Do socioeconomic characteristics modify the short term association between air pollution and mortality? Evidence from a zonal time series in Hamilton, Canada.
To assess the short term association between air pollution and mortality in different zones of an industrial city. An intra-urban study design is used to test the hypothesis that socioeconomic characteristics modify the acute health effects of ambient air pollution exposure.
The City of Hamilton, Canada, was divided into five zones based on proximity to fixed site air pollution monitors. Within each zone, daily counts of non-trauma mortality and air pollution estimates were combined. Generalised linear models (GLMs) were used to test mortality associations with sulphur dioxide (SO(2)) and with particulate air pollution measured by the coefficient of haze (CoH).
Increased mortality was associated with air pollution exposure in a citywide model and in intra-urban zones with lower socioeconomic characteristics. Low educational attainment and high manufacturing employment in the zones significantly and positively modified the acute mortality effects of air pollution exposure.
Three possible explanations are proposed for the observed effect modification by education and manufacturing: (1) those in manufacturing receive higher workplace exposures that combine with ambient exposures to produce larger health effects; (2) persons with lower education are less mobile and experience less exposure measurement error, which reduces bias toward the null; or (3) manufacturing and education proxy for many social variables representing material deprivation, and poor material conditions increase susceptibility to health risks from air pollution.
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Cites: Epidemiology. 1999 Nov;10(6):661-210535775
Cites: Environ Health Perspect. 2000 Feb;108(2):109-1710656850
Cites: Environ Health Perspect. 1999 Aug;107(8):637-4110417361
Cites: Environ Health Perspect. 2000 Feb;108(2):125-3310656852
Cites: J Epidemiol Community Health. 2000 Jan;54(1):73-410692968
Cites: J Air Waste Manag Assoc. 2000 Jul;50(7):1081-9410939202
Cites: J Epidemiol Community Health. 2000 Oct;54(10):750-510990478
Cites: J Air Waste Manag Assoc. 2000 Aug;50(8):1287-9811002592
Cites: J Air Waste Manag Assoc. 2000 Aug;50(8):1501-1311002610
Cites: Environ Health Perspect. 2000 Dec;108(12):A544-511133408
Cites: J Expo Anal Environ Epidemiol. 2000 Nov-Dec;10(6 Pt 1):533-4311140437
Cites: Environ Res. 2001 May;86(1):12-2511386737
Cites: Environ Res. 2001 May;86(1):26-3611386738
Cites: J Expo Anal Environ Epidemiol. 2001 Jul-Aug;11(4):286-9411571608
Cites: J Am Stat Assoc. 1978;73(363):463-7212262745
Cites: J Air Waste Manag Assoc. 2002 Apr;52(4):470-8412002192
Cites: Am J Epidemiol. 2002 Aug 1;156(3):193-20312142253
Cites: JAMA. 2002 Aug 21;288(7):830; author reply 83012186593
Cites: J Expo Anal Environ Epidemiol. 2002 Nov;12(6):427-3212415491