Oxidative Stress Associated with Chronic Occupational Exposure to Petroleum Hydrocarbons among Gas Station Attendants in Gampaha District, Sri Lanka

Abstract

BACKGROUND: Gas station attendants (GSA) are at risk of adverse health outcomes due to chronic occupational exposure to petroleum hydrocarbons and poor occupational safety practices. In Sri Lanka, extended working hours, minimal use of personal protective equipment (PPE), and limited health surveillance exacerbate these risks. This study aimed to evaluate oxidative stress biomarkers and associated health risks among GSA in the Gampaha District. METHODS: A cross-sectional study was conducted among 25 exposed workers and 25 age-matched unexposed controls. Data on sociodemographic characteristics, occupational exposure history, lifestyle factors, and self-reported health symptoms were collected using a structured questionnaire. Blood samples were analyzed for oxidative stress biomarkers, including glutathione (GSH), 8-hydroxydeoxyguanosine (8-OHdG), and total antioxidant capacity (TAC), using enzyme-linked immunosorbent assay (ELISA). RESULTS: GSH levels were significantly higher among GSA (p = 0.043), indicating a potential early-phase compensatory antioxidant response to chronic petroleum vapor exposure. However, no statistically significant differences were found in TAC (p = 0.101) or 8-OHdG (p = 0.770) between exposed and control groups. Self-reported symptoms such as headaches, fatigue, memory disturbances, and respiratory complaints were more prevalent among the GSA. Alarmingly, PPE usage was extremely limited, with only 4% reporting access to masks and none to gloves, indicating a critical gap in occupational health protection. CONCLUSION: The findings indicate early biochemical signs of oxidative stress among gas station attendees, alongside poor adherence to occupational safety practices. Immediate implementation of regulatory interventions, including mandatory PPE provision and health education, is essential to reduce long-term health risks in this vulnerable workforce.