Revised health advisories are a precursor to federal regulation.

Toxic PFAS chemicals have been detected at dozens of groundwater sites across Michigan. Photo © J. Carl Ganter/Circle of Blue

By Brett Walton, Circle of Blue – June 22, 2022

  • The EPA issued new or updated health advisories for four PFAS chemicals: PFOA, PFOS, GenX, and PFBS.
  • Health advisories are not enforceable.
  • The science behind the health advisories will inform federal drinking water standards that will be published later this year.

The U.S. Environmental Protection Agency’s new warnings about the danger of certain PFAS chemicals to human health are a stepping stone toward the agency’s development of national drinking water standards later this year. The warnings also test the limits of laboratory observation.

On June 15, the agency substantially lowered existing health advisories for two of the so-called “forever” chemicals, PFOA and PFOS. The agency also posted first-ever advisories for two additional chemicals, GenX and PFBS.

The new interim advisory levels for PFOA and PFOS are almost inconceivably small. So small, in fact, that laboratory methods cannot detect the chemicals in drinking water at these levels: 0.004 parts per trillion for PFOA and 0.02 parts per trillion for PFOS. The previous advisory level, set in 2016, was 70 parts per trillion combined — more than 10,000 times higher than the new level for PFOA.

“It’s unclear what to do,” said Alan Roberson, executive director of the Association of State Drinking Water Administrators, a group that represents state regulators. Roberson said a health advisory set below the detection level has never happened before.

For members of the general public who are attuned to drinking water contaminants, the EPA announcement is raising concerns, according to John Lovie, president of the Whidbey Island Water Systems Association. Located in Washington state, the association counts about 100 water systems as members, which range in size from several thousand customers to just three or four. The town of Coupeville, one of the largest in the association, is dealing with PFAS chemicals in its water.

Lovie said that people on the island have already started to ask water systems what they are planning to do about the health advisories.

“The short answer is: not very much at the moment,” Lovie said.

Not very much because of the nature of the tool that the EPA is using. Unlike federal drinking water standards, health advisories are not enforceable. Water utilities are not punished if they exceed the limits. The advisories instead are meant as guidance for utilities, notifying them of chemical concentrations at which health damage can occur.

The EPA’s 2016 revision of the PFOA and PFOS health advisories helped to lift the class of nonstick, water-repelling chemicals into the national spotlight. Found in cookware, clothes, carpets, firefighting foams, and burger wrappers, PFAS chemicals number in the thousands. They have been linked to a cluster of undesirable health problems: high cholesterol, kidney cancer, low birth weight, and hampered immune systems.

In developing the new advisory levels, the EPA considered recent scientific findings that suggest health damage occurs at minuscule concentrations. The revised health advisories for PFOA and PFOS are due in large part because the chemicals inhibit vaccine response in children. The advisories are based on a lifetime of tap water consumption.

Two other PFAS chemicals received their first health advisories. The advisory level for GenX (10 parts per trillion) was based on liver damage. The advisory level for PFBS (2,000 parts per trillion), on thyroid effects.

Lovie is concerned that drinking water is being “singled out” in the regulatory world because measuring PFAS in water is easier compared to measuring exposure from other sources of PFAS, like clothing, food packaging, or dental floss.

“It’s thrown a lot of pressure on water systems to do something,” Lovie said. “It seems a bit of a mess.”

Health advisories are the EPA’s first step. The official name for an enforceable federal drinking water standard is a maximum contaminant level, or MCL. The EPA intends to publish draft MCLs for PFOA and PFOS by the end of 2022 and finalize the rules next year.

The lack of federal rules has not stopped states from acting. According to the Association of State Drinking Water Administrators, 11 states have instituted their own health advisories, MCLs, or notification levels. These rules are a mixed bag of mandates and guidance, covering nine PFAS chemicals.

Roberson said that many states are waiting for the federal MCL before taking any additional action.

New Hampshire set its own standards in 2019. Jim Martin, a spokesperson for the New Hampshire Department of Environmental Services, said the state will be engaging with the EPA as the MCL process unfolds.

That process has a second layer. At the same time as the MCL, the EPA will publish a maximum contaminant level goal, or MCLG. This is the level below which no health problems are expected for people who drink tap water over a lifetime.

Because the MCL incorporates economic factors like the cost of compliance, it will undoubtedly be higher than the MCLG. According to an EPA spokesperson, the MCLG will be based on the same science that the agency consulted when developing the health advisories.

For Lovie, the likely divergence between a regulatory standard in parts per trillion and a health advisory in parts per quadrillion means that the EPA and utilities will confront a public communications challenge. They will need to explain why the federal standard is higher than the level which provides the most health protection.

“Hopefully they’re going to come up with some further information on how to rationalize an MCL that’s going to be probably 1,000 times higher at least than the lifetime health advisories that they put out there,” Lovie said. “That’s a hard circle to square.”