PFAS Cholesterol Study Adds to Research on Heart Disease Link

Some PFAS increased levels of “bad” cholesterol, and others increased the “good” type, according to a study that adds to the evidence that the chemicals affect fats in blood and some may contribute to heart disease.

Two older forms of per- and polyfluoroalkyl substances, or PFAS—perfluorooctane sulfonate (PFOS) and perfluorononanoic acid (PFNA)—increased the amounts of “bad” cholesterol in people’s bodies, said Jane Hoppin, a biology professor at North Carolina State University and lead author of the study, which was published Wednesday in the journal Environmental Health Perspectives.

It’s been known that some older PFAS can increase cholesterol, but the potency is significant, she said. High concentrations of PFAS could push people, particularly older individuals, into the “high cholesterol” category that’s known to increase risk of heart disease, the study found.

Two fluoroethers, a little-studied type of PFAS that’s been released by the Chemours Co.‘s chemical plant in Fayetteville, N.C., increased “good” cholesterol, but that doesn’t mean they’re good for the body, Hoppin said. It shows they too affect “lipids,” or fats, in human blood, an outcome that needs further study, she said.

“Anything that alters lipids could have long-term health consequences,” Hoppin said.

Broader Study Continues

The investigation, which involved 326 people in North Carolina ranging in age from 6 to 86, is part of a broader GenX Exposure Study.

Hoppin and other scientists involved in that study are examining the exposure that people living near North Carolina’s Cape Fear River Basin have to GenX chemicals, which have been generated by a manufacturing technology Chemours uses. The scientists also are studying exposure to other forms of PFAS, which Hoppin said come from multiple industrial and other sources.

The original study, which has grown to include more than 1,000 local residents, also will look at health effects, including whether PFAS impact the Covid vaccine’s effectiveness, she said. Some PFAS have made vaccines less effective.

Interestingly, the research team didn’t detect the chemical that prompted the study, hexafluoropropylene oxide dimer acid (HFPO-DA or GenX), in participants’ blood.

The chemical remains only a few days in people’s blood, and the study was launched in 2017, Hoppin said. That means it began after a combination of efforts reduced people’s exposures to GenX, she said.

Those efforts included Chemours dramatically reducing the amount of GenX released into the Cape Fear River and the atmosphere, local residents drinking bottled water or using filters to remove the chemicals, and eventually local water utilities removing PFAS from drinking water.

“It’s good for the community that the levels have come down,” Hoppin said. But the study will continue to examine whether people’s historic exposures to GenX, which reached up to 700 parts per trillion (ppt) in water, had health consequences.

The EPA in June recommended that people consume no more than 10 ppt HFPO-DA and its ammonium salt in drinking water daily over their lifetimes, a recommendation Chemours is fighting in court.

Chemours declined to comment immediately on the study.