Long term exposure to air pollution and kidney parenchyma cancer – Effects of Low-level Air Pollution: a Study in Europe (ELAPSE)

Abstract

BACKGROUND AND AIM: Particulate matter (PM) is classified as a group 1 human carcinogen. Previous experimental studies suggest that particles in diesel exhaust induce oxidative stress, inflammation and DNA damage in kidney cells, but the evidence from population studies linking air pollution to kidney cancer is limited. METHODS: We included six cohorts from the "Effects of low level air pollution: A study in Europe” (ELAPSE) collaboration. We developed hybrid models combining monitoring and land use data, satellite observations, and dispersion model estimates for nitrogen dioxide (NO2), fine PM (PM2.5), black carbon (BC), warm season ozone (O3), and eight elemental components of PM2.5 (copper, iron, potassium, nickel, sulfur, silicon, vanadium, and zinc) to assign exposure to participants’ residential addresses. We defined kidney parenchyma cancer according to the International Classification of Diseases 10th and 9th Revision codes C64 and 189.0. We applied Cox proportional hazard models adjusting for potential confounders at the individual and area-level. RESULTS: A total of 302,493 persons were included in the analyses. During a total of 5,497,514 person-years of follow-up (mean 18.2 years), 847 incident cases of kidney parenchyma cancer occurred. Median (5–95%) exposure levels of NO2, PM2.5, BC and O3 were 24.1 µg/m3 (12.8–39.2), 15.3 µg/m3 (8.6–19.2), 1.6 10-5/m (0.7–2.1), and 87.0 µg/m3 (70.3–97.4), respectively. The results of the fully adjusted linear analyses showed a hazard ratio (95% confidence interval) of 1.03 (0.92, 1.15) per 10 μg/m³ NO2, 1.04 (0.88, 1.21) per 5 μg/m³ PM2.5, 0.99 (0.89, 1.11) per 0.5 10−5m−1 BC, and 0.88 (0.76, 1.02) per 10 μg/m³ O3. The analyses did not show associations between any of the elemental components of PM2.5 and cancer of the kidney parenchyma. CONCLUSION: We did not observe evidence of an association between long-term ambient air pollution exposure and incidence of kidney parenchyma cancer.