Article Text

Download PDFPDF
Urinary 8-hydroxy-2′-deoxyguanosine as a biomarker of oxidative DNA damage induced by ambient pollution in the Normative Aging Study
  1. Cizao Ren1,
  2. Shona Fang2,
  3. Robert O Wright3,4,
  4. Helen Suh1,
  5. Joel Schwartz1
  1. 1Department of Environmental Health, Exposure, Epidemiology and Risk Program, Harvard School of Public Health, Boston, Massachusetts, USA
  2. 2Environmental and Occupational Medicine and Epidemiology Program, Harvard School of Public Health, Boston, Massachusetts, USA
  3. 3Department of Pediatrics, Children's Hospital, Boston, Massachusetts, USA
  4. 4Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA
  1. Correspondence to Cizao Ren, Department of Environmental Health, Exposure, Epidemiology and Risk Program, Harvard School of Public Health, Landmark Center, West, Suite 415, PO Box 15677, 401 Park Dr., Boston, MA 02215, USA; rencizao{at}


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

Statistics from


  • Funding This work was supported by National Institute of Environmental Health Sciences grants ES014663, ES 15172 and ES-00002, by US Environmental Protection Agency grant R832416 and USDA Contract 58-1950-7-707. The Normative Aging Study is supported by the Cooperative Studies Program/Epidemiology Research and Information Center of the US Department of Veterans Affairs, and is a component of the Massachusetts Veterans Epidemiology Research and Information Center. It is partially supported by Harvard-NIOSH ERC Pilot (T42 OH008416).

  • Competing interests None.

  • Ethics approval This study was conducted with the approval of the Harvard School of Public Health.

  • Provenance and peer review Not commissioned; externally peer reviewed.

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.