What you need to know about 'forever chemicals' in Maine's soil

May 21—Toxic substances known as "forever chemicals" have been found in high levels in wells and farms across Maine. This class of chemicals, which has been linked to a number of chronic illnesses, has entered the Maine food system.

An unusual property of these substances that poses a risk to the Maine ecosystem is the fact that PFAS, or per- and polyfluoroalkyl substances, never really go away — hence the nickname "forever chemicals."

The Legislature is considering a package of bills to address "forever chemicals" in the state's soils and water. For the average Mainer, the issue of PFAS might seem distant, but it is immediately impactful, and the chemical is almost impossible to avoid without proper regulation.

Understanding PFAS

PFAS is a class of chemicals, including perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), found in everything from non-stick pans to waterproof jackets to firefighting foam.

"From a scientific perspective these chemicals have some really unusual properties," said Andrew Smith, a state toxicologist at the Maine Center for Disease Control and Prevention. "Just think of a chemical that has been made to be both resistant to oils and resistant to water which makes them work so well. That makes them behave in unpredictable, unusual ways in the environment."

"It's true that they're very, very persistent," Smith said. "They're not going to degrade very fast in the soil. They are eliminated from our bodies, but slowly for some of them."

They also have the ability to travel through different media — for example, from soil to milk to your body's tissues — unlike other chemicals that have caused concern in the past.

"Compared to dioxin, PFAS travels fast in groundwater, travels into milk, travels into fish as well as potentially in food packaging," said Tom Simones, a state toxicologist at the Maine CDC. "You can get different routes of exposure there that's one thing to consider and just to add to the toxicity point of view it seems these chemicals are impacting multiple systems [in the human body]."

PFAS have become strongly linked to health problems like liver damage, thyroid disease, decreased fertility, high cholesterol, obesity, hormone suppression and cancer.

"We increasingly understand its toxicity and its potential for harm," said Patrick MacRoy, deputy director of Defend Our Health, a nonprofit advocacy group working on issues of clean and safe food and drinking water in Portland. "That's what's really troubling, is scientists are showing it to be harmful at very low levels. PFAS is a group of a large number of chemicals. The more and more science that's coming out, the more we're seeing potential problems from many members of the class."

Jeffrey McBurnie, director of compliance at Casella Resource Solutions in Hermon, said there are limitations to the current science around PFAS.

"Because it is not ethical to have directed, scientifically structured health studies on humans, we have to rely on either human health studies on industrially [affected] populations or use animal laboratory studies," McBurnie said. "While it is fortunate that there are not multitudes of these opportunities, it is unfortunate in that there is no opportunity to replicate them or to eliminate other health influences [like] diet [and] smoking."

McBurnie said that this often results in "overly conservative exposure limits when applied to a chemical exposure risk assessment."

McBurnie said that PFAS chemicals like PFOS and PFOA have already been voluntarily removed from most American manufacturing. However, most of the PFAS we're seeing now comes from the cleaning of carpeting and furniture, fabrics, non-stick cookware and other products that use PFAS to create a specific product characteristic like water resistance.

"These discharges are coming primarily from residential wastewater customers as a result of normal, everyday household activities," McBurnie said. "We also know that PFAS compounds can be airborne, which accounts for an almost universal presence of PFAS in the environment."

Smith also said that according to data from the U.S. Centers for Disease Control and Prevention, the average levels of PFAS in Americans' blood has dropped dramatically over the past decade or so.

Despite this information, Smith said that there is still so much we don't know about PFAS.

"We keep finding it in new places," Smith said. "We just don't yet have a sense on how widespread this is going to be."

Sharon Treat, senior attorney at the Institute for Agriculture & Trade Policy, noted that even as industries restrict the use of certain PFAS chemicals, scientists find that others are equally concerning.

"Every time we have one of these hearings scientists show up to testify PFAS compounds that exist," Treat said. "A couple years ago, it was 3,000 to 4,000 compounds. At the latest hearing, there were 9,000 compounds. It's in so many products and continues to be put on the market and new versions continue to be made. It seems to be a ballooning issue that is going to take all hands on deck."

Another unknown: how to dispose of PFAS.

There are water filtration systems for wells that will get it out of the water, but as for destroying the chemicals once they are out or removing it from the soil, science has not provided a conclusive solution.

"It's an area where there's a lot of research," MacRoy said. "In a controlled lab sense, you can get it hot enough that it does break down but we're talking about really tiny amounts of it in sludge or other things [but] it's hard to actually do that on an industrial scale. There's technology that's in development that scientists are looking out to make it more effectively break it down, particularly when it's mixed in with other stuff, but at this point there's no effective way."

In the garden and the home

Home gardeners in Maine may also be concerned about PFAS in their soil. On top of the potential for PFAS presence in home garden soil and water, many commercial compost and fertilizer products have PFAS in them as well.

Industry leaders like McBurnie said that composts made with bio-solids in Maine are vetted through the Maine Department of Environmental Protection's "rigorous testing and approval process," and composts that have PFAS in them must adjust their use recommendations accordingly. However, the companies are still allowed to use municipal sludge, or "biosolids," in their products.

Gardeners that may have applied such products or live in areas surrounding sites with known PFAS can get a soil test and the Maine CDC can explain the results, Smith said. It will be costly, though. Since there are no labs in Maine that test for PFAS, gardeners have to pay for shipping out of state, as well as the cost of the test.

"The most impactful step that the average Mainer can take is to modify their consumer behavior to avoid purchasing or using PFAS-containing products in their household," McBurnie said.

However, Treat said that avoiding such products can be difficult as a consumer because companies do not have to tell you if their products contain PFAS.

One of the bills before the Legislature, LD 1503, would phase out the use of PFAS in consumer products unless absolutely necessary, and would require manufacturers to disclose whether their products contain it.

Until then, consumers will have to rely on databases like those from the Environmental Working Group in order to know which products to avoid.

"To some extent you can try to buy only PFAS-free products but at this point it's hard to know what those are," MacRoy said. "It's not required to be labeled. The best solution is to try to address this on a societal level and implement policy that gets it at its source. It's just too difficult to shop your way out of it."