REDS Environmental Consultancy has compiled an internal briefing note to upskill our team. In this article, we outline what PFAS are, where you find them, and the challenges arising in the assessment of PFAS.

What are PFAS?
  • Per and Polyfluoroalkyl Substances (PFAS) are man-made organic fluorides.
  • Hydrocarbons in which some (poly) or all (per) of the hydrogens have been replaced by fluorines.
  • Estimated to be ~6 million different compounds. The best known group are the PFAA (perfluoroalkyl acids), which includes PFOS and PFOA.
  • Airports – PFAA foam (AFFF*, hydraulic fluid, coolants)
  • Fire training facilities – AFFF
  • Major fire locations – AFFF
  • Waste water – Water discharge, biosolids, sludge to land
  • Industry – Manufacture of paper and cardboard, carpets, textiles, cosmetics, food packaging and chromium plating
  • Landfill – Short chain PFAS in leachates

*AFFF – Aqueous Film Foaming Foam

  • Ingestion of homegrown produce
  • Ingestion of soil and indoor dust
  • Inhalation / dermal contact
  • Drinking water ingestion
  • Background / ambient
  • Large number of compounds with different functional groups and therefore different behaviours.
  • Better studied compounds, PFOS/PFOA, cannot necessarily be used as proxies for other compounds.
  • Lack of, or conflicting, information on toxicological, physical, and chemical properties. Literature values can vary by several orders of magnitude.
  • Few published standards. Published standards vary.
  • Risk assessment models can be used to derive Generic Assessment Criteria (GAC), but model algorithms and results should be treated with caution.
  • Regulators likely to receive a wide range of bespoke assessments and GACs for consideration, increasing their work load.
  • Some GACs will be very low, potentially below laboratory Limit of Detection (LoD).
Our full PFAS briefing note is available as a download below.


For further information, contact our Environmental Consultancy team today.
0333 444 0004  /

Date Posted: 11/04/2024