Research Health Benefits from Large-Scale Ozone Reduction in the United States Jesse D. Berman,1 Neal Fann,2 John W. Hollingsworth,3 Kent E. Pinkerton,3 William N. Rom,3 Anthony M. Szema,3 Patrick N. Breysse,1 Ronald H. White,4 and Frank C. Curriero1,5 1Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA; 2Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, USA; 3Environmental Health Policy Committee of the American Thoracic Society, Washington, DC, USA; 4RH White Consultants LLC, Silver Spring, Maryland, USA; 5Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA c onclusion k ey Background : Exposure to ozone has been associated with adverse health effects, including premature mortality and cardiopulmonary and respiratory morbidity. In 2008, the U.S. Environmental Protection Agency (EPA) lowered the primary (health-based) National Ambient Air Quality Standard (NAAQS) for ozone to 75 ppb, expressed as the fourth-highest daily maximum 8-hr average over a 24-hr period. Based on recent monitoring data, U.S. ozone levels still exceed this standard in numerous locations, resulting in avoidable adverse health consequences. o Bjectivs : We sought to quantify the potential human health benefits from achieving the cur- rent primary NAAQS standard of 75 ppb and two alternative standard levels, 70 and 60 ppb, which represent the range recommended by the U.S. EPA Clean Air Scientific Advisory Committee (CASAC). Methods : We applied health impact assessment methodology to estimate numbers of deaths and other adverse health outcomes that would have been avoided during 2005, 2006, and 2007 if the cur- rent (or lower) NAAQS ozone standards had been met. Estimated reductions in ozone concentrations were interpolated according to geographic area and year, and concentration–response functions were obtained or derived from the epidemiological literature. r sulte : We estimated that annual numbers of avoided ozone-related premature deaths would have ranged from 1,410 to 2,480 at 75 ppb to 2,450 to 4,130 at 70 ppb, and 5,210 to 7,990 at 60 ppb. Acute respiratory symptoms would have been reduced by 3 million cases and school-loss days by 1 million cases annually if the current 75-ppb standard had been attained. Substantially greater health benefits would have resulted if the CASAC-recommended range of standards (70–60 ppb) had been met. : Attaining a more stringent primary ozone standard would significantly reduce ozone-related premature mortality and morbidity. words : health benefits, health impact assessment, ozone, standards. Environ Health Perspect 120:1404–1410 (2012). http://dx.doi.org/10.1289/ehp.1104851 [Online 18 July 2012] review of scientific literature and provides advice to the U.S. EPA Administrator on the adequacy of the NAAQS. Based on its 2008 evidence review, the CASAC recommended adoption of a primary 8-hr average ozone standard in the 60- to 70-ppb range. A 2009 U.S. EPA research assessment reviewed ozone exposure and the respiratory-related mortal- ity evidence, including a pertinent long-term cohort study of 96 metropolitan statistical areas (MSAs) that estimated a 1.04 [95% con- fidence interval (CI): 1.01, 1.07] relative risk in cardiovascular mortality for each 10-ppb increase in ozone (Jerrett et al. 2009). In 2009, the U.S. EPA initiated a reconsideration of the 2008 ozone NAAQS and in 2010 proposed a revised standard in the range from 60 to 70 ppb for an 8-hr daily maximum (U.S. EPA 2010b). However, on 2 September 2011 the President of the United States requested the U.S. EPA Administrator defer review of the ozone NAAQS to 2013, citing concerns about regulatory uncertainty (Office of the Press Secretary 2011). Recent HIAs have estimated the expected human health benefits of attaining a more stringent ozone NAAQS in the future (Fann et al. 2011; U.S. EPA 2008b). The goal of the present analysis was to evaluate immediate health benefits that would result at nation- wide and regional levels from meeting the Address correspondence to F.C. Curriero, Depart- ment of Environmental Health Sciences, Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe St., Baltimore, MD 21205 USA. Telephone: (410) 614-5817. Fax: (410) 955-9334. Email: fcurrier@jhsph.edu Supplemental Material is available online (http:// dx.doi.org/10.1289/ehp.1104851). We thank G. Ewart for continued support. J.D.B. was supported by a training grant from the National Institute for Occupational Safety and Health Education and Research Center for Occupational Safety and Health and in part by U.S. Environmental Protection Agency (EPA) grant RD83241701. The American Thoracic Society provided some research guidance and financial support for J.D.B. Salary sup- port for F.C.C. and P.N.B. was provided in part by National Institute of Environmental Health Sciences grant ES03819 and for J.W.H. in part by National Institutes of Health grant ES016126. Contents of this article are solely the responsibility of the grantee and do not necessarily represent the views of the U.S. EPA. R.H.W. is employed by RH White Consultants LLC. The authors declare they have no actual or poten- tial competing financial interests. Received 13 December 2011; accepted 29 June. 2012. ovlume 120 | number 10 | October 2012 • Environmental Health Perspectives Tropospheric ozone is a secondary air pollutant that has been recognized as a serious public health risk [U.S. Environmental Protection Agency (EPA) 2008c]. Tropospheric ozone has been associated with adverse health effects, including decreased pulmonary func- tion, asthma exacerbations, increased hospi- tal and emergency department (ED) visits, and increased mortality (Choi et al. 2011; Dockery and Pope 1994; Levy et al. 2001; Mudway and Kelly 2000). Evidence of nega- tive health effects has been demonstrated by toxicological studies (Larsen et al. 2010), clini- cal trials (Gong et al. 1986), longitudinal epi- demiological studies (Bell et al. 2004; Gryparis et al. 2004; Huang et al. 2005; Ito et al. 2005; Levy et al. 2005; Schwartz 2005), and cohort epidemiological studies (Jerrett et al. 2009). Adolescents and individuals with existing chronic lung and cardiovascular disease have increased susceptibility to the adverse health effects of ozone (Burnett et al. 2001). The Clean Air Act (CAA 1970) mandated health-based national ambient air quality standards (NAAQS) set at a level “requisite to protect public health with an adequate margin of safety.” Health impact assess- ments (HIAs) are used to make informed and 1404 systematic decisions about regulatory policy based on estimates of positive and negative health impacts from proposed air pollution standards (Briggs et al. 2009). To systemize health impact estimations associated with air pollution, the U.S. EPA Office of Air Quality Planning and Standards uses the software tool Environmental Benefits Mapping and Analysis Program (BenMAP; Abt Associates Inc., Bethesda, MD) (U.S. EPA 2010a). The BenMAP interface can be used to predict changes in air pollution, quantify exposed populations, and estimate changes in health outcomes according to geographic location within the United States. BenMAP (U.S. EPA 2010a) has been applied to inform local and federal regulatory policies concern- ing exposure to ozone (Hubbell et al. 2005; U.S. EPA 2008b), PM2.5 (Davidson et al. 2007; Fann et al. 2011), and diesel exhaust (Connecticut Department of Environmental Protection 2009), to simulate climate change scenarios (Tagaris et al. 2010; Voorhees et al. 2011), and to conduct international assess- ments (Boldo et al. 2011). As required under the CAA (1970), the U.S. EPA Clean Air Scientific Advisory Committee (CASAC) performs a formal