Multi-residue method for trace level determination of UV filters in fish based on pressurized liquid extraction and liquid chromatography-quadrupole-linear ion trap-mass spectrometry.

So far, the very few studies addressing the occurrence of UV filters (UV F) in biota showed important limitations in the analysis of the so complex biological matrices. In order to improve the knowledge on the bioaccumulation of UV F by fish, a simple and highly sensitive method was successfully developed and validated for the simultaneous determination of eight extensively used UV F and transformation products with a wide range of physicochemical properties. The present study demonstrated that liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) using a QqLIT mass analyser was applicable to the simultaneous analysis of UV F in fish. Pressurized liquid extraction (PLE) was chosen for the sample pretreatment due to the good extraction efficiency provided. An additional SPE clean-up step was added in order to minimize matrix effects and to improve the sensitivity. The method allowed recovery efficiencies in the range 70-112% for most compounds at the three spike levels. The low limits of detection (MLOD) achieved (0.1-6.0 ng/g dw) allowed the reliable quantification of UV F residues in fish samples. The developed methodology was applied to assess the occurrence of UV F in different fish species from the Guadalquivir river basin (Spain). Results confirmed the bioaccumulation of benzophenone-3 (BP3), ethylhexyl methoxycinnamate (EHMC) and octocrylene (OC) in the fish samples. The maximum concentration of 240 ng/g dw corresponded to EHMC, which was also the most ubiquitous compound. The reported concentrations constitute the first occurrence data of UV F residues in fish from Iberian rivers.