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By the end of this year, the Environmental Protection Agency has promised to propose new national drinking water standards for PFOA and PFOS, two of the most studied pollutants among the thousands of compounds known as PFAS, or, more colloquially, “forever chemicals.”

PFAS are man-made chemicals associated with nonstick pans and firefighting foams, but they are also used in things like cosmetics, paper straws and takeout containers, and waterproof fabrics. The same properties that make them useful for these applications also make them incredibly resistant to degradation, which means they pile up in the environment and in people’s bodies, vastly increasing the risk of cancers, birth defects, decreased immunity, and many more health problems.


The health threats are not just in the drinking water of people who live near chemical plants or military bases, where PFAS-containing firefighting foams are used. A 2022 analysis of 114 waterways across the country by the Waterkeeper Alliance found that 83% of waterways contained PFAS, in some cases at concentrations thousands of times higher than the EPA’s drinking water guidelines. And a 2007 study showed that over 98% of Americans had detectable levels of PFAS in their blood, regardless of demographics.

Ultimately, setting a standard for two of the thousands of PFAS compounds is a win for public health. But whatever rule the EPA proposes will be contentious — either too high to convince environmentalists that it sufficiently protects human health, or so low that water treatment plants, which will be on the hook for implementing the rule, will protest the expense of doing so.

Many water regulation and treatment experts argue that the PFAS pollution problem should have been taken care of a long time ago. The Toxic Substances Control Act of 1976 was intended to regulate chemicals that posed a threat to human health. Forever chemicals, however, were not among them. The reason? The companies that originally made PFAS — the acronym stands for per- and polyfluoroalkyl substances — were supposed to report to the EPA that according to their own internal research, the chemicals had horrible health effects. But the companies didn’t report their findings — for decades.

The PFAS problem then fell through the safety nets of the Clean Air Act and the Clean Water Act. Because no one knew how bad these toxins were until they were already everywhere, both laws couldn’t — and still can’t — regulate how much PFAS is released into rivers, lakes, and the atmosphere.


Now it’s down to the Safe Drinking Water Act and water treatment plants to keep PFAS out of Americans’ tap water. Almost any regulation the EPA proposes would require water utilities to implement expensive new treatments, methods that one expert jokingly referred to as “space-age technology.”

Environmental advocates want the EPA to set limits on PFOA and PFOS that are as low and as protective of health as possible. Water treatment operators say they also want to protect health, but they don’t want the implementation of this rule to drain their budgets. What they both agree on is that polluters should pay for the expensive mess they have created.

Why remove PFAS from water?

PFAS manufacturers obscured what they knew about the compounds’ dangers for decades, even as they dumped it into landfills and waterways, leaving the EPA and communities scrambling to catch up. In the late 1990s, Rob Bilott, a corporate defense attorney, uncovered the DuPont chemical company’s decades-long poisoning of the water in Parkersburg, W.Va., with one particular PFAS compound, called perfluorooctanoic acid or PFOA, used in manufacturing Teflon. The case was later chronicled in a profile of Bilott in The New York Times, in an autobiography, and in a 2019 movie starring Mark Ruffalo. More recently, the Minnesota Reformer reported last week that 3M knew for decades that the PFAS it was dumping east of St. Paul was toxic. In 2018, 3M company settled a lawsuit over the pollution, agreeing to pay $850 million to help with a cleanup. 3M maintains that its chemical has no harmful effects on the environment or people’s health, but in an announcement on Tuesday, the company said it will stop manufacturing PFAS by the end of 2025.

Studies conducted as part of a settlement in a class-action lawsuit against DuPont found “a probable link” between PFOA and six different conditions: pregnancy-induced hypertension, kidney cancer, testicular cancer, thyroid disease, ulcerative colitis, and high cholesterol. Other studies conducted since then have only made the links between PFAS exposure and negative health effects clearer.

Loreen Hackett, founder of PfoaProjectNY, has been sharing health studies of PFAS online since 2016, a couple years after elevated PFAS levels were found in the industrial town of Hoosick Falls, N.Y., where she lives. “When I first started it, it was one [study] every month or two,” she said. “Now it’s weekly.”

The research findings prompted the EPA over the last 13 years to lower its guidelines for the recommended maximum level of PFOA in drinking water by 10,000-fold, dropping it in 2016 to 70 nanograms per liter from 400 nanograms per liter, and then in 2022 to 0.004 nanograms — such a low concentration that the EPA acknowledged that its own technology could not detect it. The agency’s health advisories, however, are non-enforceable guidelines, not regulations for how much of a contaminant is allowed in water.

Still, the science behind the advisory limits will inform the EPA’s upcoming enforceable regulations. But marrying the EPA’s opinion of safe PFAS levels to the levels that water treatment plants can achieve is tricky. PFAS aren’t easily removed by traditional water purification techniques and need more specialized treatments, of which three techniques have emerged as frontrunners: granular activated carbon (GAC), ion-exchange resins, and reverse osmosis.

