Natural cause mortality and exposure to elemental composition of particulate matter: an analysis of 19 European cohorts within the multi-center ESCAPE project

摘要

Background Studies have shown associations between mortality and long-term exposure to particle mass air pollution. Studies on the effects of the elemental composition of particulate matter are, however, limited. Aims To study the association between natural cause mortality and long-term exposure to the elemental composition of particulate matter within the multi-center European Study of Cohorts for Air Pollution Effects (ESCAPE) project and the Transport related Air Pollution and Health impacts (TRANSPHORM) project. Methods Data from 19 European cohort studies were used. Residential exposure was characterized following a strictly standardized protocol as annual average concentrations of Copper (Cu), Iron (Fe), Potassium (K), Nickel (Ni), Sulphur (S), Silicon, (Si), Vanadium (V) and Zinc (Zn) within PM size fractions ＜2.5μm (PM2.5) and ＜10μm (PM10), estimated using land-use regression (LUR) models. Cohort-specific statistical analyses of the associations between mortality and air pollution were conducted using Cox proportional hazards models using a common protocol followed by meta-analysis. Results The total study population consisted of 322,159 participants, of which 27,208 died from a natural cause during follow-up. Elevated risks were shown for all elements with significantly elevated hazard ratios for: S PM2.5 (1.15 (95% CI: 1.06-1.25) per 200 ng/m3); Si PM2.5 (1.09 (95% CI: 1.01-1.18) per 100 ng/m3); and Ni PM10 (1.10 (95% CI: 1.01-1.21) per 2 ng/m3). No heterogeneity between individual cohort effect estimates was found for these significant associations. Conclusions Long-term exposure to elemental composition of particulate matter was associated with natural cause mortality.