title: Temperature, ozone, and mortality in urban and non-urban counties in the northeastern United States.
abstract: BACKGROUND
  Most health effects studies of ozone and temperature have been performed in urban areas, due to the available monitoring data. We used observed and interpolated data to examine temperature, ozone, and mortality in 91 urban and non-urban counties.
  
  
  METHODS
  Ozone measurements were extracted from the Environmental Protection Agency's Air Quality System. Meteorological data were supplied by the National Center for Atmospheric Research. Observed data were spatially interpolated to county centroids. Daily internal-cause mortality counts were obtained from the National Center for Health Statistics (1988-1999). A two-stage Bayesian hierarchical model was used to estimate each county's increase in mortality risk from temperature and ozone. We examined county-level associations according to population density and compared urban (≥1,000 persons/mile(2)) to non-urban (<1,000 persons/mile(2)) counties. Finally, we examined county-level characteristics that could explain variation in associations by county.
  
  
  RESULTS
  A 10 ppb increase in ozone was associated with a 0.45% increase in mortality (95% PI: 0.08, 0.83) in urban counties, while this same increase in ozone was associated with a 0.73% increase (95% PI: 0.19, 1.26) in non-urban counties. An increase in temperature from 70°F to 90°F (21.2°C 32.2°C) was associated with a 8.88% increase in mortality (95% PI: 7.38, 10.41) in urban counties and a 8.08% increase (95% PI: 6.16, 10.05) in non-urban counties. County characteristics, such as population density, percentage of families living in poverty, and percentage of elderly residents, partially explained the variation in county-level associations.
  
  
  CONCLUSIONS
  While most prior studies of ozone and temperature have been performed in urban areas, the impacts in non-urban areas are significant, and, for ozone, potentially greater. The health risks of increasing temperature and air pollution brought on by climate change are not limited to urban areas.
authors.affiliation: Department of Environmental and Occupational Health, School of Public Health, Rutgers, The State University of New Jersey, Piscataway, NJ, USA. jaime.madrigano@rutgers.edu.
authors.forename: Jaime
authors.initials: J
authors.lastname: Madrigano
authors.affiliation: Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, USA.
authors.forename: Darby
authors.initials: D
authors.lastname: Jack
authors.affiliation: Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, USA.
authors.forename: G Brooke
authors.initials: GB
authors.lastname: Anderson
authors.affiliation: School of Forestry and Environmental Studies, Yale University, New Haven, CT, USA.
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Bell
authors.affiliation: Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, USA.
authors.forename: Patrick L
authors.initials: PL
authors.lastname: Kinney
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000009:adverse effects*; D001499:Bayes Theorem; D057231:Climate Change / Q000706:statistics & numerical data; D004781:Environmental Exposure / Q000009:adverse effects*; D004784:Environmental Monitoring / Q000706:statistics & numerical data*; D006801:Humans; D008875:Middle Aged; D009511:New England; D010126:Ozone / Q000032:analysis*; D012140:Respiratory Tract Diseases / Q000401:mortality*; D018570:Risk Assessment; D012424:Rural Population / Q000706:statistics & numerical data; D012621:Seasons; D013696:Temperature; D014505:Urban Population / Q000706:statistics & numerical data
chemical_list: D000393:Air Pollutants; D010126:Ozone