Determination and risk assessment of UV filters and benzotriazole UV stabilizers in wastewater from a wastewater treatment plant in Lüneburg, Germany.

UV filters and benzotriazole UV stabilizers are considered emerging contaminants in the environment. LC-MS/MS and GC-MS methods, involving a single solid phase extraction protocol, were developed and validated to determine eight UV filters and seven UV stabilizers, respectively in wastewater from a wastewater treatment plant (WWTP) in Lüneburg, Germany. The LC-MS/MS method exhibited extraction recoveries of ≥ 71% at six different fortification levels with limits of detection (LODs) range of 0.02 ng mL^-1 - 0.09 ng mL^-1. Extraction recoveries of 47 to 119% at six different fortification levels were obtained for the GC-MS method with LODs range of 0.01 - 0.09 ng mL^-1. Among the UV filters, the highest mean concentration was determined for octocrylene (OCR) in influent (3.49 ng mL^-1) while the highest mean concentration was measured for 2-hydroxy-4-octyloxybenzophenone (UV 531) in influent (0.44 ng mL^-1) among the UV stabilizers. Potential risk to aquatic organisms was assessed by the risk quotient approach. Only OCR presented a high risk to aquatic invertebrates whereas 2-ethylhexyl 4-methoxycinnamate (EHMC) and 2-ethylhexyl salicylate (EHS) posed high risks to algae. Benzotriazole UV stabilizers presented negligible risks to aquatic invertebrates and fish. This work reports the detection of rarely studied 4-aminobenzoic acid (PABA) and UV 531 in WWTP influent and effluent. The occurrence and risk assessment of target benzotriazole UV stabilizers in wastewater from a German WWTP was demonstrated for the first time.