GAC is a very porous, high-surface-area filter material derived from organic matter such as coal, wood, or coconut shells. In the same way a towel can wick off more moisture than a smooth bed sheet, GAC’s many pores create places for pollutants to dock. While PFAS compounds like PFOA and PFOS, with long carbon chains, can be trapped on GAC, shorter-chain varieties of PFAS are harder to capture. Ion-exchange resins, which operate similarly to water softeners, work well for filtering out PFAS specifically, but are more expensive to maintain than GAC. Most expensive and energy-intensive is reverse osmosis, which uses a pressurized membrane to filter out pollutants regardless of their properties and thus is best for all kinds of PFAS and other pollutants.

Which technique is best for a particular water treatment plant depends on many factors, so operators are anxiously waiting to see what rule the EPA will propose.

What might the proposed guidance look like?

In deciding how to regulate PFOA and PFOS, the EPA has two options under the Safe Drinking Water Act. One of those options is a so-called treatment technique rule. When there’s no feasible way to measure a contaminant at a level low enough that EPA does not expect health concerns, the agency can instead mandate treating water with a prescribed technique. This is the approach for lead and copper, of which the EPA says there is no safe level. When lead or copper levels in consumers’ water are above a certain measurable threshold, it triggers the water utility to use the prescribed treatment.

“I think we’re at a point where [it’s] hard to say that there would be actually a safe level for exposure to [PFAS],” said Anna Reade, a senior scientist at the Natural Resources Defense Council. Reade pointed out that there isn’t much research on the health effects from exposure to mixtures of PFAS compounds — of which there are more than 12,000. “A treatment technique could be set in a way that would address more than just PFOA and PFOS,” she said, offering added protection.

Installing a treatment like GAC would also have the co-benefit of filtering out many other pharmaceuticals, pesticides, and personal care product ingredients that haven’t been regulated, as well as other PFAS whose level of toxicity is still unstudied. To avoid this whack-a-mole approach to regulating one PFAS at a time, experts say the EPA could also regulate the entire class of PFAS compounds at once, which the agency has acknowledged.

The alternative approach would be for the EPA to set both a maximum contaminant level goal, or MCLG — a level of pollutant at which there is no known risk to health and that would be the regulatory limit in an ideal world — and an associated maximum contaminant level, or MCL, a more realistic and enforceable standard. The EPA tries to set the enforceable MCL as close to the MCLG as possible, but the difference between the values takes into account cost and the abilities of the best available technology. Even though the MCLG for carcinogens (the EPA has agreed that PFOA is a “likely carcinogen”) is traditionally set to zero, Chris Moody, a regulatory technical manager for the water utility society the American Water Works Association, said he and other engineers prefer the maximum contaminant goal and maximum contaminant level approach over a treatment technique approach, because it gives water utilities the freedom to choose the treatment that’s right for their site.

Give a number to meet, he said, “and let me hit that [the way] I hit that. So if I need to get down to 10, let me get to 10 however I’m going to do it. That way, I know I’m below 10, I’m good.”

Hackett, who advocates for PFAS legislation both in New York and on a federal level, said she was “cautiously optimistic” that the EPA could justifiably set a MCLG of zero and a MCL of 5 nanograms per liter or lower, which is a level that labs can reliably measure. One of the criticisms of the health advisories the EPA released this summer was that the 0.004 ng/L level for PFOA was below detectable levels, which means that if it were set as the MCL, simply being able to figure out whether the water was meeting the standard would be a huge barrier to water plants being able to comply with the rule.

Water treatment plants are hesitant

Water treatment facility operators are also worried that mandating an overly specific treatment might force plants to put technology in place that is doomed to become obsolete if regulations are instituted for other, harder-to-remove PFAS contaminants. Balancing protecting customers’ health and complying with rules is hard on an already-tight budget, where every dollar has to be reallocated from another program or raised through rate hikes, said Moody.

“Unfortunately it’s easier to calculate cost of treatment, of complying with a drinking water standard, than it is to accurately calculate the benefits of treating water,” said the NRDC’s Reade. “How do you quantify lowering the risk of cancer and of immune effects and reproductive effects and developmental effects? What is the benefit in terms of a number that you could compare that to in terms of the cost of doing cleanup?”

Moody said price is a big part of the equation for water utilities, because their budgets aren’t only covering the installation of new technology, but are supposed to also do things like replace aging service lines, many of them lead pipes.

“I try to explain it as you’re a starving college student and you’ve got $100 a month you can spend on whatever you want to spend it on,” he said. “If your car has to go to the shop … you’re going to be told by the mechanic to do all these other things like replace your air filter, but if your tire’s blown out, you have to replace the tire.”

