EVALUATION OF OXIDATIVE STRESS BIOMARKER LEVELS IN FIREFIGHTERS EXPOSED TO FOREST FIRES IN THE PANTANAL/MT REGION

Resumo

INTRODUCTION: Climate change has intensified extreme events such as heat waves, droughts, and wildfires. The Brazilian Pantanal is increasingly threatened by economic activities including fishing, livestock farming, and deforestation. The use of fire as a land management practice is common in this region and increases the risk of large-scale forest fires, leading to the release of substantial amounts of greenhouse gases and particulate matter. Fire control workers are exposed to high temperatures and elevated concentrations of toxic compounds, which can cause severe adverse health effects. Biomarkers of oxidative stress are sensitive indicators of early biological damage that may progress to more serious health conditions. OBJECTIVE: To evaluate serum levels of oxidative stress biomarkers, including malondialdehyde (MDA), protein carbonyls (PC), superoxide dismutase (SOD), and total antioxidant capacity (CAOT), in workers exposed to smoke from forest fires in the Pantanal region of Mato Grosso, Brazil. MATERIALS AND METHODS: Blood samples were collected from 239 firefighting workers, including individuals in training courses (CFO) and those directly involved in field activities, namely firefighters and brigadistas, between May and October 2023. Analyses were performed using a microplate reader with UV–Vis spectrophotometry. Statistical analyses were conducted using GraphPad Prism 8. RESULTS AND CONCLUSION: Data were grouped according to worker category (CFO, firefighters, and brigadistas) and compared between the exposure period and post-exposure period (Phases 1 and 2). Although variations were observed among biomarkers and groups, workers in training courses (CFO) generally exhibited lower levels of oxidative stress. Firefighters showed no statistically significant differences between Phases 1 and 2, whereas brigadistas presented greater oxidative damage during the exposure phase. These findings suggest that the personal protective equipment used by firefighters provides more effective protection against toxic smoke and its harmful health effects, unlike the equipment available to brigadistas, who experienced higher oxidative damage. This redox imbalance may exacerbate chronic lung diseases and increase susceptibility to respiratory infections, highlighting the relevance of oxidative stress biomarkers in improving disease prognosis in populations exposed to air pollution.