Salivary 8-hydroxy-2'-deoxyguanosine as a biomarker of oxidative DNA damage in urban outdoor workers exposed to traffic-related air pollution.

Abstract

Urban air pollution, particularly fine particulate matter (PM2.5), is a major environmental health concern associated with oxidative DNA damage. However, evidence in occupationally exposed and socially vulnerable populations remains limited, and applicability of noninvasive biomarkers requires further investigation. The aim of this study was to determine feasibility of using salivary 8-hydroxy-2'-deoxyguanosine (8-OHdG) as a biomarker of oxidative DNA damage in urban workers exposed to traffic-related air pollution and examine this associations with environmental, biological, and socioeconomic variables. A cross-sectional study was conducted including outdoor street vendors compared to control indoor workers. Ambient PM2.5 concentrations and environmental noise levels were measured at workplaces using portable instruments. Salivary 8-OHdG concentrations were quantified by enzyme-linked immunosorbent assay (ELISA). Exposed workers exhibited significantly higher salivary 8-OHdG levels, indicating potential increased oxidative DNA damage. Positive associations were observed between 8-OHdG and PM2.5 levels, environmental noise, and body mass index (BMI), whereas income and education were correlated inversely. Multivariate models identified PM2.5 and BMI as independent predictors, and cluster analysis displayed consistent grouping of environmental and biological variables linked to oxidative stress. These findings demonstrate that occupational exposure to traffic-related air pollution may be associated with enhanced oxidative DNA damage in urban outdoor street vendors. Data support use of salivary 8-OHdG as a noninvasive biomarker for environmental biomonitoring. These results indicate an integrated role of environmental exposure, biological susceptibility, and socioeconomic vulnerability in urban air pollution, with implications for environmental health surveillance and public health interventions.