title: Long-Term Ozone Exposure and Mortality in a Large Prospective Study.
abstract: BACKGROUND
  Tropospheric ozone (O3) is potentially associated with cardiovascular disease risk and premature death. Results from long-term epidemiological studies on O3 are scarce and inconclusive.
  
  
  OBJECTIVE
  In this study, we examined associations between chronic ambient O3 exposure and all-cause and cause-specific mortality in a large cohort of U.S. adults.
  
  
  METHODS
  Cancer Prevention Study II participants were enrolled in 1982. A total of 669,046 participants were analyzed, among whom 237,201 deaths occurred through 2004. We obtained estimates of O3 concentrations at the participant's residence from a hierarchical Bayesian space-time model. Estimates of fine particulate matter (particulate matter with an aerodynamic diameter of up to 2.5 μm [PM2.5]) and NO2 concentrations were obtained from land use regression. Cox proportional hazards regression models were used to examine mortality associations adjusted for individual- and ecological-level covariates.
  
  
  RESULTS
  In single-pollutant models, we observed significant positive associations between O3, PM2.5, and NO2 concentrations and all-cause and cause-specific mortality. In two-pollutant models adjusted for PM2.5, significant positive associations remained between O3 and all-cause (hazard ratio [HR] per 10 ppb, 1.02; 95% confidence interval [CI], 1.01-1.04), circulatory (HR, 1.03; 95% CI, 1.01-1.05), and respiratory mortality (HR, 1.12; 95% CI, 1.08-1.16) that were unchanged with further adjustment for NO2. We also observed positive mortality associations with both PM2.5 (both near source and regional) and NO2 in multipollutant models.
  
  
  CONCLUSIONS
  Findings derived from this large-scale prospective study suggest that long-term ambient O3 contributes to risk of respiratory and circulatory mortality. Substantial health and environmental benefits may be achieved by implementing further measures aimed at controlling O3 concentrations.
authors.affiliation: 1 McLaughlin Centre for Population Health Risk Assessment and.|2 Centre for Research in Environmental Epidemiology, Barcelona, Spain.|3 Universitat Pompeu Fabra, Barcelona, Spain.|4 CIBER Epidemiología y Salud Pública, Madrid, Spain.
authors.forename: Michelle C
authors.initials: MC
authors.lastname: Turner
authors.affiliation: 5 Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, Berkeley, California.
authors.forename: Michael
authors.initials: M
authors.lastname: Jerrett
authors.affiliation: 6 Department of Economics, Brigham Young University, Provo, Utah.
authors.forename: C Arden
authors.initials: CA
authors.lastname: Pope
authors.affiliation: 1 McLaughlin Centre for Population Health Risk Assessment and.|7 School of Epidemiology, Public Health and Disease Prevention, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada.
authors.forename: Daniel
authors.initials: D
authors.lastname: Krewski
authors.affiliation: 8 Epidemiology Research Program, American Cancer Society, Atlanta, Georgia.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Gapstur
authors.affiliation: 8 Epidemiology Research Program, American Cancer Society, Atlanta, Georgia.
authors.forename: W Ryan
authors.initials: WR
authors.lastname: Diver
authors.affiliation: 5 Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, Berkeley, California.
authors.forename: Bernardo S
authors.initials: BS
authors.lastname: Beckerman
authors.affiliation: 9 Department of Civil and Environmental Engineering, University of Washington, Seattle, Washington.
authors.forename: Julian D
authors.initials: JD
authors.lastname: Marshall
authors.affiliation: 5 Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, Berkeley, California.
authors.forename: Jason
authors.initials: J
authors.lastname: Su
authors.affiliation: 10 Department of Sociology, University of New Brunswick, Fredericton, New Brunswick, Canada; and.
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Crouse
authors.affiliation: 11 Population Studies Division, Health Canada, Ottawa, Ontario, Canada.
authors.forename: Richard T
authors.initials: RT
authors.lastname: Burnett
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000032:analysis / Q000706:statistics & numerical data*; D003643:Death; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010126:Ozone / Q000032:analysis*; D016016:Proportional Hazards Models; D011446:Prospective Studies; D011647:Puerto Rico / Q000453:epidemiology; D012306:Risk; D012307:Risk Factors; D013995:Time; D014481:United States / Q000453:epidemiology
chemical_list: D000393:Air Pollutants; D010126:Ozone
keywords: air pollution; mortality; ozone; prospective study