Maine faces a widespread contamination due to PFAS, “forever chemicals” in ubiquitous use and now polluting wells, public water supplies, farmland and food chains.

The “Invisible and Indestructible” series explores the pathways by which PFAS cycle through Maine’s environment and the far-reaching repercussions these enduring chemicals will have.

Outlined below are answers to 10 common questions about PFAS. Read part one of the series: Compound Injustice: PFAS may concentrate over time in landfills near the Penobscot Indian Reservation.

Why is exposure to PFAS a concern?

Toxicological research shows that per- and polyfluoroalkyl substances (PFAS) can disrupt hormonal, immune and reproductive systems, and can increase the risk of various cancers. In June, the U.S. Environmental Protection Agency (EPA) dropped its drinking water “health advisory level” for two of the most common PFAS chemicals, PFOA and PFOS, to close to zero, levels too minute for current technology to detect. Yet some exposure to these chemicals is virtually inescapable now; a federal CDC report found 97 percent of blood samples taken from Americans contained PFAS.

What are PFAS chemicals in?

One needn’t look far to find materials containing PFAS. They’re in construction products (such as paints and sealants), electrical equipment (like coated wires), printing and photographic materials, metal coatings, firefighting foam, ammunition, boatbuilding and automotive products, pharmaceuticals and medical supplies, ski wax, artificial turf and countless household products — cleaners, adhesives, polishes, pesticides, food storage (such as takeout containers and fast-food wrappings), nonstick cookware, outdoor gear, electronics, stain- or water-resistant furnishings (like couches, mattresses and carpeting) and even some clothing and personal care products, Maine is among the first states to start mandating disclosure of PFAS in products, slated to take effect in January (unless an effort by trade groups to delay the measure succeeds). 

How are PFAS chemicals getting into waters?  

Commercial and residential uses of PFAS contribute some chemicals to wastewater, but a larger portion likely comes through manufacturing. In Maine, PFAS are or have been used in industrial production of grease- and water-resistant paper and paperboard, leather products, shoes, textiles and semiconductors. Historic use of fire-fighting foam (specifically designed for petroleum fires) has also led to groundwater and surface water contamination. PFAS are now so ubiquitous in the water cycle that they are falling in rain.

Why are they called “forever chemicals”?

PFAS persist indefinitely in natural systems and accumulate within bodies for years. “Persistence is the key factor that lets pollution problems spiral out of control …,” wrote a team of international scientists. “(It) enables chemicals to spread out over large distances, causes long-term, even lifelong exposure, and leads to higher and higher levels in the environment as long as emissions continue.” While other pollutants — such as dioxins and PCBs — are also persistent, there are far fewer of those compounds. PFAS, synthetically manufactured chemicals with extremely strong carbon-fluorine bonds, number at least 12,000. Most research has focused on fewer than 100 PFAS compounds, and even in this small subset, the ecological impacts, physiological effects and potential health concerns differ markedly.

Why are PFAS so prevalent in Maine and not elsewhere? 

Water activist Erin Brockovich reports that Maine has some of the highest levels of PFAS water contamination she has seen in her work with communities around the country, possibly because this state is at the forefront of testing. PFAS are in global use and still actively produced, so no region will likely escape the ecological, economic and public health challenges. In the words of Jean MacRae, a University of Maine professor of civil and environmental engineering, “The more we look, the fewer places we’ll find without contamination.” 

Is the full extent of the contamination known? 

While states like Maine are actively testing to determine the extent of contamination, the scope of the testing is no match for the estimated 4,700 PFAS compounds in present or past commercial use. The Maine Department  of Environmental Protection assesses water samples for 28 PFAS compounds, but its interim drinking water standard only covers six.  Sampling protocols for commercial labs typically include 18 to 24 PFAS, said Linda Lee, a Purdue University environmental chemist, while research labs may sample up to 70 compounds. “Fifty to 70 percent of what I’m finding (in samples at Purdue’s lab) aren’t being tested by the commercial labs,” she said. She’s convinced that the PFAS evident in standard water testing are a small subset of what may be in soils or wastewater sludge. The sludge, she said, “could potentially have hundreds (of PFAS compounds).”

What’s Maine doing to address this crisis?

The short answer is a lot. The state government has moved with uncharacteristic speed to address PFAS contamination through many measures, including the world’s first staged ban on use of PFAS in most products (taking full effect in 2030), and a ban on the land application of sludge and sludge-based compost. State agencies are openly sharing data gathered on PFAS. Testing, research and policy demands diverted untold hours and resources from agencies that would otherwise be directing them toward other important challenges.

Did the manufacturers of these chemicals know they were problematic?

PFAS were first manufactured primarily by 3M and DuPont, chemical corporations known for PFAS coatings like Scotchgard and Teflon. They knew by the 1960s from their own lab tests that these enduring chemicals posed serious health risks, but continued to produce and market the “legacy” or long-chain PFAS (those with more carbon molecules). The corporations finally phased out two of the most common compounds: PFOA and PFOS, but in their place introduced short-chain replacements (what they termed “GenX” PFAS), with fewer carbon molecules, that were marketed as safer. Growing evidence indicates that these short-chain compounds are just as toxic, and more mobile and persistent in ecosystems. 

Why aren’t these products regulated to protect public health?

The EPA knew about the dangers of PFAS compounds by 2001, due to a 972-page public brief shared by attorney Robert Bilott, whose story of battling DuPont to get that voluminous evidence is documented in the film, “Dark Waters,” and his book, “Exposure.” The agency failed to take substantive action until recently. Last month, the EPA recommended PFOA and PFOS, two common PFAS chemicals manufactured for decades, for inclusion as hazardous substances under the federal Superfund program, but the agency has taken no action to phase out or ban production of PFAS. 

Is it possible to destroy these chemicals?

Any lasting solution to PFAS contamination depends on developing technology to destroy the chemicals, rendering them into harmless elements. Scientists are testing all sorts of techniques such as supercritical water oxidation, thermal regeneration, electrochemical degradation, ultrasonication, pyrolysis and ultraviolet-initiated degradation, but nothing has progressed beyond lab experimentation. Some methods are highly energy-intensive, and none could recapture all the PFAS now cycling through water systems, the atmosphere and soil ecosystems. There is no simple fix on the horizon. 

Clarification: this story has been updated to clarify the number of PFAS compounds the Department of Environmental Protection samples for assessment. 

This project was produced with support from the Doris O’Donnell Innovations in Investigative Journalism Fellowship, awarded by the Center for Media Innovation at Point Park University in Pittsburgh, Pa.