Emerging pollutants in aquatic environments: monitoring of UV filters in urban wastewater treatment plants

Six UV filters - benzophenone-3 (BP-3), octocrylene (OC), ethylhexyl dimethyl p-aminobenzoate (OD-PABA), ethylhexyl methoxycinnamate (EHMC), ethylhexyl salicylate (EHS) and homosalate (HMS) - with endocrine disrupting potential were monitored in different wastewater treatment plants (WWTPs) located in Genoa, Italy. The influent and effluent samples were collected once a month from April to September 2011. The analytes were determined by stir bar sorptive extraction followed by liquid desorption (SBSE-LD) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Quantitative analysis was performed in triggered MRM (tMRM), which allowed improvement of specificity without compromising sensitivity. In the inlet samples four analytes were detected; in particular BP-3, OC, EHMC, and OD-PABA were in the range of 4-163, 12-390, 23-68, and 2-4 ng L-1, respectively. Measured concentrations indicated variability of UV filter inputs to WWTPs, with higher loads during the warmer months. A highly positive correlation was found between air temperature and the measured concentration of OC and BP-3. Only BP-3 and OC were detected in some effluent samples, with considerably lower concentrations. The removal efficiencies of the plants were in the range of 64 to >99% and 94 to >99% for BP-3 and OC, respectively.