Quantification of target per- and polyfluoroalkyl substances (PFASs) and extractable organic fluorine (EOF) in crayfish from Lake Vättern, Sweden.

Abstract: Per- and polyfluorinated substances (PFASs) are a family of persistent organic pollutants in which the aliphatic carbon chains have been fluorinated, either completely or partially. One subclass of PFASs are perfluoroalkyl acids (PFAAs), in which perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkyl sulfonic acids (PFSAs) are two prominent groups. PFASs are toxic to the environment, as well as humans, and are found to have a developmental, neurological and immunological toxicity. They are also found to be possibly carcinogenic. In this study, the quantity of target PFASs was determined in 11 samples of hepatopancreas in crayfish from different locations in Lake Vättern, Sweden, using liquid chromatography coupled to tandem mass spectrometry. The hepatopancreas is the crayfish detoxification organ and therefore, it is also where persistent organic pollutants are possibly accumulated. Extractable organic fluorine concentration was also determined, using combustion ion chromatography to account for other fluorinated compounds not included in the target analysis of 31 PFASs. The amount of target PFASs was compared to the extractable organic fluorine concentration, giving an idea of how much of the extractable organic fluorine that consists of identified PFASs in relation to unidentified organic fluorine.  The measured concentrations of target PFASs were compared to measured concentrations in a previous study (2008) of PFASs in the hepatopancreas of crayfish from two different locations in Lake Vättern. Concentrations of the measured target PFASs were also related to if the sampling sites for each pooled sample was located close to a known point source, Karlsborg military airport. A sum of the average of PFHxS, PFOS, PFOA and PFNA for all sample sites were compared to a combined tolerable weekly intake (TWI) for these four compounds, established by the European Food Safety Authority (EFSA). As well as the intake of PFOS and PFOA compared individually against their TWI.