However, Hackett of PfoaProjectNY said, “There is more money out there now available to water utilities than has ever been,” whether it’s through grants, the EPA, state drinking water revolving funds, or funds for military site cleanup in the Department of Defense budget.

“The money is there,” she said. “But clearly public health is not the top priority.”

‘Utilities and their ratepayers shouldn’t end up having to pay the bill’

GAC filters are the most likely option under a potential treatment technique rule, and water treatment plants are worried about them. GAC beds take up a lot of space and many facilities are space-constrained, often because cities and towns have grown around them, said Moody. GAC also might not be the best choice for every plant depending on the characteristics of the source water, which might contain substances that will gunk up the GAC filter and force them to change out the activated carbon more often. Carbon changeouts drive up the cost of operation, which is also modulated by how close to zero the EPA sets the acceptable PFAS level — every nanogram means a more frequent granulated activated carbon or ion-exchange resin changeout and thus more money.

Carel Vandermeyden is the director of treatment/engineering services administration at the Cape Fear Public Utility Authority in Wilmington, N.C., a town downstream from a Chemours plant that manufactures a PFOA replacement called GenX. Chemours, a DuPont spinoff company, dumped GenX — also a PFAS with unknown health effects — into the Cape Fear River. After the pollution was discovered in 2015, the Cape Fear Public Utility Authority evaluated their treatment options and ultimately decided to install GAC beds.

“We looked at it from a [perspective that] our customers had been exposed to this pollution from this upstream industry for decades,” said Vandermeyden. “And rather than waiting on EPA standards to come out for a family of compounds that are in the PFAS suite of compounds, we felt it was, from a public health perspective, more important to implement the best available technology that we know of now, in order to protect our customers.”

The GAC beds cost $43 million to install and have operating costs of $3.7 million for the first year and $5 million each year after. This amounts to a $5 per month increase on an average customer’s bill, which doesn’t sound like much, but is hard for customers on a fixed income, Vandermeyden said. The utility is suing Chemours to recoup their costs.

It’s upstream polluters that should be responsible, Vandermeyden said. “It shouldn’t be utilities and their ratepayers that end up having to pay the bill on this.”

This was never supposed to happen

The EPA regulation for PFOA and PFOS falls under the Safe Drinking Water Act, which is the domain of municipal water treatment plants. But water treatment plants were never supposed to have to deal with reducing pollutants to such low levels because the pollution was never supposed to reach these facilities in the first place, at least in theory.

“The way we see it is the role of Safe Drinking Water Act should be really a last effort when we’ve failed other places,” said Moody. “It doesn’t make a lot of sense to us that we’re constantly having to do new drinking water rules to address failures other places, particularly with source protection.”

Betsy Southerland, former director of the Office of Science and Technology in EPA’s Office of Water, said the Clean Water Act and the Safe Drinking Water Act are supposed to work together, though the partnership is buried in the details. The Clean Water Act is supposed to protect the surface waters that drinking water gets pulled from, like rivers, lakes, and streams. Under the Clean Water Act, when the EPA sets a human health standard for a pollutant, states can use that number to create a pollution budget. From that budget, they can apportion permits for those releasing that pollutant to limit pollution in that body of water. However, the EPA still hasn’t set human health standards for PFAS, and there isn’t a federal standard for those PFAS release permits.

“At this point, we haven’t seen anything under the Clean Water Act aside from a couple of guidance memos,” said Moody.

At this point, the Safe Drinking Water Act and the national array of water utilities are the only things standing between consumers and the PFAS in their tap water.

Lawsuits — whether filed by individual utilities or by states — are one way to get polluters to pay, Reade said. Earlier this year, the EPA proposed naming PFOA and PFOS hazardous substances under the Superfund law. This proposal, still under review, would give the EPA pathways to hold polluters accountable for cleanup.

But cleanup only goes so far, said Hackett, who describes the 7,000-person greater Hoosick Falls area as having been “Chernobyl’d,” with one federal Superfund site, three state Superfund sites, and five more under investigation. “I mean, you can’t dig up all Hoosick Falls 40 feet down and give everybody new dirt, you know?”

Advocates say that PFAS needs to be banned from non-essential uses and new systems need to be instituted to catch future pollutants more quickly. Southerland pointed out that the National Defense Authorization Act of 2020 directed the National Institute of Environmental Health Sciences to put together an emerging contaminants list, a process that might move faster than the Safe Drinking Water Act system and might catch future pollutant problems earlier. But for now, these are the tools the EPA has.

“It’s kind of hard to believe that in this day and age that we had to deal with this particular situation, with having a pollutant introduced into our source water,” said Vandermeyden. “Even though we have the Clean Water Act and the Safe Drinking Water Act already established for many, many years, yet it was still possible to have a compound introduced like PFAS.”

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