"What we observed is in these sunfish, there's very high levels of PFAS in many of them," co-author of the study Erin Baker said. "So you could get almost a year's worth of bad water consumption in one fish."
It's unclear how widespread the contamination is among other fish species. Richard Chavis, who caught a catfish and bream at Jordan Lake on Tuesday, left the bream out after the warning. Bream is a species of freshwater fish that usually includes sunfish and bluegill.
"I don't want to catch them no more," Chavis said.
The study was a collaboration between the University of North Carolina at Chapel Hill and NC State University and had enough information at the time to know there was a reason for concern, according to the first author of the study, Anna K. Boatman.
"I think we have enough information to know that there might be reason to be concerned if you're someone who fishes in Jordan Lake and consumes the fish that you catch," Boatman said. "But more testing would be needed to really say for sure."
PFAS are a group of man-made chemicals found in a host of industrial and personal products, such as fire extinguishing foam and food packaging.
"They're considered forever chemicals, meaning once they're in an organism or in a place, they don't really break down on their own and they tend to stick in your body for some of them days, but some of them up to years," Boatman said.
That's one of the reasons why researchers are warning people to be careful with what they consume.
"If they consume the fish, your body will eventually get rid of it," Baker said. "It's almost like mercury ... so they should just be really careful about any other fish consumption."
Researchers said there are ongoing efforts to address the man-made chemicals, including in the water.
"I know certain water suppliers are using filtration systems to remove the PFAS," Baker said. "The biggest worry is right now getting it out of like lakes and ponds because we can filter it out of our drinking water. But getting it out of natural resources is a lot more difficult."