Per- and polyfluoroalkyl substances (PFAS) are a group of man-made compounds that have been manufactured since the 1940s to act as water repellents and to serve a variety of functions in industry. The class of compounds, due to their strong C-F bonds, are very persistent in the environment and can accumulate in the human body over long periods from consistent exposure to very small concentrations. There is evidence that exposure to PFAS can lead to adverse human health effects.

Here are the highlights from the 2020 review paper, Scientific Basis for Managing PFAS as a Chemical Class.

(1) the authors provide “scientific justification for why a class-based
approach is appropriate
and necessary for all PFAS, defined as
chemicals with at least one aliphatic perfluorocarbon moiety
(e.g., -CnF2n-).”

(2)”Limited testing of primarily large public water sources in the US found PFAS in the water supplies serving an estimated 16.5 million people,
including 6 million with a combined PFOS and PFOA
concentration over the US EPA’s lifetime health advisory of 70

(3) “New analytical methods allow for more comprehensive
screening such as measuring total extractable/adsorbable organofluorine in the environment, products, dust, biota and humans. These methods reveal evidence that humans and wildlife are exposed to more PFAS than previously estimated

(4) “To date, managing the risk of PFAS has focused primarily on
one chemical at a time,
or a small group of PFAS. This
approach has not been effective at controlling widespread
exposure to this large group of chemicals with known and
potential hazards… a class-based approach can be implemented
to more effectively eliminate non-essential uses of PFAS
develop safer alternatives, and clean up highly contaminated”

(5)” Because PFAA(includes PFOA and PFOS; see table below) can occupy sites on multiple receptors, proteins, and cell interfaces in the body, they can produce physiological effects across a range of tissues.”

(6)”Findings of suppressed vaccine response in humans and T cell-dependent antibody response in experimental animals led the US National
Toxicology Program (NTP) to classify PFOA and PFOS as
presumed immune hazards(immunosuppressants) to humans

(7) To date, a majority of human epidemiological studies have
focused on long-chain PFAA. In experimental animal models,
however, short-chain PFAA have shown effects similar to those
of long-chain PFAA

(8) “Some manufacturers have proposed that fluoropolymers
should not be grouped with other PFAS for regulatory
purposes, arguing that they are biologically inert because of
their high molecular weight. However, these chemicals can
release low-molecular weight PFAS and other hazardous
to the environment throughout their life cycle… fluoropolymer microplastics contribute to global plastic and microplastics debris, thus adding to ongoing environmental plastic and PFAS pollution.”

(9) “perfluoroalkanes and perfluoroalkylamines are generally inert, but
they can be very potent greenhouse gases, up to 3 orders of
magnitude more potent than CO2.”

“Unlike pesticides or pharmaceutical drugs, a significant portion of the more than 6,300 different types of PFAS on the market have little to no data on their use, toxicity and chemical structure and are not currently regulated or restricted in Canada, according to a report by the Canadian Environmental Law Association. In fact, those details are considered trade secrets.” —CBC’s Quirks and Quarks

From 2011 to 2017, maternal serum levels of the “forever synthetics” PFNA, PFDA and PFUdA in pregnant #Nunavut women increased by 19, 13 and 21% respectively. Overall they have 2X levels compared to other CDN women Here is a table that helps distinguish between some of the different #PFAS. Also see the 3- part Quirks and Quarks podcast dedicated to PFAS.

Types of PFAS ( for more physical data)