About 650 Hawaiian residents have relied on bottled water since March, after the state health department detected synthetic chemicals, known as PFASs, in the local water system.

The contamination dates back to at least October, when the Hawaii Department of Health detected the chemicals in one of two wells serving Kunia Village, an affordable housing complex. on O’ahu.

The Department announced in january that the levels detected exceeded those of the Environmental Protection Agency proposed limit for two types of PFAS, called PFOA and PFOS, in drinking water, as well as the Hawaii state limit, above which communities are expected to treat their water systems or provide an alternative source. However, the concentration is below the current EPA limit.

Kunia Village stopped using the contaminated well after that. Then, in early March, the operator of the water system began dispensing bottled water to residents out of fear that the second well could also be contaminated, which the health department confirmed tests last week.

Residents were instructed to use bottled water for drinking or brushing teeth and tap water for washing hands, laundry or bathing.

“We just feel it’s important to move quickly and conservatively,” said Stephanie Whalen, president of the Kunia Water Association.

PFAS stands for perfluoroalkyl and polyfluoroalkyl substances, but they are more often referred to as “permanent chemicals” because they are nearly impossible to destroy, so they can remain permanently in the air, water, and soil.

The class of chemicals is associated with health consequences, including low birth weight, high cholesterol and thyroid disease. PFOA, in particular, has been linked to a increased risk of kidney cancer. TO study published last year found that exposure to high levels of PFOS was associated with increased risk of liver cancer.

PFAS are used in the manufacture of consumer products such as food packaging, cosmetics, and textiles due to their ability to resist stains, grease, and water. They are also found at some military sites due to the use of a PFAS-based firefighting foam that dates back to the 1970s. The foam is still used by the military to respond to emergencies but has stopped using it for testing and training.

PFAS contamination is common

PFAS contamination in water is widespread in the US. The Environmental Working Group, a research and advocacy organization focused on toxic chemicals, told NBC News that at least 1500 sites would violate EPA’s proposed PFAS limits for drinking water (4 parts per billion) that the agency expects to finalize At the end of this year.

Meanwhile, the EPA said in march that up to 6,300 water systems, serving up to 94 million people, contain PFAS levels above proposed limits.

“There are very few places that we’ve looked for PFAS and haven’t found them,” said Jamie DeWitt, a professor of toxicology at East Carolina University who reviewed the results from the Kunia Village water samples. «That’s just a testament to how ubiquitous they are in the environment.»

But Kunia levels are higher than the average background concentrations found across the country, according to Anna Reade, a senior scientist with the Natural Resources Defense Council, an environmental advocacy group.

“This is a pretty alarming level that they’re picking up on,” Reade said.

In a Kunia Village well, PFOA levels were up to twice the EPA’s proposed limit, and PFOS levels were up to 3.5 times higher. In the other, PFOA levels were between five and seven times higher than the proposed threshold, and PFOS levels were at least 11 times higher.

“It hits all the marks of being too contaminated for people to drink safely,” Reade said.

More water systems are beginning to test PFAS

Hawaii’s health department said it has been testing small water systems located near potential PFAS hot spots, such as industrial or military sites, with the help of an EPA grant.

Kunia Village is one such site, the department said, but added that it did not know how long PFAS was present in the area’s water before testing in October.

Kunia village in 2017.Kristen Wong / US Army

“The main concern is that people may have been consuming this for many, many years, maybe even decades,” DeWitt said.

However, PFAS testing is becoming more common: The Safe Drinking Water Act requires large public water systems, and some small and medium-sized ones, to test for chemicals through 2025 and report results through the following year.

The type of monitoring Hawaii is doing is voluntary, Reade said, but in the next few years, «we’re going to get a lot more information about what we’re dealing with in our drinking water.»

Individual water systems respond to high levels of PFAS in different ways. Some provide temporary bottled water, but Reade said many also employ long-term solutions like connecting to a new water source or installing a specialized treatment system.

However, it may take a while for communities to decide or implement such solutions. The city of Emmaus, Pennsylvania, for example, is still weighing its options more than a year after elevated levels of PFAS were detected in their water.

Hawaii’s PFAS problem may stem from military activity

The source of the contamination at Kunia Village has not been identified, but the health department said the PFAS compounds detected appear to match those at other sites with known fire-fighting foam contamination.

DeWitt also said that in the Kunia Village case, «it appears that the sources are military sources, rather than an industrial source or landfill.»

The health department said it is waiting for more information from the Army, which owns one of the wells.

The US Army Garrison in Hawaii said it does not know the source of the contamination, but is investigating whether PFAS-containing materials may have been stored, used or released at nearby military sites.

In April, Whalen said, Kunia Village began running water from a different source through the water line to remove contamination. He is waiting for the most recent test results.

«Those results are clean, great. We’ll stop drinking bottled water. If they don’t, we’ll stick with bottled water,» Whalen said.

Low levels of PFAS have been detected detected in various water systems in Honolulu this year as well. Reade said that’s not surprising given the state’s history of military activity.

«I think unfortunately it’s going to be a problem that Hawaii has to deal with beyond just a few wells,» he said.