What Are PFAS?

PFAS (per- and polyfluoroalkyl substances) are a class of chemicals that companies add to a wide variety of consumer products to make them non-stick, waterproof, and stain-resistant. There are currently more than 4,700 different PFAS chemicals on the market, making them among the most ubiquitous synthetic chemicals in the world.

PFAS can be found in products such as stain-resistant carpets and upholstery, waterproof apparel, floor waxes, non-stick cookware, greaseproof food packaging, dental floss, and some cosmetics. They are also used in firefighting foams for putting out fuel fires. People can be exposed to these chemicals from direct contact with products, or through the air they breathe or the food they eat. They can also be exposed through drinking water.
In fact, millions of Americans today are exposed to drinking water contaminated with PFAS as a result of the chemicals being released into the environment from fire training areas, industrial sites, and waste disposal. A 2016 study reported that more than 16 million Americans are exposed to these contaminants in drinking water; a more recent estimate put that number at 110 million. This map shows you where contamination sites are located in the United States.
While their strong chemical bonds make them very effective at repelling water and oil even at high temperatures, these same characteristics also make PFAS extremely persistent, meaning they don’t break down in the environment. Scientists and health professionals are concerned about the public’s exposure to PFAS because the chemicals have been linked with many health problems, including thyroid disease, cancer, high cholesterol, obesity, effects on the immune system, increased susceptibility to breast cancer, and others.
Approximately 98 percent of Americans have PFAS in their bodies, and the chemicals remain in the body for years.
That’s why the scientific research community is working hard to better understand these contaminants —how people are exposed and how they impact human health — in order to find solutions to protect the public, especially vulnerable populations, from these hazardous chemicals.
See the Resources section to learn more about PFAS.