Simultaneous determination of 16 organophosphorus flame retardants and plasticizers in fish by liquid chromatography-tandem mass spectrometry

• A simultaneous determination of sixteen OPFRs in biota was successfully achieved by LC–MS–MS.
• Thirteen out of sixteen OPFRs were detected in barbel, trout and carp samples collected on a Spanish river.
• IPPP and IDPP were found for the first time in biota samples and at high concentration levels.

In this work a method to analyze simultaneously sixteen organophosphorus flame retardants (OPFRs) by liquid chromatography-quadrupole-linear ion trap mass spectrometry (LC-QqLIT-MS) in fish samples was successfully developed. Sample preparation strategies, including different extraction techniques and clean-ups were tested. The chosen methodology is based on the extraction of 0.25 g of dried fish by ultrasound and clean-up by solid phase extraction (SPE) with a tandem of C18 and basic alumina cartridges. Recoveries were between 45 to 115%, with RSDs lower than 25%. mLODs and mLOQs were between 0.34–11.6 ng/g lw and 1.12–38.8 ng/g lw, respectively, with the exception of Tris(tribromoneopentyl)phosphate (TBNPP) (37.4 and 125 ng/g lw, respectively) and Tris(isopropyl-phenyl)phosphate (IPPP) (51.6 and 172 ng/g lw, respectively) which had higher limits. The developed method was applied to twelve river fish samples. Thirteen out of sixteen analyzed compounds were detected. At least, one of the sixteen studied OPFRs was detected in all the analyzed samples, with ΣOPFR levels up to 2423 ng/g lw. This is the first study reporting IPPP and Isodecyldiphenyl phosphate (IDPP) levels in biota samples. Moreover, levels found for IPPP are quite high (up to 601 ng/g lw) and thus it is important to consider in the future development of analytical methodologies for OPFR analysis.