A Cohort Study of Traffic-Related Air Pollution and Mortality in Toronto, Ontario, Canada

Abstract

BackgroundChronic exposure to traffic-related air pollution (TRAP) may contribute to premature mortality, but few studies to date have addressed this topic.ObjectivesIn this study we assessed the association between TRAP and mortality in Toronto, Ontario, Canada.MethodsWe collected nitrogen dioxide samples over two seasons using duplicate two-sided Ogawa passive diffusion samplers at 143 locations across Toronto. We calibrated land use regressions to predict NO2 exposure on a fine scale within Toronto. We used interpolations to predict levels of particulate matter with aerodynamic diameter ≤ 2.5 μm (PM2.5) and ozone levels. We assigned predicted pollution exposures to 2,360 subjects from a respiratory clinic, and abstracted health data on these subjects from medical billings, lung function tests, and diagnoses by pulmonologists. We tracked mortality between 1992 and 2002. We used standard and multilevel Cox proportional hazard models to test associations between air pollution and mortality.ResultsAfter controlling for age, sex, lung function, obesity, smoking, and neighborhood deprivation, we observed a 17% increase in all-cause mortality and a 40% increase in circulatory mortality from an exposure contrast across the interquartile range of 4 ppb NO2. We observed no significant associations with other pollutants.ConclusionsExposure to TRAP was significantly associated with increased all-cause and circulatory mortality in this cohort. A high prevalence of cardiopulmonary disease in the cohort probably limits inference of the findings to populations with a substantial proportion of susceptible individuals.

A rapid assessment of the impact of hazard reduction burning around Sydney, May 2016

“…The study compared mortality and pollution between populated regions and was not designed to investigate smaller scale variations in pollution (Krewski et al, 2009). By contrast, a cohort study in Toronto, using land use regression to predict NO 2 at the residential address and an interpolation method to predict PM 2.5 , did find a large effect on natural and cardiovascular mortality for NO 2 , but not for PM 2.5 (Jerrett et al, 2009b). Therefore, the authors modelled NO 2 together with traffic proximity (and not with PM 2.5 ), and the effects for NO 2 were slightly weakened, but still significant (from 1.40 (95% CI: 1.05-1.86) to 1.39 (95% CI: 1.05-1.85) per interquartile range of 7.6 µg NO 2 /m 3 ).…”

Long-path measurements of pollutants and micrometeorology over Highway 401 in Toronto

“…Laboratory studies have indicated that inhalation of fine particles and O 3 even for a short time causes acute conduit artery vasoconstriction (Brook, 2002). Studies in Toronto have shown that exposure to traffic-related air pollution is associated with respiratory conditions (Buckeridge et al, 2002), increased risk of circulatory mortality (Jerrett et al, 2009), cardiovascular mortality (Chen et al, 2013), ischemic heart disease (Beckerman et al, 2012), and childhood atopic asthma (Shankardass et al, 2015). Research results in other locations have also shown associated negative health effects, such as asthma (Lin et al, 2002;McConnell et al, 2006), cancer and leukemia (Pearson et al, 2000) in children, and development of obesity in children (Jerrett et al, 2014).…”

Cardiovascular diseases in the population of industrial towns and environmental factors

“…По результатам крупного популяционного исследова-ния, проведенного американскими исследователями, вы-явлено, что воздействие загрязнения воздуха существенно повышает смертность от нарушений кровообращения [11]. Z. Qian и соавт.…”