Application of effect-directed methods and suspect screening strategies for an integrated assessment and prioritization of organic contaminants in aqueous samples

Abstract

Owing to the vast amount of organic contaminants detected in environmental water bodies, there is an increasing demand on detecting those compounds that pose a real risk for the environmental ecosystem. The use of high-resolution chemical analysis to detect unknown compounds in combination with ERA studies and in vivo/in vitro bioassays is an effective way to prioritize potential toxicants. In this sense, we carried out the development and validation of multitarget and suspect screening methods to identify simultaneously different CECs (both, known and unknown) in complex environmental aqueous matrixes. Considering that urban WWTPs have been described as one of the main pathways for CECs into aquatic ecosystems, we assessed the efficiency of different secondary treatments to remove organic micropollutants. The use of an ERA strategy allowed the elucidation and prioritization of toxicologically relevant compounds released into the aquatic system. Moreover, a more holistic approach known as effect-directed analysis (EDA), which combines chemical and biological analyses to unravel cause-effect relationships, was applied to identify toxicity drivers in hospital effluents. In this case two different bioassays were used in EDA to assess different environmental endpoints: (i) the in vitro yeast estrogen bioassay (YES) to measure estrogenic activity and (ii) the in vivo sea urchin embryo test (SET) to evaluate apical effects.