Office of Research and Development National Health and Environmental Effects Research Laboratory Public Health and Components of Particulate Matter: The Changing Assessment of Black Carbon Comments by: David Diaz-Sanchez Office of Research and Development Although this presentation has been reviewed and approved by the U.S. Environmental Protection Agency. The views expressed in this presentation do not necessarily represent the views or policies of the U.S. EPA

Office of Research and Development National Health and Environmental Effects Research Laboratory Strengths of the review Encompasses a large literature Provides historical background Covers multiple lines of research Epidemiology Clinical Toxicology Exposure Identifies different issues in Developing Countries Emphasizes that reduction in BC may have health benefits 2

Office of Research and Development National Health and Environmental Effects Research Laboratory What the review reinforces Research on health effects of BC continues to rapidly expand Strong evidence supporting that ambient BC exposure may be associated with adverse cardiovascular effects BC is associated with increases in hospital admissions and ED visits, as well as mortality Though not as strong, evidence is also accumulating for an association between BC and other health endpoints and mortality Studies suggest that mitigating black carbon may have benefits on public health 3

Office of Research and Development National Health and Environmental Effects Research Laboratory National Ambient Air Quality Standards (NAAQS) 4 Mandated under the Clean Air Act and Amendments Standards for 6 criteria air pollutants Requires review of science and standards every 5 years Integrated Science Assessments: comprehensive review of policy-relevant science related to air pollutant

Office of Research and Development National Health and Environmental Effects Research Laboratory 2009 PM Integrated Science Assessment 5 “many constituents of PM can be linked with differing health effects and the evidence is not yet sufficient to allow differentiation of those constituents or sources that are more closely related to specific health outcomes” In 2012, EPA concluded available information was too limited to support alternative indicators and retained mass-based PM 2.5 and PM 10 indicators in final rule (78 FR 3086)

Office of Research and Development National Health and Environmental Effects Research Laboratory Premature death related to BC exposure World Health Organization: Health Effects of Black Carbon, 2012 Meta-analysis of results from studies on hospital admissions, ED visits, and mortality Most individual studies in the meta-analysis found that effects were similar for black carbon particles and PM

Office of Research and Development National Health and Environmental Effects Research Laboratory Respiratory health effects of BC Studies measure: –Markers of airway inflammation –Lung function –Asthma incidence/exacerbation –Respiratory symptoms –Hospital admissions/ED visits –Mortality 7 Adapted from

Office of Research and Development National Health and Environmental Effects Research Laboratory Respiratory health effects of BC 8 Bell et al. Am J Resp Crit Care Med, 179: , % Respiratory health effects of BC Hospital admissions/ED visits Bell et al. Am J Resp Crit Care Med, 179: , 2009 Hospital admissions/ED visits

Office of Research and Development National Health and Environmental Effects Research Laboratory The USC Children’s Health Study O3O3O3O3 PM 10 NO 2 Acid EC PM 2.5

Office of Research and Development National Health and Environmental Effects Research Laboratory Both local exposure to freeways and regional air pollution have detrimental, and independent, effects Distance to Freeway Regional PM 2.5 >1,500m<500m LowBest-80 ml High (e.g. L.A. air)-100 ml-180 ml Estimated deficits in 8-yr FEV1 growth, relative to living >1,500m from a freeway in the lowest PM 2.5 community (Gauderman et al, Lancet, 2007)

Office of Research and Development National Health and Environmental Effects Research Laboratory Reducing BC from Mobile Sources BC emissions from U.S. mobile diesel engines controlled via: Emissions standards for new engines, including requirements resulting in use of diesel particulate filters (DPFs) in conjunction with ultra low sulfur diesel fuel. Standards are for PM and are “technology forcing.” Reductions estimated from emissions models used in regulatory packages On road BC, OC, PM inventory from MOVES Nonroad BC inventory from PM for NONROAD model Locomotive, commercial marine, and aircraft emissions estimated separately from models Retrofit programs for in-use mobile diesel engines, such as EPA’s National Clean Diesel Campaign and the SmartWay Transport Partnership Program. 11

Office of Research and Development National Health and Environmental Effects Research Laboratory Projected Decline in BC Emissions from Mobile Sources 12 Total U.S. mobile source BC emissions are projected to decline by 86% by 2030 due to regulations already promulgated.

Office of Research and Development National Health and Environmental Effects Research Laboratory Role of wildfires and biomass burning 13 As diesels become more controlled, % of other sources of BC will grow Biomass burning BC dominated by prescribed and wild fires Biomass burning has significant BC emissions, but a lot more OC emissions

Office of Research and Development National Health and Environmental Effects Research Laboratory Rappold AG et al. Environ. Health Perspectives 2011 Percent change in cumulative RR by discharge diagnosis category for exposed and referent counties in NC during 3-day period of high exposure compared with the entire 6-week study period. Wildfire Regional Health Effects 2008 Pocosin Lakes National Wildlife Refuge Peat Fire

Office of Research and Development National Health and Environmental Effects Research Laboratory In October 2009, Congress requested that EPA conduct a In October 2009, Congress requested that EPA conduct a comprehensive study on black carbon to evaluate domestic and international sources, and climate/health impacts. EPA completed this report on March 30, Available online at: 15

Office of Research and Development National Health and Environmental Effects Research Laboratory BC contributes to the adverse impacts on human health, ecosystems, and visibility associated with PM 2.5 BC mitigation strategies, which lead to reductions in fine particles, can provide substantial public health and environmental benefits The most promising mitigation options for BC are consistent with current control opportunities 16

Office of Research and Development National Health and Environmental Effects Research Laboratory Thinking More Broadly Very large body of information on PM health risks compared to emerging BC literature BC is a marker for a multipollutant mixture While the evidence for associations between BC and health endpoints is accumulating quickly, it is still very difficult to disentangle the effects of individual components of the PM mixture from effects that are attributable to the mixture as a whole There is a need to expand on this work with a more comprehensive review –Consideration of role of other components & alternative interpretations –Respiratory endpoints –Inclusion of non-traffic studies –Impact of future trends 17