Monday, February 26, 2024

GenX got attention. Progress on 1,4-Dioxane has lagged behind

The Cape Fear River as seen from Lower Cape Fear Water and Sewer Authority’s Kings Bluff pump station. (Port City Daily photo/Johanna Ferebee)

SOUTHEASTERN, N.C. — 1,4-Dioxane’s federal drinking water cancer risk assessment level was first established in 2013. This assessment, described by the engineer who has chased down these emerging contaminants for years, is the “gold standard of understanding toxicity.”

Though research teams have recorded alarming levels of the likely human carcinogen for years, its presence in North Carolina drinking water hasn’t (yet) triggered any lawsuits or caused as much of a stir as GenX, a chemical with no federal cancer risk assessment level.

Related: New research revealed higher past levels of PFAS. What does that mean for current – and future – water quality?

GenX got a Department of Health and Human Services (DHHS) preliminary risk assessment health goal the day the StarNews published its June 2017 exposé, “Toxin taints CFPUA drinking water,” complete with unignorable alliteration (technically, GenX is a “toxicant,” a scientific distinction likely lost on the hundreds of thousands of people impacted by the information that followed in the days after the article).

A DHHS risk assessment goal is toothless, but still, it’s a benchmark aimed to help the public understand at what levels drinking water should be considered safe.

In New Hanover County, lifetime plant upgrades at Cape Fear Public Utility Authority (CFPUA) will cost $215 million, necessitating a $5 bi-monthly rate increase for the average customer (local utilities hope upgrade costs will be recouped in the form of a federal class-action lawsuit filed against Chemours). After improvements, CFPUA’s removal rate for GenX will be close to total; 1,4-Dioxane removal rates will not change, as CFPUA is one of the few utilities in the state already equipped to filter out the compound through its biofilm, which has accumulated on existing filters set to remain in place after the upgrade.

Removal rates for PFAS, including GenX will be above 95%. For 1,4-Dioxane? 67%.

Asked if CFPUA was satisfied with a 67% 1,4-Dioxane removal rate, or alternatively, if it would be satisfied with a 67% PFAS removal rate, its spokesperson said:

“The Sweeney Water Treatment Plant is among the few in the state that can effectively reduce levels of 1,4-dioxane. Concentrations in finished water are a factor of concentrations in water we source from the Cape Fear River: more in the river typically results in more in the finished water. Of course we want to have as little as possible. We’d like to have no 1,4-dioxane just like we’d like to have no PFAS. In the end, though, we’re at the mercy of what happens upriver. Source control is always going to be the most effective way of dealing with this.”

GenX v. 1,4

Comparing the two likely cancer-causing compounds, not necessarily on their assumed human toxicity risks, but rather on their respective social impact timelines, reveals how public disclosure, followed by public pressure, can force (or at least speed up) progress.

“What puzzled me about GenX is when it comes to the other compounds, like 1,4-Dioxane or bromide, the [Department of Environmental Quality] kind of hides behind, ‘Well they’re unregulated, we don’t really know what to do.’” Detlef Knappe, N.C. State University scientist, said in an April interview with Port City Daily.

Knappe has spent the last several years of his career closely monitoring emerging contaminants including 1,4-Dioxane, bromide, and per- and poly-fluoroalkyl substances (PFAS). As a civil engineer, the social response that followed the GenX story surprised him. He had been alerting and cooperating with Department of Environmental Quality (DEQ) higher-ups on emerging contaminants for years but, until 2017, he was largely ignored.

“But with GenX, it was even less well characterized in terms of toxicity and they were able to do something. That part is still a little bit of a puzzle to me. But at the same time, they’re using that argument to kind of stall the progress on 1,4-Dioxane and bromide,” Knappe said. “Why is it that GenX was so explosive in a way, and you know, some of the other things I’ve been pushing for a long time like 1,4-Dioxane or bromide, it’s kind of — nothing happens.”

