Oxidative damage to DNA and lipids as biomarkers of exposure to air pollution.
BACKGROUND
Air pollution is thought to exert health effects through oxidative stress, which causes damage to DNA and lipids.


OBJECTIVE
We determined whether levels of oxidatively damaged DNA and lipid peroxidation products in cells or bodily fluids from humans are useful biomarkers of biologically effective dose in studies of the health effects of exposure to particulate matter (PM) from combustion processes.


METHODS
We identified publications that reported estimated associations between environmental exposure to PM and oxidative damage to DNA and lipids in PubMed and EMBASE. We also identified publications from reference lists and articles cited in the Web of Science.


METHODS
For each study, we obtained information on the estimated effect size to calculate the standardized mean difference (unitless) and determined the potential for errors in exposure assessment and analysis of each of the biomarkers, for total and stratified formal meta-analyses.


RESULTS
In the meta-analysis, the standardized mean differences (95% confidence interval) between exposed and unexposed subjects for oxidized DNA and lipids were 0.53 (0.29-0.76) and 0.73 (0.18-1.28) in blood and 0.52 (0.22-0.82) and 0.49 (0.01-0.97) in urine, respectively. The standardized mean difference for oxidized lipids was 0.64 (0.07-1.21) in the airways. Restricting analyses to studies unlikely to have substantial biomarker or exposure measurement error, studies likely to have biomarker and/or exposure error, or studies likely to have both sources of error resulted in standardized mean differences of 0.55 (0.19-0.90), 0.66 (0.37-0.95), and 0.65 (0.34-0.96), respectively.


CONCLUSIONS
Exposure to combustion particles is consistenly associated with oxidatively damaged DNA and lipids in humans, suggesting that it is possible to use these measurements as biomarkers of biologically effective dose.
Møller
Peter
P
Department of Public Health, Section of Environment Health, University of Copenhagen, Copenhagen, Denmark. pemo@sund.ku.dk
Loft
Steffen
S
D000393:Air Pollutants / Q000633:toxicity*; D015415:Biomarkers / Q000032:analysis; D003430:Cross-Sectional Studies; D004249:DNA Damage; D004781:Environmental Exposure; D006801:Humans; D050356:Lipid Metabolism / Q000187:drug effects*; D018384:Oxidative Stress / Q000187:drug effects*
D000393:Air Pollutants; D015415:Biomarkers