East Hampton Area PFAS in Drinking Water
Updated July 22, 2026
The New York State Department of Health is assisting with the East Hampton investigation of per- and polyfluoroalkyl substances (PFAS) groundwater contamination that is being led by New York State Department of Environmental Conservation and the Suffolk County Department of Health Services. The investigation will evaluate potential sources of per- and polyfluoroalkyl substances (PFAS), and in particular a less common form of PFAS, perfluoropropanoic acid (PFPrA), and potential impact on drinking water in the area.
Current Situation
Perfluoropropanoic acid (PFPrA) was the primary PFAS detected in public drinking water supply wells and groundwater in East Hampton. As a result, Suffolk County Department of Health Services is offering testing for people on private wells in affected areas.
There is no enforceable contaminant-specific drinking water standard for PFPrA. New York State Department of Health has developed a preliminary PFPrA screening level of 3 parts per billion (ppb) in drinking water. New York State and Suffolk County authorities will use this screening level for assessing health risks and actions to address PFPrA in private and public well water during the East Hampton investigation. More information about this screening level is found in the New York State Department of Health Decision Support Document: Recommended Preliminary Site-Specific Screening Value for Perfluoropropanoic acid (PFPrA).
Frequently Asked Questions
Why is the New York State Department of Health recommending a site-specific screening level of 3 parts per billion for PFPrA in the East Hampton community?
- Suffolk County Department of Health Services is testing private wells in East Hampton as part of a larger investigation of contaminated groundwater that contains PFPrA in the East Hampton community. There are no Federal or State drinking water standards for PFPrA.
- DOH has reviewed toxicology information and evaluations conducted by Federal agencies on PFPrA. It is using the Health-Based Screening Level of 3 parts per billion (ppb) developed by the United States Geological Survey in 2023 for this investigation. This value is supported by the available science and is highly protective of public health. New York State recommends using this value for evaluating PFPrA test results from private wells in East Hampton. This value can also be used by the Suffolk County Water Authority in evaluating the results of public supply well testing for PFPrA.
- This 3 parts per billion screening level for PFPrA is NOT an enforceable drinking water standard, also known as maximum contaminant level. It is recommended for use in evaluating drinking water sample results where PFPrA is detected.
What are health effects of PFPrA?
- PFPrA is not widely studied in the scientific literature. The only study is of rats that were exposed to high levels, much higher than those found in drinking water. Results showed liver effects, which is a common health effect with other similar PFAS.
- PFPrA is considered less toxic than more commonly detected and researched PFAS in drinking water, such as PFOA or PFOS. The body can get rid of PFPrA relatively quickly so it is unlikely to build up to harmful levels. Even levels at or slightly above 3 parts per billion are still well below health effect levels seen in animal testing.
- PFPrA is similar to another PFAS, perfluorobutanoic acid (PFBA) that has been more extensively studied. PFBA also has effects on the liver. Several states and the Federal government have developed drinking water screening levels for PFBA ranging from 1.8 to 24 parts per billion. These similarities provide more support that the 3 parts per billion PFPrA screening level is set appropriately for public health protection.
- DOH considers 3 parts per billion PFPrA a site-specific screening level because we have limited information about it in the scientific literature, and it is an uncommon form of PFAS in New York State. We will continue to evaluate new information as it becomes available and adjust the screening level for PFPrA as needed.
Is PFPrA considered a “forever chemical” like other PFAS?
- In terms of the environment, it is a forever chemical because, like other PFAS, it remains in the environment for a long time. But unlike other forever chemicals, PFPrA does not appear to remain in the human body for a long time or build up in in the body over time.
Has anyone in Suffolk County ingested water containing PFPrA above 3 parts per billion?
- Specific information on the levels or the amount of time that people may have been exposed to PFPrA in drinking water are difficult to answer. Fortunately, Suffolk County Water Authority (SCWA) took swift and appropriate actions to minimize use of the affected wellfield for drinking water after PFPrA was detected.
- Based on the scientific literature of similar PFAS compounds, PFPrA is unlikely to build up in the human body from ongoing exposures. The concern for short-term exposure is decreased because PFPrA is rapidly cleared from the body and the screening level is based upon the prevention of chronic effects from daily long-term exposure.
New York State has a drinking water standard for Unspecified Organic Contaminants (UOCs) of 50 parts per billion. Why is it using a lower level for PFPrA?
- Many PFAS, including PFPrA, are considered unspecified organic contaminants and are subject to a drinking water standard of 50 parts per billion. However, in this case we had enough chemical-specific information to support a more health-protective screening level. Our evaluation found that 3 parts per billion of PFPrA is scientifically supportable, chemical-specific, and more health-protective for responding to PFPrA detections during the East Hampton PFAS investigation.
- The evidence for this determination is available in a Decision Support Document developed by the Department. It serves as the State Health Department’s recommendation to aid in health-based decision-making for specific investigations. However, this screening level is not an enforceable drinking water standard.
