Is urinary 1-hydroxypyrene a valid biomarker for exposure to air pollution in outdoor workers? A meta-analysis

The aim of this study was to evaluate the usefulness and specificity of urinary 1-hydroxypyrene (1-OHPu) as a biomarker of the exposure from urban pollution to polycyclic aromatic hydrocarbons (PAHs) among outdoor workers in a meta-analysis. Our meta-analysis was performed according to standard methods, and the results show that the concentrations of 1-OHPu tend to be higher in exposed workers than in unexposed workers (if we exclude two highly heterogeneous articles), in exposed non-smokers than in unexposed non-smokers and in exposed than in unexposed workers who were carriers of the CYP1A1 genotype and in those with the glutathione-S-transferase M1 (-)genotype. These genotypes enhance the effect of exposure, particularly in non-smokers. Smoking reduces the differences between exposed and unexposed subjects. In conclusion, our results suggest that the use of the 1-OHPu biomarker appears to be reliable for studying occupational exposure to PAHs from urban pollution, as long as environmental and behavioural factors are considered.Journal of Exposure Science and Environmental Epidemiology advance online publication, 9 January 2013; doi:10.1038/jes.2012.111.