 ppm sulfur. (Clean Diesel Fuel Alliance) Fuels used in shipping, where emissions have been virtually unregulated, run from 1 – 5 percent sulfur.
Proximity (Prof. Andrea Hricko, Keck Sch. of Med. USC, 2011)
Proximity (Mike Nazemi, SCAQMD, Presentation, Mira Loma, CA, 2002) “If we have diesel sources, the best thing we can do is to keep them 500 meters away from people.”
Proximity PM2.5 comparison Newark, NJ (NJEF and CWA, 2006)
Proximity PM0.1 particle count comparison Newark, NJ (NJEF and CWA, 2006)
Concentration of Population(Population Density for Counties July 1, 2009)
Proximity as a Consequence Behavioral factors influenced by that highly populous environment: “Findings in published, peer-reviewed health research estimate that, although we spend only about six percent of our day commuting to and from work, over half of our exposure to these particles may occur during that travel time.” - George D. Thurston, Sc.D., NYU Sch. of Med.
Environmental Justice Concerns Racial and Ethnic Disparities Socioeconomic Disparities (Poverty) Disparities in Access to & Quality of Medical Care
Concluding RemarksObservation PM2.5 levels in traffic, Austin, TX (CATF, 2007) Cars only (MOPAC) With trucks (I-35)
One Part of the Solution Retrofitting with diesel particulate filters (CATF, 2007) Before After
We will breathe easier when the air in everyAmerican community is clean and healthy. We will breathe easier when people are free from the addictivegrip of cigarettes and the debilitating effects of lung disease. We will breathe easier when the air in our public spaces andworkplaces is clear of secondhand smoke.We will breathe easier when children no longerbattle airborne poisons or fear an asthma attack. Until then, we are fighting for air.