DOH News Release: Low levels of PFAS detected in Waipahu Wells II

Posted on Jan 6, 2023 in Latest Department News, Newsroom

HONOLULU – Low levels of perfluorohexanoic acid (PFHxA) were recently detected in water samples collected at the Waipahu Wells II Granular Activated Carbon (GAC) Treatment Facility, which is part of the Waipahu-Ewa-Wai‛anae water system. PFHxA is part of the group of perfluoroalkyl and polyfluoroalkyl substances (PFAS).

PFAS are chemicals that are common drinking water and environmental contaminants. While there is no EPA health advisory for PFHxA, there is a Hawai‛i Department of Health (DOH) PFHxA environmental action level of 1.0 micrograms per liter (ug/L).  Levels detected in Waipahu Wells II GAC ranged from 0.0020 ug/L to 0.0023 ug/L.

According to State Toxicologist Dr. Diana Felton, “The levels found at these wells are significantly below the action level and based on current information, are not expected to pose a risk to human health. It is important to note that research regarding the health impacts of PFHxA and other PFAS is ongoing and our understanding of the health impacts of these chemicals is evolving.

“As we learn more about PFAS and possible risk to health, it remains a priority to ensure that

the public is aware of these contaminants in drinking water. While these detections do not pose an acute risk to public health, we continue to work with EPA and other stakeholders to reduce PFAS exposures and establish enforceable PFAS limits that protect public health.”

While no action is necessary for users at this time, those concerned may use a home filtration option to reduce PFAS. Click here for an EPA article describing technologies for reducing PFAS in drinking water. Filters should be NSF certified for removing PFAS. A list of NSF certified filters can be found here.

According to the EPA, PFAS are fluorinated organic chemicals that have been used extensively in consumer products such as carpets, clothing, fabrics for furniture, paper packaging for food, and other materials (e.g., cookware) designed to be waterproof, stain-resistant, or non-stick.  They are also a component of fire-fighting foam and have many industrial uses. For general information on PFAS, please see

The Waipahu-Ewa-Wai‛anae water system serves approximately 217,500 individuals and is located on the leeward side of O‛ahu. The system continues to be in full compliance with all federal and state standards for drinking water.

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Media Contact:

Brooks Baehr

Communications Office

Email: [email protected]

Phone: (808) 586-4417