Every new study on PFAS contamination points to a frightening reality: The chemicals aren't just in household products, they're everywhere in our environment. Recent analyses have found PFAS — also known as "forever chemicals" — in 83% of sampled surface waters, 60% of sampled public groundwater wells and in the bodies of animals up and down the food chain. Freshwater fish from nearly every state have such elevated PFAS levels that eating them even infrequently can significantly increase exposure to the chemicals.
Meanwhile, the body of research that links PFAS exposure to adverse health outcomes — like endocrine disruption and cancer — and environmental degradation continues to grow, highlighting the urgency to stop producing the chemicals immediately. But even as regulators like the EPA are finally developing guidelines for how to handle PFAS contamination, slow responses from industry and unsettled science over how to remediate contamination mean that we'll be dealing with the fallout from forever chemicals for quite some time.
Where Does PFAS Contamination Come From?
PFAS, or perfluoroalkyl and polyfluoroalkyl substances, are a class of chemicals that impart non-stick, greaseproof and flame retardant properties to materials. This makes them appealing additives to a huge range of goods, from non-stick cookware to greaseproof food packaging to clothing to firefighting foams. When these products are manufactured or thrown away, they leach PFAS into soil and waterways. And because of their unique chemical structure, PFAS don't degrade in the environment like most other substances, earning them the nickname "forever chemicals."
Some of the biggest early discoveries of PFAS contamination occurred near airbases and other locations where firefighting foams were frequently deployed or stored. In these cases, the Department of Defense has spent billions on bottled water and water treatment systems to avoid excess exposures for its personnel. But as PFAS became more and more common additives to everyday goods, sources of contamination have also increased. Soil and water around manufacturing and disposal sites are all likely to have elevated PFAS levels and farmland can get contaminated via pesticides, where the chemicals are used in packaging or as surfactants that help distribute other chemicals evenly.
On an individual level, PFAS exposure can come from anything that's been treated with the chemicals, like cookware, textiles, furniture and carpets. Contact with food packaging, especially greaseproof materials, contributes to higher blood PFAS levels. They also settle in dust, where they pose a particular risk to children that might come into contact with it. Food itself can also be a source of PFAS when crops or animals were raised or caught in environments with high PFAS levels.
But it's the downstream accumulation of household and human PFAS exposure — treated wastewater and its byproducts — that have come under recent scrutiny. Processed solid material from sewage treatment, called biosolids, have been a widely used fertilizer for decades. Never uncontroversial, biosolids have long raised concerns about pathogen spread and pharmaceutical disposal, but the EPA has generally signed off on their use. In recent years, however, mounting awareness of PFAS in water supplies led to the realization that wastewater and biosolids were laden with PFAS, meaning that farmland fertilized with biosolids could also be contaminated.
So far, studies have shown that soil with a history of biosolid application can be contaminated with PFAS to depths of at least 9 meters, with PFAS present in deeper groundwater, too. In Maine, analysis of contaminated soils and groundwater led officials to start testing milk and other products. They discovered many were well beyond safe thresholds for PFAS consumption. As testing has expanded, many farms across the states have essentially stopped operating. With biosolid application in common practice around the country, it's nearly certain that other states have similar problems, but Maine's ballooning contamination crisis has led many farmers to be wary of testing their own land.
Why is Environmental PFAS Contamination Risky?
Because of their unique chemical structure, PFAS were originally marketed as functionally inert. Today, scientists have shown that's far from the case: PFAS exposure damages immune systems, lowers vaccine effectiveness, causes liver damage, disrupts thyroid function and increases the risk of certain cancers. Emerging research documents that these harms are especially acute for children, because disruptions to metabolism and endocrine pathways can cause growth delays and abnormalities. These impacts are especially pronounced when people are exposed to multiple PFAS varieties, a near certainty given the ever expanding list of PFAS that show up in environmental monitoring.
From an environmental perspective, the chemicals are just as risky. They cause many of the same problems in animals as they do in humans and their tendency to bioaccumulate — increase in concentration as they move up the food chain — means they pose a particular risk to already vulnerable species of fish and mammals in the ocean. PFAS in soils are tenacious and have the potential to contaminate plant material for many generations as plants take up the chemicals from their roots and release them again when they decompose. Meanwhile, PFAS in water are extremely mobile and rather than simply accumulating in the ocean, can make their way back into the water cycle from sea spray and redistribute over a wide area in rainwater.
What are Governments Doing About PFAS?
