About PFAS

Key PFAS concepts

What is PFAS?

Per- and polyfluoroalkyl substances (PFAS, sometimes also spelled PFASs) are a group of 5,000 to 10,000 organic chemicals commonly used in numerous industrial and commercial applications worldwide. They are exclusively synthetic and were first created by accident in the 1930s. PFAS have been commercially produced since the 1950s.

PFAS are water and oil repellent which makes them useful for protecting surfaces from damage and staining. The best-known applications of PFAS are the non-stick coating Teflon and the fabric protector Scotchguard. In addition, PFAS are very heat-resistant, making them the ideal ingredients for fire-fighting foams.

One of the downsides of PFAS are their extreme persistence and widespread distribution in the environment, which have earned them their reputation as ‘forever chemicals’. Consequently, PFAS accumulate in the environment and living organisms. The longer an organism lives and the higher up in the food chain it is positioned, the more PFAS it may acquire over the course of its life.

PFAS easily bind to the proteins in blood and muscles. Almost all people, even in the remotest of communities, carry a certain level of PFAS in their bloodstream. As the bonds between PFAS and proteins are very stable, the chemicals can remain in the body for several years.

We commonly ingest PFAS via food or water. Seafood is one of the most highly polluted sources of PFAS. Since the 2010s numerous studies have provided evidence for a link between PFAS exposure and a range of medical conditions in humans and animals. PFAS exposure can increase the risk of kidney and testicular cancer, reduced birth weight and high cholesterol levels.

Long-chained vs. short-chained PFAS

The term ‘long-chained’ generally refers to PFAS with eight or more carbon atoms. However, it mostly refers to PFOS (Perfluorooctane sulfonic acid) and PFOA (Perfluorooctanoic acid), which are historically the most commonly produced, most studied and most widely distributed PFAS worldwide. PFOS was used as the key ingredient of Scotchgard. Furthermore, PFOS and PFOA were both crucial components of fire-fighting foams. Generally, the longer the carbon chain, the more resistant the type of PFAS is in the environment and the body.

Phasing out PFOA and PFOS

In the 2010/2015 PFOA Stewardship Program, a US government agency negotiated (EPA) and agreed with eight companies, the main producers of PFAS worldwide, upon eliminating PFOA from any production processes by 2015. In the UN-initiative, the Stockholm Convention on Persistent Organic Pollutants (POPs), 152 signatories agreed to eliminate PFOA by 2019. Furthermore, the Stockholm Convention obliged their members to severely limit the use of PFOS to certain purposes. Another PFAS type, PFHxS (6C), has recently been proposed to be added to the list of restricted chemicals.

Since restrictions have increasingly been put in place, the PFAS producers started developing a new generation of PFAS with usually shorter carbon chain length, including PFBS (4C) and GenX (6C). Instead of a general reduction of use, there is an ongoing shift to new and shorter PFAS types. Studies on the harmfulness of new chemicals take time, and hence, we yet have to explore the environmental and health effects of those new PFAS.

Listen to some more PFAS facts and learn how PFAS affects polar bears in the Arctic:

Our team member Cat Vendl interviewed Dr Heli Routti, a toxicologist from the Norwegian Polar Institute in Tromsø, about her work on PFAS in Arctic wildlife. Heli talks about the challenges of sampling dangerous wildlife like polar bears. She also explains how PFAS has ended up in the most remote of places like in the Arctic and talks about the potential health consequences of high PFAS burdens in the polar bears’ bodies. Heli and her colleagues found that polar bears carry PFAS burdens as high as those in people who work at a PFAS plant.

The interview was part of the weekly science radio show and podcast, Boiling Point (@BoilingPointFM).

Tune in here or here!