Air Pollutants and Incidence of All-Cause, Lung, and Bladder Cancer in the Gazel Cohort (1989-2014)

Abstract

Background/AimWhile air pollutants – fine particulate matter (PM2.5), nitrogen dioxide (NO2), ozone (O3) and black carbon (BC) – are associated with mortality, their association with cancer incidence remains unclear. We aimed to analyze the relationships between these pollutants and the incidence of all-cause, lung and bladder cancer in the French general population-based cohort Gazel.MethodsLand use regression models with back-extrapolation were used to assess the long-term exposure to PM2.5, NO2, O3 and BC at home addresses of 19,530 participants, as the average exposure between enrolment and cancer incidence or censoring, whichever came first, with a 10-year lag to account for the time between initial exposure and the development of cancer. Follow-up was from 1989 to 2014. We used Cox models to derive hazard ratios (HR) for an interquartile range (IQR) increase of single pollutant exposure, adjusted for lifestyle and socioeconomic individual covariables at baseline including gender and occupational exposures, and with age as the underlying time scale.ResultsWe found significant associations between PM2.5 (IQR 7 µg/m3) and incident all-cause and lung cancer with respective HR of 1.15 (CI 1.10-1.21) and 2.08 (1.76-2.45); between NO2 (IQR 21 µg/m3) and all-cause and lung cancer with respective HR of 1.05 (1.01-1.10) and 1.32 (1.11-1.57); between BC (IQR 1 µg/m3) and all-cause and lung cancer with respective HR of 1.05 (1.01-1.09) and 1.43 (1.23-1.66). No significant association was found between O3 and incident cancers, nor between any pollutant and bladder cancer .ConclusionsPM2.5, NO2 and BC are associated with incidence of all-cause and specifically lung cancer in a general population-based cohort.