A New Method to Jointly Estimate the Mortality Risk of Long-Term Exposure to Fine Particulate Matter and its Components

Abstract

Most studies on the association between exposure to fine particulate matter (PM2.5) and mortality have considered only total concentration of PM2.5 or individual components of PM2.5, and not the combined effects of concentration and particulate composition. We sought to develop a method to estimate the risk of death from long-term exposure to PM2.5 and the distribution of its components, namely: sulphate, nitrate, ammonium, organic mass, black carbon, and mineral dust. We decomposed PM2.5 exposure into the sum of total concentration and the proportion of each component. We estimated the risk of death due to exposure using a cohort of ~2.4 million Canadians who were followed for vital status over 16 years. Modelling the concentration of PM2.5 with the distribution of the proportions of components together was a superior predictor for mortality than either total PM2.5 concentration alone, or all component concentrations modelled together. Our new approach has the advantage of characterizing the toxicity of the atmosphere in its entirety. This is required to fully understand the health benefits associated with strategies to improve air quality that may result in complex changes not only in PM2.5 concentration, but also in the distribution of particle components.

Risks for Population Health from Atmospheric Air Pollution in the City of Kazan

“…Our results enhance the existing evidence of the fact that atmospheric air pollution is a significant environmental risk factor for mortality and respiratory diseases [18][19][20][21]. A monitoring system available in large cities, insufficient account of atmospheric air pollutants prevent the correct assessment of the potential risk and actual damage for the population health.…”

A systematic review of cardiovascular emergency department visits, hospital admissions and mortality associated with ambient black carbon

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“…CTM is currently central to health effect analysis related to PM 2.5 components [109]. The disadvantages of CTM are: (1) the prediction effect was relatively low and variant among different regions.…”