Little was scientifically known about GenX when its presence in the Cape Fear River was publicly disclosed. In November 2016, Knappe shared the publication with the DEQ. In the spring of 2017, then StarNews freelancer and current CFPUA spokesperson Vaughn Hagerty found the article online, and ultimately based his reporting on it.

“Maybe that’s the difference,” Knappe said. “If it’s completely unknown, you wonder, ‘How bad is it really?’ That was really a lesson learned for me. I think I had the order reversed.”

Disclosure, health advisory

CFPUA employees co-authored the study, published November 10, 2016. They were made aware of its full findings in May.

The only known person who got fired (but later, was “allowed to resign”) in the whole GenX saga, Mike McGill, was the individual who says he asked to inform the public earlier on, before the utility was approached by Hagerty (in a strange twist of fate, Hagerty now occupies McGill’s former role as CFPUA’s Chief Communications Officer).

McGill was scheduled to present a public communication strategy on GenX at a meeting in April; instead, he said Executive Director Jim Flechtner fired him the morning of, citing “philosophical differences” over public communications (by June, CFPUA was back working with McGill, hiring him on mulitple occasions as a contractor under his newly-formed communications firm for specific assignments).

On June 7, 2017, it’s front-page news. The same day, DHHS sets GenX’s preliminary risk assessment goal at 71,000 parts per trillion (ppt).

Six days later: Flechtner wrote an email to all CFPUA staffers, applauding the utility’s transparency standards. Two days after that: CFPUA’s Chair called for an internal investigation into the utility’s communication and transparency policies. The lead investigator (who formerly worked for Dupont) declined to interview McGill in the review. A week later, on June 22, 2017, CFPUA shared its findings, concluding: “Based upon information and facts available to CFPUA at the time, staff moved the issue appropriately through the CFPUA chain of command.”

By July, PFAS concentrations dropped eightfold. The Governor showed up. DEQ’s Director showed up. Legislators pressured the DEQ to regulate Chemours. DHHS drastically lowered the GenX health goal to 140 ppt.

What changed? Public disclosure. (As in, above-the-fold disclosure, not, publishing a scientific paper and alerting regulators, disclosure).

By May 2018, Cape Fear River Watch had filed a lawsuit against the DEQ, forcing the agency’s hand to enforce the Clean Water Act (this lawsuit led to the much-criticized settlement consent order, with its now-infamous 2018 Thanksgiving-eve delivery).

“It’s as if the public put a gun to their head about GenX,” Dr. Larry Cahoon, a UNCW biological oceanographer and limnologist, said in an April Port City Daily interview. 

“It was an easy word. It was a four-letter word. And it hit suddenly. And it hit in a big way. So it made the right kind of splash.”


Meanwhile, this month, it took an August 1,4-Dioxane plume spiking the community of Pittsboro’s drinking water, and a striking North Carolina Health News headline, for DEQ to name a previously protected Greensboro discharger, Shamrock Environmental. In 2016, the City of Greensboro denied a freedom of information request from previous North Carolina Health News reporter, Catherine Clabby.

In early March, Port City Daily asked the DEQ for a list of potential sources of 1,4-Dioxane being monitored, and also an explanation on why it is difficult to name sources, if DEQ has already been in possession of extensive monitoring data. DEQ did not respond to repeated requests to respond in late March and April. In August, Port City Daily again asked the same questions, in addition to a new request to provide a narrative of DEQ’s 1,4-Dioxane monitoring progress. A DEQ spokesperson provided the monitoring narrative but did not respond to the remaining questions.

Through Knappe and his research partners, DEQ has known about 1,4-Dioxane in state drinking water since at least 2013. The team showed 1,4-Dioxane levels in the Haw River near Reidsville as high as 1,030 ppb in 2015, or over 2,900 times the federal drinking water cancer risk assessment level (this represents the reasonable likelihood for one person out of one million to receive a cancer diagnosis after a lifetime of drinking water with 1,4-Dioxane above .35 ppb). No federal surface water standard has yet been determined, however, most conventional water treatment systems cannot remove 1,4-Dioxane.

