5. Urban Runoffs as a Source of Emerging Micropollutants in Aquatic Environments

Freshwater ecosystems are continuously impacted by contaminants from urban runoff, a process that becomes more pronounced during rainfall events. This runoff originates from various urban surfaces, including roads, pavements, residential, industrial, and green areas, carrying a diverse array of micropollutants that pose a significant threat to surface water quality and aquatic ecosystem health. Climate change has further exacerbated these challenges by increasing the frequency and intensity of extreme weather events in urban areas. These conditions enhance the mobilization of pollutants through rainfall wash-off, leading to contamination levels that exceed normal conditions. Additionally, prolonged dry periods allow pollutants to accumulate on urban surfaces, which are then flushed into urban streams and water bodies during subsequent rainfall, further impacting biodiversity and water quality. To address these issues, we propose a comprehensive approach to assess the presence of micropollutants in urban runoff during extreme weather events. Our methodology employs liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS), integrating both target and suspect screening methods to identify and quantify a broad range of micropollutants. Understanding the composition of micropollutants in urban runoff is crucial for developing effective mitigation strategies. These findings will contribute to improved water management and the protection of freshwater ecosystems in the face of evolving climate conditions.