What are Per- and Polyfluoroalkyl Substances (PFAS)?
Per- and polyfluoroalkyl substances (PFAS) are a group of human-made chemicals that were created for a variety of household and industrial uses. PFAS can repel oil, grease, and water, so they have been used in protective coatings for many different products including food packaging, nonstick cookware, carpets and upholstery (stain-protectants), mattresses and clothing (water-proofing), and have also been used in fire-fighting foams. Some of the more commonly known PFAS are perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). GenX chemicals are considered a replacement for PFOA and PFBS is considered a replacement for PFOS.
Who is exposed to PFAS?
Anyone can be exposed to PFAS. Ingestion is the primary route of exposure to PFAS for the general public. This can be due to food that has been stored or cooked in materials containing PFAS, by eating contaminated fish and shellfish, or by drinking contaminated water. People who live near PFAS production facilities or places where PFAS-containing firefighting foams were used are at higher risk of exposure from groundwater contamination.
How can PFAS affect my health?
Health effects from exposure to low levels of PFAS are not well known, but may include elevated cholesterol levels, interference with thyroid function, preeclampsia, and decreased fertility. PFAS may also affect the immune system and a developing fetus or child. Animals exposed to high doses of some PFAS have shown changes in the liver, thyroid, and pancreatic function, as well as some changes in hormone levels.
How likely are PFAS to cause cancer?
Some studies have found increases in prostate, kidney, and testicular cancers in workers exposed to PFAS and people living near a PFAS production facility. Findings from other cancer studies report otherwise or are inconsistent.
How can PFAS affect children?
PFAS may affect growth, learning, and behavior in infants and older children.
Is there a medical test to show whether I have been exposed to PFAS?
PFAS can be measured in blood, but this test is not commonly performed in doctor’s offices, and the results of such tests would not predict health outcomes.
How can I reduce my exposure to PFAS?
Filters containing activated carbon or reverse osmosis membranes have been shown to effectively remove PFAS from drinking water. You can further reduce your exposure by avoiding products that contain PFAS or eating food that was packaged in materials that contain PFAS. PFAS can be found in some stain-resistant coatings on carpets and upholstery, water-resistant clothing, personal care products, and cosmetics. Previously PFAS were included in grease-resistant food wrappers or boxes and microwave popcorn bags, but the FDA announced in February 2024 that the food industry had completed a voluntary phase-out of use of PFAS in food-contact packaging sold in the US.
Has the federal government made recommendations to protect human health?
In 2024, EPA set primary drinking water standards for six PFAS (PFOA, PFOS, PFNA, PFHxS, PFBS, and GenX chemicals) that set maximum contaminant levels (MCLs) for these chemicals in drinking water. Drinking water systems will be required to test for these chemicals, report results to consumers, and reduce concentrations in treated water if they were found to exceed the standard. EPA also set maximum contaminant level goals (MCLGs), which are target concentrations that public water supplies should reach if possible, but EPA does not require water systems to reach these concentrations. Values are in the table below.
| Chemical | Final MCLG (ppt) | Final MCL (ppt) |
| Perfluorooctane sulfonic acid (PFOS) | Zero | 4.0 |
| Perfluorooctanoic acid (PFOA) | Zero | 4.0 ppt |
| Perfluorohexane sulfonic acid (PFHxS) | 10 ppt | 10 ppt |
| Perfluorononanoic acid (PFNA) | 10 ppt | 10 ppt |
| Hexafluoropropylene oxide dimer acid (HFPO-DA) | 10 ppt | 10 ppt |
| Mixtures containing two or more of PFHxS, PFNA, HFPO-DA, and Perfluorobutane sulfonic acid (PFBS) | Hazard Index | Hazard Index |
*Maximum Contaminant Level Goal (MCLG): The level of a contaminant in drinking water below which there is no known or expected risk to health and allows for an adequate margin of safety. MCLGs are non-enforceable public health goals. Maximum Contaminant Level (MCL): The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology and taking cost into consideration. MCLs are enforceable standards. ppt: parts per trillion. Hazard Index (HI): The Hazard Index is used to health risk from chemical mixture. The HI is made up of a sum of fractions. Each fraction compares the level of each PFAS measured in the water to the highest level determined not to have risk of health effects.
What if I have a private well?
The quality and safety of drinking water from private domestic wells are not regulated by the federal government under the Safe Drinking Water Act nor by most state governments and laws. You can get your water tested for PFAS to confirm levels are low. You can get more information about testing your well at the Private Well Program page.
Where can I get more information?
PFAS are a topic of current research by public health agencies. You can get more information at the following pages:
- VDH Guidance on PFAS and Private Wells
- ATSDR’s Per- and Polyfluoroalkyl Substances (PFAS) and Your Health
- EPA’s Per- and Polyfluoroalkyl Substances (PFAS)
- NIOSH Workplace Safety and Health Topics: Per- and polyfluoroalkyl substances (PFAS)
Updated 2024