Wildfire erosion as a pathway for endocrine disrupting chemical contamination in watersheds: a scoping review

Hannah Fitzhugh^*Marcos D. Mateus

• Instituto Superior Tecnico - Universidade de Lisboa, Lisboa, Portugal

Synthetic endocrine disrupting chemicals (EDCs) are pervasive micropollutants found in aquatic, terrestrial, and anthropogenic systems that cause irreversible damage to human and wildlife hormonal function. Although research is underway to monitor EDCs in water, the effect of wildfire erosion on EDC contamination in watersheds is underexplored. Wildfires modify soil and vegetation properties, often leading to increased erosion and sediment, especially following rainfall. Some synthetic EDCs that are known to persist in watersheds are heat-resistant and mobile, such as polybrominated diphenyl ethers (PBDE), per- and perfluoroalkyl substances (PFAS), and polychlorinated biphenyls (PCBs). Wildfires have the potential to transport and concentrate EDCs from terrestrial environments into the aquatic systems via post-fire runoff. In this paper, we propose that wildfire erosion contributes to increased EDC contamination within watersheds, thereby posing a cumulative and significant threat to water quality. We identify critical gaps in current literature and propose a targeted EDC water quality monitoring panel that can be deployed post-wildfire for early detection and response. Finally, we outline key research opportunities to advance understanding of EDC behavior in post-fire landscapes. We aim to alert water quality monitoring professionals to this underrecognized hazard and to highlight the urgent need for focused research on its implications for both public and environmental health.