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Emerging Contaminants - PFOS and PFOA

The United States Environmental Protection Agency (US EPA) has identified two chemicals, known as PFOS (perfluorooctane sulfonate) and PFOA (perfluorooctanoic acid) as emerging contaminants. These chemicals are part of a class of chemicals known as per- and polyfluoroalkyl substances (PFAs), which are currently unregulated by the federal government. PFAs have been used in a number of industrial and commercial products such firefighting foam, as well as coatings that repel water, oil, stains and grease. Thus, people may be exposed to PFOS and PFOA through air, water, or soil from industrial sources and from consumer products.

In 2013, major water supply companies began testing their wells for PFOS and PFOA. In May, 2016, the US EPA established a health advisory level for PFOS and PFOA in drinking water. Health advisories are non-enforceable, non-regulatory levels in drinking water that are developed by the US EPA to provide information on contaminants that may be found in drinking water. The health advisories are established after careful review of the research and science that is available on a specific contaminant. They provide information on potential health risks from exposure to a chemical. In addition, the health advisories provide information on appropriate actions that can be taken when chemicals are detected in drinking water.

The drinking water health advisory level for PFOS and PFOA is 0.07 parts per billion (ppb), which is the same as 70 parts per trillion (ppt). When both PFOA and PFOS are detected in a water supply, the combined concentration should be compared to the 0.07 ppb health advisory. This health advisory has been established to provide everyone, including the most sensitive populations (developing fetus and infants who may be breastfed or fed formula mixed with water), with a margin of protection from exposure to PFOS and PFOA in drinking water, even if that exposure were to occur throughout their life. Health-protective assumptions are incorporated in the determination of the health advisory to provide this margin of protection and account for uncertainty in the assessment.

In the absence of federal regulation, New York State took aggressive action ‎and in June, 2016 became the first state in the nation to regulate PFOS and PFOA as hazardous substances, which enables the State to use the legal authority and financial resources of the State Superfund Program to clean up contaminated sites. For more information about the regulation of PFOA and PFOS in New York State, click here.

For Information regarding:


Suffolk County Water Authority 2016 Drinking Water Quality Report:

Suffolk County Government

H. Lee Dennison Bldg

100 Veterans Memorial Hwy
P.O. Box 6100
Hauppauge, NY 11788

Riverhead County Center

County Road 51
Riverhead, NY 11901