Frequently Asked Questions about PFAS
- What are PFAS?
These chemicals are an extensive family of more than 3,000 human-made substances that have commercially useful properties: they resist heat, oil, stains, grease, and water.
PFAS have been used since the 1950s in a wide range of products, including firefighting materials, non-stick cookware, stain resistant products for furniture and carpets, waterproofing for clothes and mattresses, food packaging, and personal care products. People regularly come into contact with these chemicals because of their everyday use.
Perfluorooctanesulfonic acid (PFOS) and (PFOA) were once the most commonly produced types of PFAS, and so scientists know the most about these two compounds. Because PFOS and PFOA don't break down in the environment and are a potential health concern, their production has been discontinued in the US. They have since been replaced by other PFAS compounds that don't accumulate to such high levels in wildlife and humans.
- What Should I know About PFAS and Health?
PFAS chemicals have a range of toxicities and are globally distributed. Studies in the U.S. and worldwide have found small amounts of PFAS in blood samples from the general human population and in wildlife. The Centers for Disease Control (CDC) is treating PFAS contamination as a public health concern.
Some animal studies show health effects from PFAS exposure, but human health studies are less conclusive. Some studies in humans have shown that PFAS at high levels may increase cholesterol levels; decrease how well the body responds to vaccines; increase the risk of thyroid disease; decrease fertility in women; increase the risk of serious conditions like high blood pressure and preeclampsia in pregnant women; and lower infant birth weights.
Studies do not clearly show whether PFAS cause cancer in people. Animal studies have shown PFOA and PFOS can cause cancer in the liver, testes, pancreas, and thyroid. However, the toxic effects of chemicals are not always the same across species, so the results of these studies may not accurately reflect effects of PFAS on humans. Further studies are needed to better understand the human health effects.
- What Should I Know About PFAS and Drinking Water?
- perfluorononanoic acid (PFNA)
- perfluorohexanesulfonic acid (PFHxS)
- perfluoroheptanoic acid (PFHpA)
- perfluorobutanesulfonic acid (PFBS)
- What Happens when PFAS get into the Environment?
- Because of their stable chemical structure, PFAS do not easily break down. They travel rapidly to groundwater where they can spread both vertically and laterally. PFAS tend to build up in the food chain and have been found throughout the Arctic, in both animals and plant life, and are suspected to have migrated there through the ocean and the air.
- How Do I Limit my Exposure?