Global occurrence and aquatic hazards of antipsychotics in sewage influents, effluent discharges and surface waters

Despite increasing reports of pharmaceuticals in surface waters, aquatic hazard information remains limited for many contaminants, particularly for sublethal, chronic responses plausibly linked to molecular initiation events that are largely conserved across vertebrates. Here, we critically examined available refereed information on the occurrence of 67 antipsychotics in wastewater effluent and surface waters. Because the majority of sewage remains untreated around the world, we also examined occurrence in sewage influents. When sufficient information was available, we developed probabilistic environmental exposure distributions (EEDs) for each compound in each matrix by geographic region. We then performed probabilistic environmental hazard assessments (PEHAs) using therapeutic hazard values (THVs) of each compound, due to limited sublethal aquatic toxicology information for this class of pharmaceuticals. From these PEHAs, we determined predicted exceedances of the respective THVs for each chemical among matrices and regions, noting that THV values of antipsychotic contaminants are typically lower than other classes of human pharmaceuticals. Diverse exceedances were observed, and these aquatic hazards varied by compound, matrix and geographic region. In wastewater effluent discharges and surface waters, sulpiride was the most detected antipsychotic; however, percent exceedances of the THV were minimal (0.6%) for this medication. In contrast, we observed elevated aquatic hazards for chlorpromazine (30.5%), aripiprazole (37.5%), and perphenazine (68.7%) in effluent discharges, and for chlorprothixene (35.4%) and flupentixol (98.8%) in surface waters. Elevated aquatic hazards for relatively understudied antipsychotics were identified, which highlight important data gaps for future environmental chemistry and toxicology research.