Environmental Health: A Global Access Science Source
Volume 18, Issue 1, 2019

Low concentrations of fine particle air pollution and mortality in the Canadian Community Health Survey cohort (Article) (Open Access)

Christidis T.* , Erickson A.C. , Pappin A.J. , Crouse D.L. , Pinault L.L. , Weichenthal S.A. , Brook J.R. , Van Donkelaar A. , Hystad P. , Martin R.V. , Tjepkema M. , Burnett R.T. , Brauer M.
  • a Health Analysis Division, Statistics Canada, 100 Tunney's Pasture Driveway, Ottawa, ON K1A 0T6, Canada
  • b School of Population and Public Health, University of British Columbia, 2206 East Mall, Vancouver, BC V6T 1Z3, Canada
  • c Health Analysis Division, Statistics Canada, 100 Tunney's Pasture Driveway, Ottawa, ON K1A 0T6, Canada, Safe Environments Directorate, Health Canada, 269 Laurier Avenue West, Ottawa, ON K1A 0K9, Canada
  • d Department of Sociology, University of New Brunswick, PO Box 4400, Fredericton, NB E3B 5A3, Canada
  • e Health Analysis Division, Statistics Canada, 100 Tunney's Pasture Driveway, Ottawa, ON K1A 0T6, Canada
  • f Department of Epidemiology, Biostatistics and Occupational Health, McGill University, 1110 Pine Ave West, Montreal, QC H3A 1A3, Canada, Air Health Science Division, Health Canada, 269 Laurier Avenue West, Ottawa, ON K1A 0K0, Canada
  • g Dalla Lana School of Public Health, University of Toronto, 155 College Street, Toronto, ON M5T 1P8, Canada, Department of Chemical Engineering and Applied Chemistry, University of Toronto, 223 College St., Toronto, ON M5T 1R4, Canada
  • h Department of Physics and Atmospheric Science, Dalhousie University PO Box 15000, 6310 Coburg Road, Halifax, NS B3H 4R2, Canada, Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO 63130, United States
  • i College of Public Health and Human Sciences, Oregon State University, 2520 SW Campus Way, Corvallis, OR 97331, United States
  • j Department of Physics and Atmospheric Science, Dalhousie University PO Box 15000, 6310 Coburg Road, Halifax, NS B3H 4R2, Canada, Harvard-Smithsonian Center for Astrophysics, 60 Garden St, Cambridge, MA 02138, United States, Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO 63130, United States
  • k Health Analysis Division, Statistics Canada, 100 Tunney's Pasture Driveway, Ottawa, ON K1A 0T6, Canada
  • l Population Studies Division, Health Canada, 50 Columbine Driveway, Ottawa, ON K1A 0K9, Canada
  • m School of Population and Public Health, University of British Columbia, 2206 East Mall, Vancouver, BC V6T 1Z3, Canada

Abstract

Background: Approximately 2.9 million deaths are attributed to ambient fine particle air pollution around the world each year (PM2.5). In general, cohort studies of mortality and outdoor PM2.5 concentrations have limited information on individuals exposed to low levels of PM2.5 as well as covariates such as smoking behaviours, alcohol consumption, and diet which may confound relationships with mortality. This study provides an updated and extended analysis of the Canadian Community Health Survey-Mortality cohort: a population-based cohort with detailed PM2.5 exposure data and information on a number of important individual-level behavioural risk factors. We also used this rich dataset to provide insight into the shape of the concentration-response curve for mortality at low levels of PM2.5. Methods: Respondents to the Canadian Community Health Survey from 2000 to 2012 were linked by postal code history from 1981 to 2016 to high resolution PM2.5 exposure estimates, and mortality incidence to 2016. Cox proportional hazard models were used to estimate the relationship between non-accidental mortality and ambient PM2.5 concentrations (measured as a three-year average with a one-year lag) adjusted for socio-economic, behavioural, and time-varying contextual covariates. Results: In total, 50,700 deaths from non-accidental causes occurred in the cohort over the follow-up period. Annual average ambient PM2.5 concentrations were low (i.e. 5.9 μg/m3, s.d. 2.0) and each 10 μg/m3 increase in exposure was associated with an increase in non-accidental mortality (HR = 1.11; 95% CI 1.04-1.18). Adjustment for behavioural covariates did not materially change this relationship. We estimated a supra-linear concentration-response curve extending to concentrations below 2 μg/m3 using a shape constrained health impact function. Mortality risks associated with exposure to PM2.5 were increased for males, those under age 65, and non-immigrants. Hazard ratios for PM2.5 and mortality were attenuated when gaseous pollutants were included in models. Conclusions: Outdoor PM2.5 concentrations were associated with non-accidental mortality and adjusting for individual-level behavioural covariates did not materially change this relationship. The concentration-response curve was supra-linear with increased mortality risks extending to low outdoor PM2.5 concentrations. © 2019 The Author(s).

Author Keywords

Fine particulate matter Air pollution Fine particle air pollution PM2.5 Cohort study Mortality Canada

Index Keywords

alcohol consumption concentration response follow up human controlled study pollution exposure health impact air pollution smoking male Canada risk factor particulate matter concentration (composition) Incidence Article pollutant major clinical study adult cohort analysis atmospheric pollution mortality public health health survey
Link
https://www.scopus.com/inward/record.uri?eid=2-s2.0-85073121760&doi=10.1186%2fs12940-019-0518-y&partnerID=40&md5=194242236296f9589e1d3e00015bf9d1
DOI: 10.1186/s12940-019-0518-y
ISSN: 1476069X
Original Language: English