General PFAS Information
PFAS Overview
PFAS (Per- and PolyFluoroAlkyl Substances) are a group of synthetic chemicals commonly referred to as “forever chemicals” due to their extreme persistence in the environment and resistance to degradation. The name PFAS encompasses a wide range of compounds with similar chemical structures and names such as PFAA, PFSA, and PFCA.
History of PFAS
The discovery of PFAS dates back to 1938, when scientists at the American chemical company DuPont accidentally created PolyTetraFluoroEthylene (PTFE) while researching refrigerants. PTFE was later commercialized under the brand name Teflon and initially used for military applications during World War II, including as a coating for equipment involved in the Manhattan Project.
1938 discovery of Teflon. Left to right: Jack Rebok, Robert McHarness, and Roy Plunkett Photo courtesy of Hagley Museum and Library
After World War II, additional applications for Teflon were discovered, leading to its widespread adoption in both consumer goods and industrial settings. Its unique properties, such as non-stick, heat-resistant, and chemical-resistant capabilities, made it useful for products like cookware, textiles, electronics, and machinery components. PFAS has been used in everyday items like fabrics, food packaging, and cosmetics. These products can release PFAS during manufacturing, use, or disposal.
Environmental Release of PFAS
The environmental persistence and toxicity levels of PFAS was not well understood for decades despite widespread use. Factories discharged wastewater and air emissions containing PFAS, fire suppression foam such as AFFF (Aqueous Film-Forming Foam) used by the military and airports led to contamination of soil and groundwater, and consumer products containing PFAS often end up in landfills where they leach into the soil and groundwater.
PFAS Chemical Properties
The PFAS molecules consists of carbon atoms bonded to fluorine atoms, forming carbon-fluorine (C-F) bonds, one of the strongest bonds in chemistry. This bond is exceptionally stable, making PFAS highly resistant to heat, chemical reactions, and biological degradation. Many PFAS compounds also have a hydrophobic (water-repelling) and lipophobic (oil-repelling) chemical characteristics. This dual nature allows PFAS to form protective barriers against moisture, grease, and stains, explaining their widespread use in consumer and industrial products. However, this same stability and resistance to breakdown are what make PFAS persistent in the environment, contributing to their accumulation in water, soil, and living organisms over time.
Example of a PFAS chemical containing the Carbon (C) – Fluorine (F) bonds