There is no certainty the water supplies are free of toxic PFAS given laboratories can't entirely rule out their presence.
In Penobscot County, 11 of 12 water districts that manage their own sources of water have gotten back their PFAS test results. Of those 11 water districts, eight had non-detect levels of PFAS, according to results collected by the state and the Bangor Daily News. The three districts with PFAS are Newport, Dexter and Patten. Credit: Erin Rhoda / BDN

Most water districts in Penobscot County are not finding “forever chemicals” in their drinking water supplies, but given laboratories can’t entirely rule out their presence, there’s no guarantee the water supplies are free of the toxic chemicals.

Water districts across the state are required to test their drinking water for per- and polyfluoroalkyl substances, also known as PFAS, by the end of the year. In Penobscot County, the 12 water districts that manage their own sources of water have gotten back their results. Nine of them had non-detect levels of PFAS in their drinking water, according to results collected by the state and the Bangor Daily News.

That means it’s possible there are truly no PFAS in the Bangor, Brewer, Corinna, Exeter, Lincoln, Millinocket, East Millinocket, Old Town and Orono-Veazie water districts. Or it’s possible there are trace amounts, but the testing technology is not reliable enough to confirm them.

Three water districts have PFAS: Those based in Newport, Dexter and Patten. Their levels do not exceed the threshold at which they would be required to filter out the chemicals, but they do exceed the recommended level set by the federal government.

Two additional towns purchase their water from nearby municipalities: Hampden gets its water from Bangor, and Howland gets it from Lincoln.

PFAS are a group of thousands of synthetic chemicals linked to many serious illnesses. They are present in a range of household and industrial products to make them resistant to heat, oil, stains, grease and water, and they have contaminated soil, water and food in Maine and beyond.

“It’s good news, because it’s fairly low even in the ones where there has been some detection. But obviously none is better than some, and that’s clear from the [Environmental Protection Agency’s] health advisory numbers,” said Jean MacRae, an associate professor of civil and environmental engineering at the University of Maine.

The biggest water districts in the county did not detect PFAS. Bangor owns or protects 98 percent of the forested watershed surrounding its source of water, Floods Pond in Otis, said Kathy Moriarty, general manager of the Bangor Water District.

“We have a pretty unique, pristine situation with our watershed,” she said. “We are fortunate to have such a protected source of supply.”

The three water districts with PFAS discovered a specific compound, perfluorooctanoic acid, a likely carcinogen more commonly called PFOA.

Newport found a level of 2.23 parts per trillion of PFOA in the purified drinking water being piped to area homes and businesses. 

The results were surprising to A.J. Newhall, the superintendent of the Newport Water District, because a test of the source of water for the town showed no discernable level of PFOA. The state doesn’t require it, but he went a step further to test Nokomis Pond, which supplies water to 650 connections in Newport and Palmyra. 

It means it’s possible the water district accidentally introduced the chemical or the result is a mistake. Newhall plans to test the drinking water again in case the original sample had been cross-contaminated.

There are many ways people collecting water samples, which are then sent to laboratories for analysis, can accidentally introduce PFAS. For instance, if they used a moisturizer, deodorant or sunscreen they didn’t know had PFA: recently ate prepackaged food or fast food; wore clothes that were waterproof, stain resistant or laundered with fabric softeners; wore latex or vinyl gloves; used recycled paper towels; or came into contact with pumps or tubing that contain Teflon or other fluoropolymer-containing materials, according to the state’s drinking water program.

Newhall has wondered if the Teflon tape — used to wrap the threads of a pipe to seal two pipes together — contributed to the contamination. He and other water district operators have likely each used the tape thousands of times when repairing and installing pipes, he said. Homeowners and plumbers commonly use it as well. 

While the tape is applied to pipe fittings, rather than on the inside of the pipe where water flows, it is possible for the tape to flake off and enter the system, Newhall said. It’s not clear if it is contributing in a meaningful way to contamination, but it’s a possibility, he said.

There is no certainty the water supplies are free of toxic PFAS given laboratories can't entirely rule out their presence.
Teflon tape is used to wrap the threads of a pipe to seal two pipes together. Credit: Linda Coan O’Kresik

MacRae agreed, noting that the Teflon tape would likely not be a major source of PFAS given that it probably wouldn’t continually have contact with the water. 

“There could be a ton of things right in their office or in their environment that are releasing some PFAS chemicals,” MacRae said. “These levels are super low. It’s so easy to get contamination.”

Newport’s PFOA result of 2.23 parts per trillion is just barely high enough for many laboratories to reliably detect. Test results usually become far less accurate below about 2 parts per trillion.

“You’re looking at a medicine dropper of water in a football stadium,” Newhall said.

Maine limits PFAS in drinking water to 20 parts per trillion. It counts six different types of PFAS — alone or in combination — toward that temporary standard. 

Newport’s drinking water also had a different compound, perfluorobutanoic acid, or PFBA, at 2.76 parts per trillion; the raw water from Nokomis Pond tested at 2.3 parts per trillion for PFBA. But PFBA is not one of the six chemicals that counts toward the state’s standard. That’s because PFBA doesn’t appear to accumulate in tissue as much as other PFAS, MacRae said. 

Head north, and Dexter also discovered PFAS: precisely 2.62 parts per trillion of PFOA. The Dexter Utility District gets its water from Lake Wassookeag, and maintains 939 service connections that serve approximately 2,200 people.

Even farther north, Patten also discovered PFAS in its drinking water, which comes from two gravel-packed wells. One well had no detectable PFAS. The other had 4.43 parts per trillion of the compound perfluorooctanesulfonic acid, or PFOS, and 2.23 parts per trillion of PFOA. The combined sum of 6.66 parts per trillion meets the state standard but exceeds the federal recommended level.

It was the second time Patten had tested the contaminated well. The first test, conducted in February, also found similar levels of the chemicals.

It’s not clear where the chemicals are coming from, said Kevin Noyes, Patten’s public works director who oversees water and wastewater operations. The wells are roughly 2,000 feet apart, and the one with the chemicals is located in the middle of town, he said.

At this point it’s not clear what to do, Noyes said. The town’s water system currently serves 129 residential properties, 17 commercial properties and three nonprofit properties. He plans to test again in the future and wait for state guidance. 

The state, in turn, is waiting for further instruction from the federal government. The EPA is developing regulations for PFOA and PFOS in drinking water, and anticipates finalizing them by the end of 2023.

In the meantime, the EPA updated its interim health advisories for specific PFAS in June. It recommends that people’s exposure through drinking water supplies to PFOA not exceed 0.004 parts per trillion over the course of their lifetime, to avoid potential health problems. It said people should limit PFOS exposure to 0.02 parts per trillion. 

It made these determinations even though it’s not possible to accurately measure the presence of the chemicals in drinking water supplies below roughly 2 parts per trillion.

Many things can interfere with laboratories getting an accurate result at such low levels, MacRae said. PFAS might be in the air when someone opens a vial to collect a sample, making the result appear greater than it really is. Or PFAS that is actually in the water might bind to other particles and get filtered out, making the result appear lower than it really is.

Because of this, the EPA recommends communities and water systems that find any level of PFOA or PFOS inform their customers and consider taking actions to reduce the contamination, such as by installing treatment technologies or finding new uncontaminated drinking water supplies. 

Homeowners may also consider certified in-home water treatment filters, according to the EPA.

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Erin Rhoda

Erin Rhoda is the editor of Maine Focus, a team that conducts journalism investigations and projects at the Bangor Daily News. She also writes for the newspaper, often centering her work on domestic and...