Ren, C; Fang, S; Wright, RO; Suh, H; Schwartz, J
Background: Studies show that exposure to air pollution damages human health, but the mechanisms are not fully understood. One suggested pathway is via oxidative stress.
Objectives: This study examines associations between exposure to air pollution and oxidative DNA damage, as indicated by urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG) concentrations in ageing participants during 2006–2008.
Methods: We fit linear regression models to examine associations between air pollutants and 8-OHdG adjusting for potential confounders.
Results: 8-OHdG was significantly associated with ambient particulate matter ≤2.5 μm in aerodynamic diameter (PM2.5), nitrogen dioxide (NO2), maximal 1 h ozone (O3), sulphate (SO42−) and organic carbon (OC), but not with black carbon (BC), carbon monoxide (CO), the number of particles (PN) or elemental carbon (EC). Effects were more apparent with multi-week averages of exposures. Per IQR increases in 21-day averages of PM2.5, PN, BC, EC, OC, CO, SO42−, NO2 and maximal 1 h O3 were associated with 30.8% (95% CI 9.3% to 52.2%), −13.1% (95% CI −41.7% to 15.5%), 3.0% (95% CI −19.8% to 25.8%), 5.3% (95% CI −23.6% to 34.2%), 24.4% (95% CI 1.8% to 47.1%), −2.0% (95% CI −12.4% to 8.3%), 29.8% (95% CI 6.3% to 53.3%), 32.2% (95% CI 7.4% to 56.9%) and 47.7% (95% CI 3.6% to 91.7%) changes in 8-OHdG, respectively.
Conclusions: This study suggests that ageing participants experienced an increased risk of developing oxidative DNA injury after exposure to secondary, but not primary, ambient pollutants.
