NC defers to EPA for GenX health goal. The forever chemical is more toxic than thought.

The N.C. Department of Health and Human Services does not plan to revise its health goal for a “forever chemical” found in southeastern North Carolina despite a federal review that has determined the chemical is toxic at much lower levels than DHHS used when setting its target.

Instead, DHHS will wait until spring 2022 when the Environmental Protection Agency has said it expects to publish a national drinking water advisory level for GenX. The toxicity assessment published Monday and advisory anticipated next spring are both parts of the EPA’s new effort to address per- and polyfluoroalkyl chemicals nationwide.

The EPA’s review found a reference dose, or the estimate of how much a person can ingest over the course of their lifetime without suffering adverse health effects, of .000003 mg/kg/day. That compares with the .0001 mg/kg/day that DHHS used in 2017 to set its health goal of 140 parts per trillion.

If DHHS were to insert the new reference dose into the formula it used in 2017, the health goal would be about 4 parts per trillion.

Levels of GenX measured in the Wilmington-area Cape Fear Public Utility Authority’s drinking water this year have consistently been below 10 parts per trillion, but only occasionally below 4 parts per trillion.

“North Carolina health officials should absolutely review the final toxicity assessment from EPA and look at revising their drinking water guidance value because of this, essentially, much more comprehensive document and consideration of the potential for harm,” said David Andrews, a senior scientist at the Environmental Working Group.

According to the EPA’s new toxicity assessment, the liver is particularly vulnerable to drinking water containing GenX. Animal studies have also shown that GenX has adverse impacts on “kidneys, the immune system, development of offspring and an association with cancer.”

Per the new EPA data, GenX is more toxic even than PFOA and PFOS, a pair of PFAS that companies were forced to phase out due to their toxicity. The EPA did caution that the PFOA and PFOS levels could change after the agency finishes an ongoing review.

Catie Armstrong, a DHHS spokeswoman, said the agency is not updating its drinking water health goal to stay aligned with the EPA’s guidance.

“We anticipate that the current provisional drinking water health goal will likely be replaced by EPA’s national health advisory level for GenX in drinking water when that becomes available,” Armstrong said in a statement.

The EPA’s health advisory will be similar in concept to North Carolina’s drinking water goal, a non-enforceable concentration level below which someone could be expected to drink water for a lifetime without suffering health effects. According to EPA’s PFAS Roadmap, health advisories offer “a margin of protection.”

GenX is found in the lower Cape Fear River Basin due to Chemours’ plant near the Bladen-Cumberland county line, where the company and its predecessor DuPont discharged the chemical for more than 35 years.

In 2017, after the presence of GenX in Wilmington-area drinking water became public knowledge, DHHS set an initial drinking water health goal of 71,000 parts per trillion. The agency quickly reduced that to 140 parts per trillion.

DHHS officials said at the time that the health goal was the level at which a person should be expected to drink water for their whole lives without suffering adverse health effects. The state drinking water goal has ramifications for thousands of residents around and downstream of Chemours’ plant, as well as for the water utilities which serve them.

Levels of GenX have fallen significantly in the Cape Fear River since the chemical was discovered, in large part due to discharge and emission-control measures that were installed due to a consent order signed between Chemours, the N.C. Department of Environmental Quality and Cape Fear River Watch. Water utilities in and around Wilmington have also spent hundreds of millions of dollars upgrading their water treatment technology to capture the evasive chemicals.

Lisa Randall, a Chemours spokeswoman, said the company is reviewing the data EPA used in its review process to see what changed from the 2018 draft assessment to lower the reference dose from the .00008 mg/kg/day in the draft assessment. The new reference dose is nearly 27 times lower, meaning any future drinking water advisories or regulations would likely start at a significantly lower level.

“We are unaware of data that would support the conclusions drawn by the agency,” Randall said in a statement.

“We’re reviewing the information for additional insight into the new review process used by the agency and the new data the agency utilized for the change from its 2018 draft assessment, including the application of revised uncertainty factors to reflect greater uncertainty even though the agency indicates there is additional data since the draft assessment.”

Jamie DeWitt, an East Carolina University environmental toxicologist who serves on North Carolina’s Secretaries’ Science Advisory Board, said she believes that the only safe level of a PFAS is zero. But, DeWitt added, the EPA assessment is “rigorous” and takes recent research into account.

Regarding the new reference dose, DeWitt said, “It’s a defensible value given the information that we have available to us today. There are going to be people who don’t think it’s protective enough and there are going to be people who think it’s too protective.”

Monday’s toxicity assessment is part of a suite of actions on per- and polyfluoroalkyl substances that EPA Administrator Michael Regan announced during a visit to Raleigh last week. EPA officials said their plan is designed to regulate, remediate and research the long-lasting chemicals that are found throughout modern life from stain-repellent carpets to food wrappers to cell phone components.

In a statement, Radhika Fox, EPA’s assistant administrator for water, said, “This science-based final assessment marks a critical step in the process of establishing a national drinking water health advisory for GenX chemicals and provides important information to our partners that can be used to protect communities where these chemicals are found.”

This story was produced with financial support from 1Earth Fund, in partnership with Journalism Funding Partners, as part of an independent journalism fellowship program. The N&O maintains full editorial control of the work.