A pilot study on human exposure to novel poly- and perfluoroalkyl substance (PFAS) and its alternatives and total extractable organofluorine (TOF) in Sweden

Human blood is an important matrix to assess human exposure to poly- and perfluoroalkyl substance (PFASs), as these compounds have been shown to preferentially accumulate in protein-rich sites such as blood and liver. A number of PFAS biomonitoring studies used blood (whole blood, serum, or plasma) as sample matrices. Recent studies used the concept of mass balance analysis of fluorine by comparing the levels of quantifiable (known) PFASs quantified through liquid chromatography tandem mass spectrometry (LC-MS/MS) and the levels of total extractable organofluorine (EOF) measured via combustion ion chromatography (CIC); or in other words, how much unknown PFASs was in the sample. These unidentified PFASs might be those unrecognized intermediates, ultrashort- chain PFAS compounds (compounds having 2 to 3 perfluorinated chain length), and/or novel PFAS alternatives. In this project, human blood will be collected from different parts of Sweden and analyzed for EOF, conventional PFASs, and some identified PFAS alternatives in order to assess current status of human exposure to PFAS.