Are humans and the environment exposed to increasing amounts of unknown highly fluorinated substances?

Per- and polyfluoroalkyl substances (PFASs) have been produced and used for over 50 years in various industrial and commercial applications. Recent decline in human levels of PFOS and PFOA might be a result of national and international regulations and voluntarily phase-outs. Our recent study however indicates an increase in unidentified organofluorine (OF). It is unclear whether the overall human and environmental exposure to OF has declined or if evidence suggest a shifted contamination to unknown PFASs. In this project, human blood and sewage samples collected from different countries will be analyzed for total OF (TOF) and PFASs using combustion ion chromatography (TOF-CIC) to answer the following questions: what is the current human exposure to unidentified PFASs; how much are released into the environment; do unidentified PFASs and their sources vary regionally and globally; and what are these unknown PFASs.