A NC State team has tested alligators from Greenfield Lake and striped bass from the Cape Fear River

RALEIGH -- Alligators and striped bass in the Wilmington area have levels of per- and polyfluoroalkyl Substances (PFAS) many times higher than their counterparts elsewhere in the state, a finding that surprised the N.C. State University team conducting the research.

"The data right now, with the levels as high as they are, are causing me to start to really believe that the PFAS are likely harming fish and wildlife around these polluted areas," said Scott Belcher, a N.C. State toxicologist, on Tuesday.

Belcher's team compared alligators from Lake Waccamaw in Columbus County and Greenfield Lake in Wilmington with the latter showing levels of total PFAS more than 10 times higher. They also compared striped bass from the Pamlico Aquaculture Field Laboratory and Lock and Dam No. 1 on the Cape Fear River, with the latter showing levels more than 33 times higher.

Researchers are now, Belcher said, looking at whether the PFAS are affecting the immune systems or liver functions of the animals sampled -- endpoints that have also been identified in humans. Partners in the team's research include Cape Fear River Watch, N.C. Sea Grant and the N.C. PFAST Network.

"We are working right now to analyze the health outcomes that we have analyzed and trying to link that with exposure data," Belcher said.

About 90 percent of the PFAS found in the species is, Belcher said, Perfluorooctanesulfonic acid (PFOS), a PFAS substance found in many substances but perhaps most frequently in firefighting foam.

"GenX is our indicator there's a problem that led us to look carefully, but PFOS is the vast majority of the (PFAS) that we're seeing," he said, adding he expects the PFAS total to rise as the team tweaks its sampling curves to account for higher-than-expected levels.

Samples taken from a pair of alligators sampled in Greenfield Lake showed 419 parts per billion (ppb) and 167 ppb of PFAS, compared to numbers in the mid teens in 14 gators sampled from Lake Waccamaw. Researchers targeted 6-foot alligators, figuring those creatures would be 15 to 20 years old and have largely been in the similar area.

Researchers plan to take additional samples at Greenfield Lake as soon as the average daily temperature reaches 60 degrees -- likely around the end of April. Belcher said they are aiming for 20 to 40 more samples there, as well as some additional samples at Lake Waccamaw and from alligators on Bald Head Island.

'Unique' to the Cape Fear

For striped bass, samples from 63 bass at Lock and Dam No. 1 averaged more than 500 ppb of PFAS, while the Pamilico bass were -- like the Waccamaw gators -- in the mid teens.

"We were actually very surprised at seeing levels this consistently high," Belcher said.

In the Cape Fear, GenX was detected in about 53 percent of striped bass, while Nafion byproduct 2 was found in 78 percent. The chemicals were not detected in the Pamlico population.

"They were unique to the Cape Fear River," Belcher said. Both GenX and Nafion byproduct 2 are linked with Chemours' Fayetteville Works facility near the Bladen-Cumberland county line.

Madi Polera, who will start working on her Ph.D. in Belcher's lab this fall, plans to look at whether the PFAS are impacting the ability of striped bass to naturally reproduce in the river. The Cape Fear's striped bass population is currently hatchery raised and then released into the river.

"Our (fish who swim upriver to spawn) are all in some stage of struggling," Polera said, "so as part of the puzzle of fishery restoration, we just want to be asking the question about if these chemicals could be further impacting their ability to reproduce."

Polera's project will start with the samples already taken of striped bass and could eventually expand to include sturgeon. Other factors potentially impacting fish's ability to reproduce could include water quality, habitat and the locks and dams along the river.

"Realistically, there are probably multiple things that are interacting that continue to make fishery restoration a challenge on the Cape Fear River," Polera said.

Source of contamination?

When another N.C. State team sampled the blood of Wilmington-area residents, Nafion byproduct 2 was among four PFAS chemicals detected in the Wilmington region that were not found in samples taken from Triangle-area women in 2008-9 or Dayton, Ohio, residents between 1992 and 2014.

Belcher was extremely hesitant to say whether the high levels in wildlife could be contributing to human exposure -- particularly because there is a long-time moratorium on catching striped bass in the Cape Fear.

It was also not immediately clear where high levels of PFOS could be coming from, although PFOS and PFOA have been found near the Piedmont Triad International Airport upstream, while the Department of Defense has said PFOS is believed to have been released from Fort Bragg.

"We really don't understand how (PFOS) is mobile within the environment," Belcher said, "and by environment, I mean the ecosystem, as well as the water itself."

Reporter Adam Wagner can be reached at 910-343-2389 or Adam.Wagner@GateHouseMedia.com.