A group of chemicals called PFAS (per- and polyfluoroalkyl substances), colloquially known as “forever chemicals” because of their lengthy degradation time, are nearly inescapable. Commonly used to repel water and reduce the friction on surfaces, they’re found in raingear, lotion, non-stick pans, dental floss, food packaging, surgical gowns, electronics, and the foam used to fight fires. 

Now, a new study shows that people with elevated levels of PFAS in their blood—most often a result of exposure to contaminated drinking water or food—could have more severe cases of COVID-19. Of the 323 COVID-19 patients screened in the study, more than half of those seriously ill with the disease had elevated levels of a particular type of PFAS—known as PFBA—in their blood. 

“These chemicals interfere with the immune system,” says Phil Brown, a university distinguished professor of sociology and health sciences at Northeastern who studies the effects of PFAS on people’s health. “PFAS have been shown to suppress B cells, which are very important for producing antibodies.”

On top of that, effects of PFAS on the immune system have also been associated with an overactive immune system. “Cytokine storm” is one effect of COVID-19 seen in more severe cases. 

Cytokines are the proteins that activate the self-destruct button in infected cells, which is usually a good strategy for protecting healthy cells from infection. But if cytokines flood the body in a “storm,” the immune system mistakenly attacks all cells instead of only those infected with the virus, says Brown, who is also the director of the Social Science Environmental Health Research Institute at Northeastern, as well as co-director of the Institute’s PFAS Project Lab. 

In COVID-19 patients, that rapid cell death can cause a huge loss of tissue, especially in the lungs where the virus accumulates. As the tissue breaks down, the air sacs in the lungs become leaky and fill with fluid, ultimately leading to pneumonia, a major cause of death among COVID-19 patients. 

“It’s like overdosing on your immune system,” says Brown, who intends to incorporate COVID-19 research into his ongoing study about the health effects of high levels of PFAS in drinking water. 

The negative consequences PFAS have on the immune system can also reduce the efficacy of vaccines, Brown explains. Suppressed immune systems are less likely to respond to inoculations.

“Another concern here is that you wouldn’t necessarily know that the vaccine might not work unless you were testing for [PFAS],” he says. Even though the chemicals are widespread—97 percent of Americans have some level of PFAS in their blood—it’s not routinely checked for or considered during vaccination. 

The Centers for Disease Control and Prevention is currently investigating whether heightened levels of PFAS cause more severe cases of COVID-19 or have any effect on the vaccine. “In the past, when we saw that children had antibody levels that were below the level of protection, we just gave the child another booster vaccination,” said Phillippe Grandjean, lead author of the study on PFAS and COVID, in an interview with Chemistry Magazine. 

“I would think that this option needs to be considered also for the [coronavirus] vaccines, but I would first like to see data on corona antibody levels in people with different levels of PFAS exposure,” Grandjean continued.  

Of all the PFAS, the chemical known as PFBA—found in carpets, stain-resistant clothing, eye shadow, and bike lubricant, to name only a few products—is considered by some to be one of the least harmful because it circulates in the blood for less time than other PFAS. But it tends to congregate in the lungs, which is why researchers believe it has such adverse effects on COVID-19 patients. Indeed, many chemicals that leave the body even sooner, such as BPA, have many documented health effects, so that short duration is not necessarily related to less hazard, Brown says.

The consequences of PFAS extend far beyond just COVID-19. The chemicals are also associated with liver malfunction, preterm births, hypertension, thyroid disease, and a variety of cancers including prostate, pancreatic, and ovarian cancer, Brown says. 

“Most of the uses of PFAS aren’t essential,” he says. “We want all these products to slip and slide easier. Teflon pans or dental floss, for example. But we’ve been cooking with cast iron pans and using dental floss that doesn’t have PFAS in it for decades, and they’ve worked just fine. We need to get back to that.” 

For media inquiries, please contact Jessica Hair at j.hair@northeastern.edu or 617-373-5718.