A UHPLC-ESI-MS/MS method for the determination of ten phthalates in mineral water and olive oil samples was developed. A hold-back column placed between the pump and the injection valve allowed preventing the instrument background contamination by the phthalates. Good instrumental limits of detection (1-9 µg/L), precisions (RSD <23.9%), and trueness (relative error <20%) were achieved. A study of phthalate migration from PET bottles to mineral water at different domestic exposure conditions revealed that only diethyl phthalate migrated when exposed at 40 °C for six months, although at concentration levels below the method limit of quantitation. No matrix effect was found for mineral water samples and only dicyclohexyl phthalate was detected. Matrix-matched calibration was proposed for the analysis of olive oil samples due to the huge matrix effect encountered with the employed liquid-liquid extraction method. Among the olive oil samples where phthalates were detected, dibutyl phthalate was found only in one sample at the established EU specific migration level (0.3 mg/kg).
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