Water in Raleigh, Durham, Chapel Hill contains PFAS above new EPA health advisory levels
Samples taken in recent years show that unfinished drinking water from dozens of utilities across North Carolina contain concentrations of “forever chemicals” well above the interim health advisory levels set this week by the U.S. Environmental Protection Agency.
The N.C. PFAS Testing Network sampled raw water — water that has not passed through a plant’s treatment process — from every municipal or county water system across the state in 2019 and 2020, with the labs capable of detecting PFOA and PFOS at levels as low as one part per trillion. Scientists concluded that samples from 44 utilities contained PFOS above the EPA’s .02 ppt advisory level, while 38 had PFOA above the new .004 ppt level.
Many of those samples came from utilities in the Triangle, including Raleigh Water and the Orange Water and Sewer Authority. More recent testing by those utilities and others, including Durham’s Department of Water Management, indicates that drinking water that has been treated also frequently contains concentrations of PFOA and PFOS above the health advisory levels.
Water from those utilities did not contain concentrations above the EPA’s former lifetime health advisory level of a combined 70 ppt of PFOA and PFOS.
A lifetime health advisory is meant to provide the amount of a chemical a person can be exposed to for their entire life without it causing adverse health impacts.
PFOA and PFOS are per- and polyfluoroalkyl substances (PFAS) that were used throughout the economy for decades After evidence about the man-made chemicals’ impact on human health began to mount in the 1990s and early 2000s, the EPA worked with manufacturers to largely phase them out.
But the chemicals are long-lasting and move easily in water, meaning they are frequently found in water supplies today.
The EPA’s new limits are so low that it’s impossible for Lee Ferguson, a Duke University environmental analytical chemist who is one of the co-leaders of the testing network’s sampling effort, to say how many samples contain concentrations of PFOA or PFOS that the federal government considers dangerous over a lifetime of exposure.
Ferguson’s lab can find the chemicals at concentrations as low as one part per trillion, but the EPA’s health advisories are .02 ppt for PFOA and .004 ppt for PFOS.
“Essentially anything that can be measured using current technology in water — any detection — is considered to be a risk with respect to health exposure over the long term,” Ferguson said.
PFAS in Triangle drinking water
Some utilities, including several in the Triangle, routinely test for PFAS chemicals in their treated drinking water. Those tests frequently show that the water supplied to customers contains levels that are well above the new EPA recommendations.
For instance, Raleigh Water’s most recent samples, collected in January, show that water from Falls Lake treated at the E.M. Johnson Water Treatment Plant contained 5.1 ppt of PFOS and 3.4 ppt of PFOA. Drinking water from Lake Benson that was treated at Raleigh’s Dempsey E. Benton Water Treatment Plant had 3.3 ppt of PFOS and 2.3 of PFOA.
Edward Buchan a Raleigh Water spokesman, said the agency is reviewing the new health advisories.
“Raleigh Water is in full compliance with all NC drinking water requirements and EPA’s Safe Drinking Water Act, and we will continue to work with our industry partners and regulatory agencies to ensure our drinking water meets all current and future regulations,” Buchan wrote in a statement.
The City of Durham’s Water Management Department acknowledged in a press release Thursday that its drinking water contains PFOA and PFOS above the advisory levels.
The department has sampled its water quarterly since February 2018. Drinking water from the Brown Water Treatment Plant has averaged 4 ppt of PFOA and 6.3 ppt of PFOS over the last four years, while the Williams Water Treatment Plant has averaged 4 ppt of PFOA and 6.4 of PFOS.
Durham officials said they need to conduct more monitoring to determine when PFOA and PFOS levels spike, research treatment options that can remove the chemicals and figure out how to cut down on PFAS as the EPA moves toward an enforceable drinking water standard.
“The lower the level, the lower the risk and as always, public health and the quality of your drinking water is our top priority,” said Durham’s statement.
Orange Water and Sewer Authority, which provides drinking water to Chapel Hill and Carrboro, has been testing for PFAS quarterly since 2018. Those samples routinely contain concentrations of PFOA and PFOS above the advisory levels, including the 19 ppt of PFOA and 15 ppt of PFOS detected in a sample this year.
In an interview, Blake Hodge, an OWASA spokesman, said, “We are certainly going to be evaluating these health advisory levels and evaluating our treatment process, what we can do, what we need to do, what’s the next step. A lot of those discussions of course are still being had, as we’re still in the early days of this.”
Raw water in the Triad and in Southeastern North Carolina also showed levels of PFOA and PFOS above the EPA’s advisory levels.
Additionally, the raw water samples from 2019 showed that untreated water from nine plants in southeastern North Carolina contained levels of GenX above the 10 ppt health advisory level the EPA set this week. Of those utilities, Brunswick County and the Wilmington-area Cape Fear Public Utility Authority have started work on $167 million and $46 million projects, respectively, to remove PFAS from drinking water.
In a video posted Thursday, Greensboro Water Resources Director Mike Borchers explained that health advisory levels are guidelines. Borchers also said that while sampling regularly shows concentrations of PFOA and PFOS above the health advisory levels, the city’s water is “absolutely and emphatically” safe because it meets all regulatory standards
Health effects of forever chemicals
The EPA evaluated more than 400 studies in deciding to drop the health advisory level for PFOA and PFOS from the combined 70 ppt level the agency set in 2016, Radhika Fox, the EPA’s assistant administrator for the office of water, told attendees at a conference in Wilmington this week.
The chemicals have been linked with a wide range of health effects from increased risk for kidney and liver cancer to increased cholesterol to changes in liver enzymes. According to the EPA, the health effect that led to this week’s advisory levels was a decreased immune system response to vaccines in children.
After touring a Wilmington water treatment plant on Wednesday, Fox said that water systems could start testing for PFOA, PFOS and other PFAS compounds to determine if they need additional testing or monitoring. That could help, she said, when EPA proposes its enforceable drinking water standards, something the agency is trying to do by the end of this year.
“If they then are testing for it and then they see it in their water supplies, that’s a great opportunity to start a conversation with their state drinking water utility, their state regulators,” Fox said.
The health advisories will play a role in the level at which EPA proposes the standard later this year, Fox said Wednesday.
“We’re absolutely looking at that,” Fox said, “but that’s not the only input that goes into setting an enforceable standard.”
In a PFAS Action Plan released this month, DEQ pledged to start working in the summer of 2022 toward setting state groundwater standards for certain PFAS compounds. Those include PFOA, PFOS, GenX, PFBS and PFBA.
Additionally, the agency plans to start working toward a surface water standard for PFOA in the fall of 2022 or winter of 2023. And Secretary Elizabeth Biser has said the agency will develop drinking water standards for “priority PFAS.”
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.
This story was originally published June 17, 2022 at 5:58 PM.