The bioaccumulation and trophic magnification of certain perfluoroalkyl and polyfluoroalkyl substances (PFASs) are of increasing concern, including for human exposure which may predominately occur through the consumption of contaminated fish and seafood. Hitherto, legacy PFASs such as perfluorooctane sulfonate (PFOS) have garnered the most attention of biomonitoring surveys. Few studies, however, have focused on recently identified PFASs including short-chain perfluoroalkyl sulfonamides, fluorotelomer sulfonamidoalkyl betaines, and fluorotelomer betaines among others, signalling the need for a robust multi-analyte method. The lack of appropriate analytical standards and certified materials for these newly-identified PFASs has been an obvious limitation precluding estimation of the concentrations, but there exist other pitfalls. The pre-existing analytical methods were originally developed for the quantification of anionic and neutral PFASs, and may not be equally performant for many cationic and zwitterionic classes. The current research is focused on the development of a robust quantification method capable of encompassing a broad range of legacy and novel PFASs in aquatic species intended for human consumption, including tuna, salmon, shrimps, oysters, and mussels. In the initial stage of the optimization, various sample preparation approaches were compared for their extraction performance. Notably, ion pairing extraction and ultrasonication with basic methanol followed by solid-phase extraction, two prevailing methods in the PFAS literature, showed contrasted recovery performance for certain analytes. One further important issue to address was the possibility of signal alterations occurring at the analysis stage, the severity of which may vary according to matrix type and instrument technology. Mitigating such matrix effects through an appropriate clean-up and quantification strategy is essential to guarantee the accuracy performance, especially for those newly-identified PFASs due to the lack of matching internal standards. The retained method was validated in terms of linearity performance, limits of detection, and whole-method accuracy and precision, verified for distinct instrumental platforms involving liquid chromatography coupled to either tandem mass spectrometry (LC-MS/MS) or high-resolution Orbitrap mass spectrometry (LC-HRMS). The method was successfully applied to a selection of fish and seafood available to consumers in Eastern Canada.

Refining quantification strategies of per and polyfluoroalkyl substances in aquatic species: Toward a robust multi-analyte method

256th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.