Article Text
Abstract
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.
- 8-Hydroxy-2'-deoxyguanosine
- air pollution
- DNA damage
- oxidative stress
- biomarker
- epidemiology
- public health