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Six UV filtersbenzophenone-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 À1 , 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.

A new, simple, and sensitive method was developed for extraction of ochratoxin A (OTA) in beer combined with HPLC-fluorescence detector. Samples were extracted by stir bar sorptive extraction (SBSE) followed by liquid desorption using commercially available Twister EG-Silicone. The main parameters influencing SBSE, including phase ratio, extraction time, stirring speed, ionic strength, organic modifier, pH, temperature, desorption mode, desorption solvent, and desorption time were optimized. Under the optimal conditions, assay was performed on 4 mL of samples acidified at pH 1.5. The samples were extracted for 180 min at a stirring speed of 800 rpm followed by desorption of analyte using 1 mL methanol under sonication for 45 min. The extract was evaporated at 50 degrees C under a gentle nitrogen stream, then redissolved in 200 microL of methanol-water (50 + 50, v/v). After each use, the stir bar was cleaned by sonication in methanol for 30 min three times. The method provided good linearity of the calibration curve with coefficients of determination greater than 0.999. Recoveries of OTA were greater than 83% with RSD lower than 10%, and LOD of OTA in beer was 0.64 ng/L. This method was applied to determine OTA in 19 beer samples. OTA was detected in 12 samples (63%) in the range of 0.01-0.27 ng/mL.

A rapid, simple, and reliable method using ultra-performance LC/MS/MS (UPLC/MS/MS) was developed for determination of ochratoxin A (OTA) in processed cereal products. OTA was ultrasonically extracted from the sample with acetonitrile-water (80 + 20, v/v), and the extract was then injected into the UPLC/MS/MS system after filtration. The calibration curves had good linearity with coefficients of determination greater than 0.999. Recoveries of OTA were in the range of 90-104%. LOD and LOQ of OTA in samples were 0.6 and 2.0 ng/g, respectively, and no significant matrix effect was found. This method was applied to determine OTA in 25 oat-based cereal samples. OTA was detected in five samples (20%) in the range of 2.4 to 7.3 ng/g.