In December 2013, CFPUA saw the highest measurement of 1,4-Dioxane it’s ever recorded as part of federally-required Unregulated Contaminant Monitoring Rule testing. At 4.68 ppb testing in finished drinking water, the reading was 13 times higher than the federally-recommended level. CFPUA listed the measurement in its annual 2014 Water Quality Report but did not further explain it within. Port City Daily cannot locate any press release, letter, or other public messaging that described the measurement.

In 2014, three 1,4-Dioxane samples varied, at 0.07, 0.38, and 0.52 ppb, according to figures provided by Hagerty. In 2015, Knappe’s team measured the contaminant in CFPUA finished drinking as high as 2.11 ppb in February, or six times the federal recommendation. Removal rates at CFPUA in 2015 fluctuated between 24% and 77%, according to Knappe’s research.

CFPUA began voluntary testing for 1,4-Dioxane in 2017, according to Hagerty. The utility measured the likely carcinogen once in 2017 (0.18 ppb in finished water) and twice in 2018 (0.23 and 0.32 ppb in finished water).

Starting January of this year, CFPUA began testing monthly for the contaminant. This summer, when levels of 1,4-Dioxane spiked, CFPUA communicated clearly and openly about its measurements.

It’s clear CFPUA’s public messaging of emerging contaminants has shifted in recent years. Instead of answering several questions about CFPUA’s dissemination of this information, Hagerty (the utility’s spokesperson) provided the following statements:

I think it’s fair to say the ongoing attention on what started as “the GenX story” certainly played a role in the increased focus on unregulated contaminants in drinking water.

It’s not just CFPUA. I think increased focus on emerging contaminants, while not necessarily sparked by local media coverage of Chemours’ discharges, is evident at many public water systems and among state and federal regulators, politicians at all levels of government, and people in general.

From our standpoint, CFPUA continues to publish results of our monitoring for 1,4-dioxane and PFAS on our website and provide detailed, timely updates on important developments. Regarding PFAS, we’ve taken interim steps to reduce PFAS levels in drinking water treated at Sweeney Water Treatment Plant and are moving forward to add new deep-bed GAC filters there that will be very effective at reducing PFAS. And we’ve made crystal clear our insistence that Chemours and DuPont, not our customers, should pay to address the damages caused by their decades of PFAS releases that have affected Southeastern North Carolina’s surface and groundwater, land, and air – and not just in the few miles around their chemical manufacturing facilities in Bladen County. We’ve done all of these things very publicly.

Too many boogeymen?

GenX is proprietary. When it showed up in CFPUA drinking water, there was only one boogeyman: Chemours.

“Bang. it’s an easy detective job,” Dr. Larry Cahoon said.

But with 1,4-Dioxane, there are many boogeymen, often industrial companies that discharge into surface waters without the contaminant listed on their National Pollutant Discharge Elimination System permit.

According to Knappe, “Nobody’s adding it in on purpose. It’s just the process of making surfactant.”

Cahoon is outspoken. He’s tenured, he jokes. In May, Cahoon’s work, “Analytical Environmental Chemistry Uncovers Multiple System Failures” was published in the book “Evaluating Water Quality to Prevent Future Disasters.”

Reached this week, Cahoon said his understanding of the system’s failures is more well-developed. “The depth of the failure is deeper than what I knew about at that time,” he said.

He sees the issue with 1,4-Dioxane and other emerging contaminants as not necessarily a resource limitation on the regulator’s behalf, but rather, a “reluctance to enforce.”

“GenX forced them to do something. [1,4-]Dioxane just hasn’t risen to that level,” he said.

[Editor’s note: This article has been updated to clarify when and how former Star News freelancer Vaughn Hagerty learned of Detlef Knappe’s work on GenX; an earlier editorial change incorrectly suggested Detlef had shared his work with Hagerty in late 2016.]

Send tips and comments to Johanna Ferebee at

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