Per- and polyfluoroalkyl substances (PFASs) in drinking water: Current state of the science

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are ubiquitous emerging contaminants that have been used in many applications since the 1950s. They have been detected in many drinking water sources, sometimes at μg/L level in water impacted by point sources. Following growing concerns on adverse ecological and human health effects, in the early 2000s several countries established regulations on the PFASs of most concern. Fluorinated alternatives were consequently developed by manufacturers, resulting in the release of novel PFASs that have recently been detected in water resources. Like legacy PFASs, most of them are recalcitrant to conventional drinking water treatments. Governments face the challenge of defining guideline values for water often containing a mixture of several PFASs with little conclusive toxicological and epidemiological evidence. Around 3000 PFASs have been available on the global market, so the other key challenge is to identify the main ones in contaminated water resources, and to detect novel PFASs quicker than was the case for legacy PFASs.