title: Effect of air pollution control on life expectancy in the United States: an analysis of 545 U.S. counties for the period from 2000 to 2007.
abstract: BACKGROUND
  In recent years (2000-2007), ambient levels of fine particulate matter (PM2.5) have continued to decline as a result of interventions, but the decline has been at a slower rate than previous years (1980-2000). Whether these more recent and slower declines of PM2.5 levels continue to improve life expectancy and whether they benefit all populations equally is unknown.
  
  
  METHODS
  We assembled a data set for 545 U.S. counties consisting of yearly county-specific average PM2.5, yearly county-specific life expectancy, and several potentially confounding variables measuring socioeconomic status, smoking prevalence, and demographic characteristics for the years 2000 and 2007. We used regression models to estimate the association between reductions in PM2.5 and changes in life expectancy for the period from 2000 to 2007.
  
  
  RESULTS
  A decrease of 10 μg/m in the concentration of PM2.5 was associated with an increase in mean life expectancy of 0.35 years (SD = 0.16 years, P = 0.033). This association was stronger in more urban and densely populated counties.
  
  
  CONCLUSIONS
  Reductions in PM2.5 were associated with improvements in life expectancy for the period from 2000 to 2007. Air pollution control in the last decade has continued to have a positive impact on public health.
authors.affiliation: From the Department of Biostatistics, Harvard School of Public Health, Boston, MA 02115, USA.
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Correia
authors.forename: C Arden
authors.initials: CA
authors.lastname: Pope
authors.forename: Douglas W
authors.initials: DW
authors.lastname: Dockery
authors.forename: Yun
authors.initials: Y
authors.lastname: Wang
authors.forename: Majid
authors.initials: M
authors.lastname: Ezzati
authors.forename: Francesca
authors.initials: F
authors.lastname: Dominici
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000393:Air Pollutants / Q000032:analysis / Q000633:toxicity*; D000397:Air Pollution / Q000009:adverse effects / Q000032:analysis / Q000517:prevention & control* / Q000706:statistics & numerical data; D003430:Cross-Sectional Studies; D004781:Environmental Exposure / Q000009:adverse effects / Q000032:analysis / Q000517:prevention & control*; D004784:Environmental Monitoring; D005260:Female; D006801:Humans; D008017:Life Expectancy / Q000639:trends*; D016014:Linear Models; D008297:Male; D052638:Particulate Matter / Q000032:analysis / Q000633:toxicity*; D014481:United States; D014504:Urban Health
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter