The Impact of Polycyclic Aromatic Hydrocarbons Exposure from Seasonal Biomass Burning on Oxidative Stress and Genotoxicity Biomarkers in Patients with Diabetes and Hypertension in Chiang Mai, Thailand
Polycyclic aromatic hydrocarbons (PAHs) are produced primarily by incomplete combustion of organic materials, including biomass burning, vehicle exhaust, and forest fires. Exposure to PAHs can induce reactive oxygen species (ROS) and oxidative stress, leading to lipid peroxidation and DNA damage. Biomass burning is a major environmental and public health problem in Chiang Mai province, containing particulate matter linked with respiratory and cardiovascular diseases. This prospective observational study aimed to evaluate the association between oxidative stress biomarkers and PAH exposure. A total of 152 participants comprised healthy controls (88), diabetes patients (35), hypertension patients (15) and diabetes + hypertension patients (14). Only participants aged more than 18 years were included. Participants who had acute respiratory infection or malignancies were excluded. This study was conducted in the pre-burning (December) and post-burning (May) periods by measuring biomarkers such as 1-OHP, MDA and 8-OHdG. Urinary 1-OHP increased significantly in the post-burning period from 0.21 ± 0.50 to 0.87 ± 1.25 μmol/mol creatinine (p < 0.001). Serum 8-OHdG increased significantly in all participants from 51.04 ± 24.90 to 66.08 ± 27.82 pg/mL (p < 0.001) and increased significantly in the diabetic and hypertension group. Serum MDA did not show any significant change post-burning (6.09 ± 3.71 to 6.00 ± 3.71 nmol/mL; p = 0.825), but MDA significantly decreased in the diabetic group (p = 0.017). 8-OHdG tended to increase in all clinical groups in the post-burning season compared to the pre-burning season, indicating oxidative DNA damage. 8-OHdG was found to be a sensitive biomarker of oxidative stress, suggesting its potential as an early indicator in haze season in vulnerable populations.