Last week, the federal Environmental Protection Agency issued a health advisory, warning that extremely low levels of certain types of PFAS can be dangerous to human health.
The chemical class, commonly found in consumer products, has been discovered in dozens of public and private drinking water supplies in Vermont.
“The updated advisory levels, which are based on new science and consider lifetime exposure, indicate that some negative health effects may occur with concentrations of PFOA or PFOS in water that are near zero and below EPA’s ability to detect at this time,” the advisory said.
Though Vermont’s drinking water standard for PFAS is stricter than those in many other states, it allows higher levels of PFAS in water supplies than what the EPA now considers safe.
Julie Moore, secretary of the Agency of Natural Resources, said the state is reviewing the EPA’s advisory and how best to align the state’s response with the new guidance.
“We take this information incredibly seriously and are committed to moving quickly and thoughtfully” to protect the public from exposure, Moore said.
While the latest health advisory does not set regulatory limits for drinking water, Moore expects the EPA to release federal drinking water standards before the end of the year. The state’s standards will either need to meet or be stricter than those standards.
Vermont’s legal limit for a combined five PFAS chemicals is 20 parts per trillion, and a previous EPA health advisory recommended keeping combined levels of PFOA and PFOS to less than 70 parts per trillion.
The EPA’s new “interim” health advisory for PFOA, or perfluorooctanoic acid, is much smaller at 0.004 parts per trillion. For PFOS, or perfluorooctane sulfonic acid, the advisory level has been updated to 0.02 parts per trillion.
The agency also issued two advisories for chemicals that have been considered replacements for PFOA and PFOS — GenX chemicals (10 parts per trillion) and PFBS (2,000 parts per trillion).
Federal and state officials have long known that PFAS, or polyfluoroalkyl and perfluoroalkyl substances, are linked to harmful health impacts such as thyroid problems, infertility, and some types of cancer. PFAS, which are often called “forever chemicals” because they don’t naturally break down, are commonly found in stain resistant and water repellant consumer products, food packaging and even in food itself.
Vermont’s highest profile case of PFAS contamination played out in Bennington starting in 2016, when state officials discovered PFOA contamination in a 26-square mile area, impacting about 8,000 residents. A now-shuttered Teflon plant had emitted the chemical into the air from its smokestacks. Many residents nearby have high levels of PFOA in their blood, and some have developed cancers and have even died, though it’s impossible to conclusively link their illnesses to the contamination.
The case spurred sampling efforts by the state, which started in 2016 and expanded in 2019 following the passage of state legislation, said Ben Montross, drinking water program manager for Vermont’s Department of Environmental Conservation.
While no other Vermont town has seen contamination like the Bennington case, high levels of the chemicals have shown up in water bodies, landfills and drinking water sources around the state, sometimes for unknown reasons.
PFAS is ubiquitous in the environment. When state officials have collected background soil tests, they have found concentrations of at least two parts per trillion — the smallest detectable amount — “essentially everywhere,” Moore said. While they haven’t found the chemicals in many lakes and rivers, their technology may not be able to detect such small amounts.
Residents in the Northeast Kingdom and Canada have expressed concern about PFAS detections in Lake Memphremagog, a drinking water source for 175,000 Canadians. Wastewater treatment plants that treat leachate from landfills have had high readings of PFAS, and citizen groups in the state have found PFAS in water bodies, as well. Recently, the state asked South Hero to more closely analyze PFAS at its closed landfill after finding contamination there.
The state maintains a public database of drinking water sources with PFAS monitoring results.
Montoss said PFOA and PFOS has been detected in 81 public drinking water sources in the state. Of those, 19 detections were above the state’s limit of 20 parts per trillion.
When a system exceeds the state standard, it issues “do not drink” notices to its users, and then the system must address the problem. Typically, that means hiring an engineer to explore state-approved alternatives, such as using another water source if it’s available or treating the water for PFAS.
“There's, give or take, 60 other systems that have not have not yet addressed PFAS because they haven't exceeded the (state’s maximum contaminant level),” Montross said, even though some level of the chemicals have been detected there.
The health advisory presents the state with some challenges as officials consider how to move forward and potentially adopt new standards.
“There are toxicologic models that health experts, including our own at the Health Department, rely on in calculating these health advisory levels, and then there are, in some ways, technical, but frankly, practical considerations that get layered on top of them when they are turned into an enforceable standard,” Moore said.
Those practical considerations include the detection limit for PFAS — the most accurate labs can only detect concentrations down to two parts per trillion, she said.
“Less is obviously better,” she said. “But there isn't a test out there that would allow us to sort of systematically go around the state testing water supplies, and be able to tell folks that they are meeting the recommendations of this health advisory.”
The state may also consider adjusting the method by which the standards are set. Currently, Vermont’s standard combines five types of PFAS linked to human health impacts — any combination of those five should not exceed 20 parts per trillion. The EPA’s advisory, however, takes a chemical-by-chemical approach, singling out PFOA and PFOS and making specific recommendations for each.
The EPA’s guidance marks its first update since 2016. Up until this point, many have criticized the EPA for being slow to issue guidance or investigate the problem.
“I think it's important to keep in mind that New England states … have moved forward pretty aggressively in working to address PFAS in the absence of national leadership over the last six years,” Moore said.
Meanwhile, Jon Groveman, policy and water program director at the Vermont Natural Resources Council, says the organization has been watching the EPA guidance closely. He wants to see the state work from the health advisory to issue stricter standards swiftly.
“We don't see how EPA could set a level for a drinking water standard higher than this if they're saying that this tiny level for at least these PFAS are so harmful that people shouldn't be exposed to them, and certainly shouldn't be drinking them,” he said.
Vermont has stricter standards than most other states, and it’s soon to pilot a PFAS treatment system for garbage leachate — the first project of its kind in the country. Groveman said the state could be doing more, such as regulating the entire PFAS class, rather than only five chemicals.
Montross said concerned citizens can speak with their doctors to assess their risk levels for PFAS. Children under the age of five and women of childbearing age may be more vulnerable to harmful impacts. The state tests bottled water brands for PFAS and lists results on its website. Consumers can also reach out to their water providers to ask about PFAS sampling results.
Roughly $5 billion in federal funding will be distributed to states over the next several years to help address the problem, and Montross said Vermont’s sampling efforts have given officials a leg up.
“We've been out ahead with the sampling, so we do know where that money needs to go,” he said, “and we can help coach and assist those systems in coming to the table to get the money to address it.”
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