Even as it becomes clearer that PFAS contamination is both more ubiquitous and more harmful than originally thought, federal and state governments have been slow to respond. In a situation that parallels the agency's approach to pesticide regulation, a long-term pattern of deference to the chemical industry means that the EPA isn't well equipped to do its own detailed risk assessments and so even as medical journals publish more and more research pointing to the role of PFAS as potent endocrine disruptors, response from the agency has been inconsistent and slow.
Despite early recognition that many PFAS could leach into food, it took the EPA until 2002 to begin the process of regulating some of the worst offenders, when it mandated that manufacturers disclose using certain PFAS, but the timeline for action didn't match the urgency of the problem. Even when voluntarily phasing out some of the worst PFAS, manufacturers have replaced well-researched chemicals with other PFAS that have less-understood health impacts. These chemicals had little trouble jumping through the hoops required by the FDA to get approved for use in food packaging, leading to the wide array of PFAS we see in products today.
Unsurprisingly, the anti-regulation Trump administration failed to take effective action on PFAS and even set a proposed safety limit for the chemicals, 70 parts per trillion (ppt), that was dramatically above levels researchers considered safe. The Biden administration has taken PFAS more seriously, releasing a proposal in March 2023 that would cap the most common PFAS in public water supplies to 4 ppt, far less than the earlier limit, but still a compromise from safe levels. However, it's one thing to have goals and another to meet them; without serious infrastructure investment, most public utilities can't test for PFAS effectively, let alone filter them out of water.
Meanwhile, some state governments have taken more aggressive action to curb PFAS production. California recently passed bills banning the sale of cosmetics containing PFAS, phasing out PFAS use in textiles and mandating PFAS disclosure for all products and ingredients entering the state. It also dedicated resources to monitoring PFAS levels in waterways, with a focus on the underserved communities that tend to have higher levels of PFAS because of their proximity to manufacturing and waste disposal sites. New York recently banned PFAS in clothing and food packaging, joining similar legislation from Maryland and Oregon, while Pennsylvania and Rhode Island both have introduced their own water monitoring standards and limits for the most common PFAS varieties.
But by far the most stringent PFAS legislation comes from Maine, where a progressive statewide ban on the products started in January 2023. Aiming to completely eliminate PFAS from all products by 2030, the regulation is a response to Maine's acute on-farm PFAS crisis and growing concern about their impact. But the state isn't stopping there: The attorney general's office is suing two of the biggest PFAS manufacturers, DuPont and 3M, alleging they knew the risks associated with PFAS manufacturing but continued to produce and market them long after those risks became apparent.
Are We Too Late?
As governments finally begin to monitor PFAS levels, it's increasingly clear that the most important thing to do is stop producing them immediately. But for places like Maine that have begun to look hard at their PFAS problem, there's an unanswered question of what to do with the PFAS that are already in the soil.
No industrial contaminant is good news or easy to deal with, but most aren't as tenacious as forever chemicals. There's an array of techniques agencies like the EPA can use to clean up and contain environmental contaminants, like capping them off with impervious materials, treating or neutralizing them with other compounds or simply limiting access to areas while contaminants break down. Unfortunately, the science on how to remediate PFAS contamination is still sparse. Removing PFAS from water is possible, since they can be filtered out and contained with fairly common (albeit expensive) techniques on a municipal scale, but removing PFAS from soil is significantly more difficult, relying on techniques that are prohibitively expensive or that leave secondary contaminants.
On some contaminated land, there might be enough potential development money to make the current remediation techniques worth their high cost. But for farms, especially the dairy farms in Maine that were already barely breaking even, the current remediation strategies are laughably out of reach.
Still, farmers and researchers haven't given up and are even looking at the crisis's main problem, contaminated crops, with a silver lining. Since crops are clearly pulling PFAS out of contaminated soil, researchers are investigating whether they can be used efficiently enough to treat land through a process called phytoremediation. It's a proven technique for some environmental contaminants like heavy metals, but with so many questions unanswered about how long treating soil could take and what to do with contaminated plants, it's not the ready-to-use solution farmers need.
In the meantime, farmers affected by contamination need support to survive. The Maine Congressional delegation introduced the Relief for Farmers Hit with PFAS Act, which would give financial assistance to farmers and extend testing capacity across the country, along with bolstering research on remediation strategies. As Maine Senator Susan Collins stated, "This is not just a problem in Maine — PFAS contamination has been discovered on farms across the country and this problem will only become more evident as testing becomes more readily available." With PFAS production still not in the rear view, addressing PFAS contamination on farms across the country is shaping up to be a lengthy and expensive endeavor.
