Long-term Ambient Fine Participate Matter Air Pollution and Lung Cancer in a Large Cohort of Never-Smokers

摘要

Rationale: There is compelling evidence that acute and chronic exposure to ambient fine particulate matter (PM_(2.5)) air pollution increases cardiopulmonary mortality. However, the role of PM_(2.5) in the etiology of lung cancer is less clear, particularly at concentrations that prevail in developed countries and in never-smokers. Objectives: This study examined the association between mean long-term ambient PM_(2.5) concentrations and lung cancer mortality among 188,699 lifelong never-smokers drawn from the nearly 1.2 million Cancer Prevention Study-ll participants enrolled by the American Cancer Society in 1982 and followed prospectively through 2008. Methods: Mean metropolitan statistical area PM_(2.5) concentrations were determined for each participant based on central monitoring data. Cox proportional hazards regression models were used to estimate multivariate adjusted hazard ratios and 95% confidence intervals for lung cancer mortality in relation to PM_(2.5). Measurements and Main Results: A total of 1,100 lung cancer deaths were observed during the 26-year follow-up period. Each 10 ng/m~3 increase in PM_(2.5) concentrations was associated with a 15-27% increase in lung cancer mortality. The association between PM_(2.5) and lung cancer mortality was similar in men and women and across categories of attained age and educational attainment, but was stronger in those with a normal body mass index and a history of chronic lung disease at enrollment (P < 0.05). Conclusions: The present findings strengthen the evidence that ambient concentrations of PM_(2.5) measured in recent decades are associated with small but measurable increases in lung cancer mortality.