EC Commission staff working document Poly- and perfluoroalkyl substances (PFAS)
Poly-and perfluoroalkyl substances (PFAS) are a group of widely used man-made organic chemical substances. They contain alkyl groupson which all or many of the hydrogen atoms have been replaced with fluorine. Well known PFAS contain fully fluorinated carbon chainsof various chain lengths attached to a functional group, like carboxylic or sulfonic acids.
Such groups are called perfluorinated acids and include PFOA4and PFOS. Shorter chain PFAS have been developed more recently to substitute thelonger chain ones. In this context, an important distinction is the one between “long chain” and “short chain” PFAS6. The PFAS group includes also polymers: e.g. fluoropolymers, perfluoropolyethers8and side-chain fluorinated polymers. The OECD has published a clear explanation of the different groups of PFAS10. Examples of typical PFAS structures are shown.