Polyfluoroalkyl substances, or PFAS, have been detected in the Waipahu-Ewa-Waianae water system on Oahu, although they are “significantly below” levels that would pose a risk to human health, the state Department of Health has reported.

The DOH in a news release today said that low levels of perfluorohexanoic acid, or PFHxA, were detected in water samples at the Waipahu Wells II Granular Activated Carbon Treatment Facility, which is part of the leeward area water system.

The levels detected within the wells ranged from 0.002-0.0023 micrograms per liter, the health department reported. The environmental action level set by the DOH is 1 microgram per liter.

No action is necessary for the 217,500 users of the water system, the DOH said.

Those concerned can use a home filtration system to reduce PFAS, which are common drinking water and environmental contaminants, the DOH said.

According to the EPA, PFAS have been used extensively in consumer products such as carpets, clothing, fabrics for furniture, paper packaging for food and other materials designed to be waterproof, stain-resistant or non-stick.

They were also found in 1,300 gallons of firefighting foam that was leaked from the Navy’s Red Hill fuel facility in November.