Home Health and Exposure
People and PFAS
Health and Exposure
Nearly everyone in the U.S. has some PFAS in their blood. Here is how exposure happens, what studies have linked to certain PFAS, what blood tests can and cannot tell you, and practical steps to reduce exposure.
How people are exposed
EPA says people can be exposed to PFAS by: [1]
- working in occupations such as firefighting or chemicals manufacturing and processing;
- drinking water contaminated with PFAS;
- eating certain foods that may contain PFAS, including fish;
- swallowing contaminated soil or dust;
- breathing air containing PFAS;
- using products made with PFAS or packaged in materials containing PFAS.
ATSDR adds that exposure can come from accidentally swallowing residue or dust from products such as stain-resistant carpeting or water-repellent clothing, and that “for most PFAS, showering and bathing in water containing PFAS should not significantly increase exposure.” [2] [3]
PFAS in people’s blood
Since 1999 the National Health and Nutrition Examination Survey (NHANES), run by the Centers for Disease Control and Prevention, has measured PFAS in the blood of the U.S. population. ATSDR states that “nearly all people in the U.S. have PFAS in their blood.” [4]
Levels of the two most studied PFAS have fallen as their production ended. Between 1999-2000 and 2018-2019, blood PFOS levels declined by more than 85% and blood PFOA levels by more than 70%. [4] ATSDR also notes that “people may be exposed to other PFAS as PFOS and PFOA are phased out and replaced.” [4]
What studies have found
ATSDR summarises the evidence this way: “Epidemiological evidence suggests associations between increases in exposure to (specific) PFAS and certain health effects.” Those effects are: [5]
- increases in cholesterol levels (PFOA, PFOS, PFNA, PFDA);
- lower antibody response to some vaccines (PFOA, PFOS, PFHxS, PFDA);
- changes in liver enzymes (PFOA, PFOS, PFHxS);
- pregnancy-induced hypertension and preeclampsia (PFOA, PFOS);
- small decreases in birth weight (PFOA, PFOS);
- kidney and testicular cancer (PFOA).
Associations, not proof of cause. These findings link higher exposure to specific PFAS with these outcomes in groups of people. ATSDR adds that “scientists are still learning about the health effects of exposures to mixtures of different PFAS” and that “additional research may change our understanding.” [5]
Cancer classification
On 1 December 2023 the International Agency for Research on Cancer (IARC), part of the World Health Organization, classified PFOA as carcinogenic to humans (Group 1), “on the basis of sufficient evidence for cancer in experimental animals and strong mechanistic evidence” in exposed humans. It classified PFOS as possibly carcinogenic to humans (Group 2B). [6]
PFAS blood tests
In 2022 the National Academies of Sciences, Engineering, and Medicine recommended that clinicians “offer PFAS blood testing to patients who are likely to have a history of elevated exposure.” [7] Their guidance uses the combined level of several PFAS in blood:
| Combined PFAS blood level | National Academies interpretation |
|---|---|
| Below 2 ng/mL | Not expected to have adverse health effects |
| 2 to 20 ng/mL | Potential for adverse effects, especially in sensitive populations |
| Above 20 ng/mL | May face a higher risk of adverse effects |
For people in the middle and higher groups, ATSDR’s summary of that guidance encourages exposure reduction and screening for dyslipidemia (abnormal blood fats), hypertension in pregnancy and breast cancer. [8]
A blood test has limits. ATSDR states that “PFAS blood levels do not predict future health outcomes,” and that a result cannot pinpoint a health problem or guide treatment. [9] Talk to a clinician about whether testing makes sense for you.
Higher exposure at work
CDC’s National Institute for Occupational Safety and Health (NIOSH) lists chemical manufacturing workers, firefighters and ski wax technicians among occupations “known to be exposed more than the general U.S. population.” [10] Handling PFAS materials and breathing the dust, aerosols or fumes can lead to exposure by inhalation. [11]
Reducing your exposure
EPA suggests these steps: [12]
- Find out whether PFAS are in your drinking water.
- Consider an in-home water filter certified to lower PFAS levels (see treatment and filters).
- If you have a private well, test it regularly and compare the results with your state’s standards.
- Avoid eating fish from waterways affected by PFAS, and follow state or tribal fish advisories.
On breastfeeding, ATSDR notes that “due to the many benefits of breastfeeding, the Centers for Disease Control and Prevention (CDC) and American Academy of Pediatrics recommend that most nursing people continue to breastfeed.” [13]
This page summarises public health sources for general information. It is not medical advice. If you are concerned about PFAS exposure, speak with a healthcare provider.
Sources
- U.S. EPA, Our Current Understanding of the Human Health and Environmental Risks of PFAS, updated 14 July 2026.
- ATSDR, Preventing PFAS Exposure, 12 November 2024.
- ATSDR, PFAS and Your Health, reviewed 22 July 2025.
- ATSDR, Fast Facts: PFAS in the U.S. Population, 12 November 2024.
- ATSDR, How PFAS Impacts Your Health, reviewed 22 July 2025.
- IARC, IARC Monographs evaluate the carcinogenicity of PFOA and PFOS, 1 December 2023.
- National Academies of Sciences, Engineering, and Medicine, New Report Calls for Expanded PFAS Testing for People With History of Elevated Exposure, 28 July 2022.
- ATSDR, Clinical Evaluation and Management: PFAS Information for Clinicians.
- ATSDR, Testing for PFAS, 12 November 2024.
- CDC NIOSH, PFAS and Worker Health, 25 September 2024.
- ATSDR, Human Exposure: PFAS Information for Clinicians.
- U.S. EPA, Meaningful and Achievable Steps You Can Take to Reduce Your Risk, updated 14 July 2026.
- ATSDR, Reducing Risk, 12 November 2024.
Last reviewed: 29 September 2026.