title: Spatial associations between socioeconomic groups and NO2 air pollution exposure within three large Canadian cities.
abstract: Previous studies of environmental justice in Canadian cities have linked lower socioeconomic status to greater air pollution exposures at coarse geographic scales, (i.e., Census Tracts). However, studies that examine these associations at finer scales are less common, as are comparisons among cities. To assess differences in exposure to air pollution among socioeconomic groups, we assigned estimates of exposure to ambient nitrogen dioxide (NO2), a marker for traffic-related pollution, from city-wide land use regression models to respondents of the 2006 Canadian census long-form questionnaire in Toronto, Montreal, and Vancouver. Data were aggregated at a finer scale than in most previous studies (i.e., by Dissemination Area (DA), which includes approximately 400-700 persons). We developed simultaneous autoregressive (SAR) models, which account for spatial autocorrelation, to identify associations between NO2 exposure and indicators of social and material deprivation. In Canada's three largest cities, DAs with greater proportions of tenants and residents who do not speak either English or French were characterised by greater exposures to ambient NO2. We also observed positive associations between NO2 concentrations and indicators of social deprivation, including the proportion of persons living alone (in Toronto), and the proportion of persons who were unmarried/not in a common-law relationship (in Vancouver). Other common measures of deprivation (e.g., lone-parent families, unemployment) were not associated with NO2 exposures. DAs characterised by selected indicators of deprivation were associated with higher concentrations of ambient NO2 air pollution in the three largest cities in Canada.
authors.affiliation: Health Analysis Division, Statistics Canada, 100 Tunney's Pasture Way, Ottawa, ON, Canada K1A 0T6. Electronic address: Lauren.Pinault@canada.ca.
authors.forename: Lauren
authors.initials: L
authors.lastname: Pinault
authors.affiliation: Department of Sociology, University of New Brunswick, PO Box 440, Fredericton, NB, Canada E3B 5A3. Electronic address: Dan.Crouse@unb.ca.
authors.forename: Daniel
authors.initials: D
authors.lastname: Crouse
authors.affiliation: Fielding School of Public Health, University of California (Los Angeles), 650 Charles E. Young Drive S. Rm. 56-070 CHS, Mail Code: 177220, Los Angeles, CA 90095, United States. Electronic address: MJerrett@ucla.edu.
authors.forename: Michael
authors.initials: M
authors.lastname: Jerrett
authors.affiliation: School of Population and Public Health, University of British Columbia, 2206 East Mall, Vancouver, BC, Canada V6T 1Z3. Electronic address: Michael.Brauer@ubc.ca.
authors.forename: Michael
authors.initials: M
authors.lastname: Brauer
authors.affiliation: Health Analysis Division, Statistics Canada, 100 Tunney's Pasture Way, Ottawa, ON, Canada K1A 0T6. Electronic address: Michael.Tjepkema@canada.ca.
authors.forename: Michael
authors.initials: M
authors.lastname: Tjepkema
mesh_terms: D000328:Adult; D000397:Air Pollution / Q000706:statistics & numerical data*; D002170:Canada; D002947:Cities / Q000706:statistics & numerical data*; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide; D012959:Socioeconomic Factors; D001335:Vehicle Emissions
chemical_list: D001335:Vehicle Emissions; D009569:Nitric Oxide
keywords: Air pollution; Canada; NO(2); Nitrogen dioxide; Socioeconomic status; Traffic