The World Health Organization (WHO) has published a report entitled Key ingested per- and poly-fluoroalkyl substances (PFAS) and their health effects: landscape review that presents an overview of a comprehensive landscape review of PFAS. The authors assembled a health effects database comprising approximately 57,000 observations covering 66 individual PFAS, drawn from 48 distinct data sources. In parallel, the authors assembled an occurrence database containing nearly 300,000 observations across 77 PFAS from 49 data sources, focusing on media directly relevant to ingestion, such as drinking water, food, and human biomonitoring. As a key outcome of the landscape review, the report recommends prioritizing 18 PFAS and six health effect categories for further evaluation. The 18 PFAS include the 16 that were prioritized based on an evaluation of the occurrence data: perfluorooctanesulfonic acid (PFOS), perfluoroundecanoic acid (PFUnDA), perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluoroheptanesulfonic acid (PFHpS), perfluorobutanoic acid (PFBA), perfluorotridecanoic acid (PFTrDA), perfluorohexanoic acid (PFHxA), perfluorotetradecanoic acid (PFTeDA), perfluorobutanesulfonic acid (PFBS), perfluorohexanesulfonic acid (PFHxS), perfluoropentanoic acid (PFPeA/PFPA), perfluorododecanoic acid (PFDoA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), and perfluorodecanesulfonic acid (PFDS). The report notes that two additional compounds — trifluoroacetic acid and perfluoro(2-propoxypropanoic acid) — were also proposed for consideration, acknowledging the limitations of the literature search strategy, which was designed to include PFAS compounds and published studies that were included in the data sources. The report notes that if a compound such as trifluoroacetic acid was not considered a PFAS in the data sources or a compound such as perfluoro(2-propoxypropanoic acid) had unpublished studies, the literature search strategy may not have captured it. The six priority health effect categories are cancer, developmental, hepatic, immune, metabolic, and reproductive effects. According to the authors, the robust and transparent methodological framework used establishes a foundation for more detailed systematic evidence collection and review to support the derivation of health-based values.
