The Hawaii Department of Health reports that perfluoroalkyl and polyfluoroalkyl substances, or PFAS, have for the first time been detected in water samples collected from a water system in Waialua.

The Waialua Sugar Pump 2 water system, where PFAS were detected, serves about 500 people in the northwest part of Oahu, according to health officials in a news release today. It is a private system owned by OPU Waialua Corp.”

DOH said it was notified of the initial detection of the substances confirmed by lab reports in an email on Nov. 16. The lab reports were dated Aug. 30 and Nov. 13.

The detected PFAS levels are below the U.S. Environmental Protection Agency’s proposed maximum contaminant levels of 4.0 nanograms per liter — the highest level allowed in drinking water — for Perfluorooctanoic acid (PFOA) and Perfluorooctanesulfonic acid (PFOS).

The calculated “hazard index,” at 0.015, is also below the EPA’s proposed compliance threshold of 1.0, DOH said.

According to the EPA, PFAS are manufactured chemicals that have been used extensively in consumer products since the 1940s.

They have been used in carpets, clothing, fabrics for furniture, paper packaging for food and other materials designed to be waterproof, stain-resistant or non-stick. They are also a component of firefighting foam.

Studies have shown exposure to certain levels of PFAS may lead to increased risk of some cancers, some immune and developmental effects, as well as decreased fertility.

DOH shared the following table of PFAS levels detected at the Waialua Sugar Pump 2 water system:

>> PFOA, 2.1-2.4 nanograms per liter (parts per trillion)

>> PFOS, 3.1-3.7 ng per liter

>> PFBS, 2.6-2.9 ng per liter

>> PFPea, 2.5-2.7 ng per liter