What is pfas
Last updated: April 1, 2026
Key Facts
- PFAS have been used since the 1940s in non-stick cookware, water-resistant textiles, food packaging, and aqueous film-forming foams (AFFF)
- "Forever chemicals" is an accurate description because PFAS do not break down naturally in the environment or human body over time
- PFOA and PFOS are the most widely studied PFAS chemicals, with PFOA formerly used in Teflon manufacturing
- Approximately 97% of the U.S. population has detectable PFAS in their blood serum according to CDC studies
- Health concerns include potential links to liver damage, thyroid disease, weakened immune response to vaccines, and reproductive issues
What Are PFAS?
Per- and polyfluoroalkyl substances (PFAS) are a group of human-made chemicals containing carbon-fluorine bonds that make them extremely stable and resistant to breaking down. These bonds are among the strongest in chemistry, giving PFAS their remarkable persistence. Scientists have identified thousands of different PFAS chemicals, though only a small fraction have been extensively studied. The most well-known include PFOA and PFOS, which dominated industrial use for decades.
Industrial and Consumer Applications
PFAS chemicals have been used since the 1940s in numerous products and applications:
- Non-stick and stain-resistant coatings on cookware, carpeting, and textiles
- Water and oil-repellent treatments on food packaging and paper products
- Aqueous film-forming foams (AFFF) used at airports, military bases, and fire training facilities
- Manufacturing processes for refrigerants, surfactants, and semiconductors
- Electronics manufacturing and hydraulic fluids in aircraft
Environmental and Health Persistence
PFAS earned the nickname "forever chemicals" because they do not break down through natural processes like sunlight, heat, or microbial degradation. Once released into the environment, PFAS persist indefinitely in soil, groundwater, and surface water. Bioaccumulation occurs when PFAS accumulate in living organisms and increase in concentration as they move up the food chain. This persistence means PFAS released decades ago remain present in environmental systems and human bodies today, with concentrations continuing to increase.
Exposure Routes and Detection
The general population is exposed to PFAS through multiple pathways: drinking water contamination, consumption of contaminated food (especially seafood, livestock, and processed foods), food contact materials, household dust, and indoor air. The CDC National Health and Nutrition Examination Survey found PFAS in the blood serum of approximately 97% of Americans, indicating widespread exposure. Occupational exposure affects workers in manufacturing, firefighting, and military settings at higher levels than the general population.
Health Effects and Regulatory Response
Research suggests PFAS exposure may be associated with increased cholesterol levels, liver damage, thyroid disease, decreased vaccine response, kidney and testicular cancer, and reproductive effects. The EPA established drinking water health advisories for PFOA and PFOS in 2022, and various states have set stricter drinking water standards. The FDA began regulating PFAS in food contact materials, though comprehensive regulations continue to evolve. Ongoing research aims to better understand the health impacts of chronic PFAS exposure across populations.
Related Questions
Where are PFAS most commonly found?
PFAS are found in drinking water, food (especially seafood and livestock), non-stick cookware, food packaging, carpeting, textiles, and aqueous film-forming foams at airports and military bases. They persist in landfills and contaminate groundwater through soil infiltration.
How can I reduce PFAS exposure?
Reduce exposure by using activated carbon filters on drinking water, avoiding non-stick cookware, selecting PFAS-free products, consuming less processed food and fast food, and choosing unwrapped fresh produce instead of packaged items whenever possible.
What are current PFAS regulations?
The EPA established health advisories for PFOA and PFOS in drinking water, and many states set stricter standards. The FDA regulates PFAS in food contact materials, while international regulations continue to develop as scientific evidence accumulates.
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Sources
- EPA - PFAS InformationPublic Domain
- Wikipedia - Persistent Organic PollutantsCC-BY-SA-4.0
- NIEHS - Perfluorinated ChemicalsPublic Domain