Nordic Working Paper Per- and polyfluoroalkylether substances: identity, production and use


The per- and polyfluoroalkyl substances (PFASs) are a class of chemicals of great concern today, due to their extreme persistence. The long-chain PFASs such as PFOS and PFOA (both perfluoroalkyl acids, or PFAAs) are known to be also bioaccumulative and toxic. Efforts have been made to phase out production and use of PFOS and PFOA in Europe and North America, and both PFOS and PFOA, together with their precursors, are now regulated globally under the Stockholm Convention. However, the chemical industry has developed many other PFASs, production of which continues. To date, some 4700+ monomeric and polymeric PFASs are identified as been on the global market, including many other than long-chain PFAAs and their precursors. This study focuses on one subset of PFASs, namely per- and polyfluoroalkylether substances (PFAEs). Many PFAEs are structurally similar to the rather well studied perfluoroalkyl acids (PFAAs) and their precursors, but with ether-linkage(s) between the perfluorocarbon moieties (e.g. – CnF2n–O–CmF2m–). A critical review found that due to structural similarities, many PFAEs have similar hazardous properties as PFAAs and their precursors1 . For example, perfluoroalkylether carboxylic acids (PFECAs) such as ADONA and GenX are similarly extremely persistent as PFOA, have high mobility in the environment, and can cause various toxicological adverse effects such as liver toxicity. Several PFECAs such as GenX and F-DIOX have been self-classified by their producers as “toxic” under REACH. Some current major producers of PFAAs and their precursors have also been the major producers of PFAEs since the 1970s2. In recent years, some of them have additionally marketed novel PFAEs as replacements to PFAAs and their precursors3 . However, in contrast to the well-studied PFAAs and their precursors, no clear overview of the production, import and use of all PFAEs is currently available in the public domain. While recent studies have focused on the two PFECAS RNw used as replacements to PFOA in fluoropolymer production, i.e. ADONA and GenX, many other PFAEs are being produced and used in a wide range of industrial and commercial applications without scrutiny. This lack of overview seriously hinders the efforts to understand, assess and manage these chemicals.

The full report can be accessed here.

Report prepared by Dr. Zhanyun Wang, Gretta Goldenman, Tugce Tugran, Alicia McNeil and Matthew Jones (Milieu Consulting) for Nordic Working Group on Chemicals, Environment and Health,January 2020