Health risk assessment in atmosphere near a petrochemical industrial complex: Measuring oxidative potential and oxidative burden

Particulate matter (PM) contributes substantially to the hazards associated with air pollution. Oxidative potential (OP) and oxidative burden (OB) can be useful to assess health risk. The population living in the area surrounding an industrial complex in the Metropolitan Area of São Paulo (Brazil) has exhibited higher frequencies of health impacts, such as thyroid diseases, which highlighted the authors' attention. In the present study, total suspended particles (TSP) and fine PM (PM2.5) were collected between 2015 and 2018. Then, OP and OB related to PM exposure at this industrial complex neighborhood were determined, using methods which measure the oxidation of lung antioxidants, glutathione (GHS), and ascorbic acid (AA), and reactive oxygen species (ROS) production by dithiothreitol (DTT) assay. TSP samples (2015 mean = 49 ± 21 μg m−3) showed higher concentrations than PM2.5 (2018 mean = 32 ± 18 μg m−3). PM2.5 campaigns presented high OP and OB for ascorbate (AA), and glutathione (GSH), while OP and OB for dithiothreitol (DTT) was higher in TSP. There were associations between OPAA and PM, for both TSP and PM2.5. However, no positive associations were found between PM and OBGSH and OBDTT indicating that in this context PM concentration did not necessarily reflect the health risk of exposure. The air masses trajectories indicated influences from industrial, vehicular emissions over the years. In conclusion, OP results may reveal critical health risks better than PM mass at this industrial complex region.