Per- and Polyfluoroalkyl substances (PFAS) are a class of fluorinated organic compounds known colloquially as “forever chemicals” because of their environmental persistence. A universally accepted PFAS definition does not currently exist. Various organizations, such as the U.S. Environmental Protection Agency (EPA) and the Organisation for Economic Co-operation and Development (OECD), are using different criteria.¹

In response to recent requests for PFAS compound coverage in our spectral libraries and specific databases, an EPA method was used in the determination. The current EPA PFAS substructure query (Figure 1) was used to identify potential PFAS compounds in Wiley's Spectral Libraries. Additional information regarding the current EPA PFAS substructure query can be found at the EPA CompTox Chemicals Dashboard: https://comptox.epa.gov/dashboard/chemical-lists/PFASSTRUCTV4

Figure 1. In Wiley's KnowItAll software² (ChemWindow application), the current 2021 EPA PFAS substructure query was drawn and searched (SearchIt application) against the KnowItAll reference libraries to identify potential PFAS compounds in each library. The resulting PFAS compound coverage is listed in Table 1 and Table 2 below.

Table 1. PFAS Compound Coverage in the KnowItAll Spectral Libraries.

Table 2. Additional PFAS Compound Coverage.

References

1. Williams AJ, Gaines LGT, Grulke CM, Lowe CN, Sinclair GFB, Samano V, Thillainadarajah I, Meyer B, Patlewicz G, and Richard AM (2022). Assembly and Curation of Lists of Per- and Polyfluoroalkyl Substances (PFAS) to Support Environmental Science Research. Front. Environ. Sci. 10:850019. doi: 10.3389/fenvs.2022.850019

2. KnowItAll Informatics System 2023, Analytical Edition. Copyright © 2001-2023 John Wiley & Sons, Inc. All Rights Reserved.

Acknowledgement

Special thanks to Antony Williams, Computational Chemist at The Center for Computational Toxicology & Exposure (CCTE) at the U.S. Environmental Protection Agency, for informative discussions regarding PFAS compounds.