Perfluorooctanesulfonic acid
Part of a class of synthetic compounds known as per- and polyfluoroalkyl substances (PFAS) widely used to make products more resistant to stains, water, and grease. It is found in fabrics, fire-fighting foams, cleaning products, hydraulic fluids, metal plating, and paper. Although PFOS production has been phased out in the US, exposure is still a major concern due to its high degree of persistence in the environment and in the body as well as the use of legacy products and imported goods. Many adverse health effects have been linked to PFOS exposure, including developmental, liver, and immunological problems and increased cancer risk. EPA has found that there is suggestive evidence that PFOS is a human carcinogen.
Health Guideline Level (HGL)
0 ppb
Maximum level that poses minimal health risk based on the latest science
Health Effects
As with many PFAS compounds, research into the health effects of PFOS is rapidly evolving. Epidemiological studies have shown associations between elevated PFOS levels and increased total and low-density lipoprotein cholesterol ('bad cholesterol') as well as immune toxicity (decreased antibody response). Animal studies indicate that PFOS exposure is related to adverse developmental effects, liver toxicity, immune toxicity, and an increased risk of liver and pancreatic cancer.
Affected Organs & Systems:
Common Sources
- Not naturally occurring, so its widespread detection in drinking water can be attributed to human release
- Includes industrial waste, the leaching of contaminated sites, stormwater runoff, the chemical breakdown of other PFAS, and wastewater discharge
- The presence of PFOS in drinking water is strongly correlated with the presence of major industrial sites in the area
How to Remove It
Water filters certified under the following NSF standards are effective at removing Perfluorooctanesulfonic acid:
Health Guideline Level
The HGL represents the maximum level that poses minimal health risk based on the latest scientific research. It's often more protective than federal legal limits.
Contaminant Type
Perfluorooctanesulfonic acid is classified as a PFAS contaminant.
This contaminant primarily affects the thyroid, developmental, and other systems.
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Find out if Perfluorooctanesulfonic acid is in your tap water.
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