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Per- and poly-fluoroalkyl substances – history and proliferation

  • Laura Alcock
  • Jul 28
  • 2 min read

80 years since Teflon® was trademarked for PTFE, per- and poly-fluoroalkyl substances (PFAS) thousands of different chemicals now exist within this class of “forever chemicals” which are used for industrial, as well as consumer applications. This series will review environmental and human health impacts of PFAS. This article examines how PFAS were developed and how they grew.


What’s in this beaker?

In 1934, Fritz Schoffler and Otto Scherer accidentally invented polychlorotrifluoroethylene (PCTFE), discovering that the reactants they had left in a vessel overnight had resulted in a product. After cleaning the vessel, it was still significantly heavier than the day before and no solvent, acid nor alkali could remove it. Eventually, the team decided to cut the vessel open and found that the residue was rigid and maintained its shape without the supporting vessel, in fact, it was nigh indestructible with remarkable abrasion and heat resistance to complement its chemical invulnerability. However, there was little pursuit of PCTFE for some years.


Four years later, whilst investigating the reaction properties of tetrafluoroethylene, Roy Plunkett and Jack Rebok compressed and froze a sample of the chemical. They discovered that this has resulted in the formation of a “white, waxy solid” which, like its predecessor was virtually indestructible with incredible thermal and chemical stability, as well as durability. This was polytetrafluoroethylene (PTFE).


What do we do with PTFE?

Though they were heavily involved in the development work of the Manhattan project, upscaling production would be fraught with dangers and difficulties for the Du Pont team. In fact, three scientists involved in the development of a larger-scale PTFE production process would die in 1944 after exposure to PFAS-containing chemicals and, later, two more would die in an explosion at the laboratory.


Meanwhile, Joseph Simons successfully developed and patented a safer method for commercial-scale production of fluorochemicals and PFAS. In 1945, Du Pont trademarked the product name Teflon and 3M manufacturing acquired a license from Joseph Simons to use the Simons process for manufacture.


The 1950’s heralded the start of commercial PFAS production, with M. W. Kellog commercialising PCTFE as Kel-F and Du Pont launching commercial production and sales of Teflon. 1953 saw Patsy Sherman and Samuel Smith of 3M discover perfluorooctane sulfonic acid (PFOS).


However, it would be Marc Gregoire’s wife chastising his efforts to coat fishing lines with Teflon and telling him to “do something useful with it” that would open the flood gates for what would become overuse of PFAS. In 1954, he launched Tefal who applied a Teflon coating to the interior surface of cookware.


Creating a monster

Efforts to create PFAS materials resulted in proliferation of the variation of chemicals produced with companies all over the world looking to develop a material with the properties of PTFE, but not using a patented process. As a result, in 2018, almost 4,7002 different PFAS chemicals were known to exist and be used, even in cosmetics.


References

1. Zhou, T., et al., Journal of Hazardous Materials, 2024, 466, 133637. https://doi.org/10.1016/j.jhazmat.2024.133637

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