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Risk of PFAS Sabotaging Covid Vaccines’ Promise Spurs Study (1)

Dec. 11, 2020, 11:01 AMUpdated: Dec. 11, 2020, 8:23 PM

The FDA’s anticipated approval of the first coronavirus vaccine enables scientists to kick off studies examining whether “forever chemicals” hinder the effectiveness of Covid-19 vaccines.

But studies set to go when vaccines reach their local communities aren’t big enough to shed light on what the Centers for Disease Control and Prevention has already said is an important question facing communities: how exposure to per- and polyfluoroalkyl substances may affect their risk of getting infected by Covid-19.

The ubiquitous and persistent chemicals known as PFAS have made it from factories and products into air, and the bloodstreams of 95% of Americans. Some groups, such as military firefighters and communities near bases or factories, have higher levels than others. Some of the chemicals are already linked to a whole host of problems, including making vaccines less effective and increased risk of cancer.

Now, scientists want to know if higher PFAS levels in people’s bodies leave them less protected from a vaccine—though all emphasized that everyone should still get vaccinated.

That’s the question Rep. Dan Kildee (D-Mich.) is asking. Kildee represents communities where elevated levels of PFAS have been found in drinking water.

Scientists must quickly find out whether these chemicals reduce coronavirus vaccines’ effectiveness, and then decide if PFAS-exposed people need additional interventions to get protected, he told Bloomberg Law.

“By daylighting this issue now, we can highlight something that could make the vaccines more effective for all,” he said. “Someone with higher exposures to PFAS needs to know if they need to take additional steps to protect themselves.”

Vaccines Work in New Ways

PFAS are a huge group of chemicals used in everything from cables and firefighting foam, to cookware and computer chips.

Their ubiquitous uses and the long time that some PFAS stay in the environment and people’s bodies mean 95% of the U.S. population have these chemicals in their blood. Studies already have shown that some PFAS weaken the immune system and make the measles and other vaccines less effective.

Food and Drug Administration advisers on Thursday gave their nonbinding approval of a vaccine Pfizer Inc. and BioNTech SE developed to help people 16 years or older people fend off the coronavirus. And the FDA advisory committee is scheduled on Dec. 17 to review a second coronavirus vaccine that Moderna, Inc. developed for people 18 and older.

Yet the coronavirus vaccines from Pfizer and Moderna work differently from traditional vaccines, and previous studies may not be applicable, said Philippe Grandjean, a Harvard School of Public Health physician and one of the foremost researchers investigating the immune and other health effects of chemicals, including PFAS.

The amount of protection the vaccines provide PFAS-exposed people is important, because a recent study showed people with higher amounts of one PFAS, perfluorobutanoic acid (PFBA), got sicker from Covid-19, said Grandjean, the principal investigator of that research. The study is being critiqued by other scientists. PFBA remains in the lung, which might explain the finding, he said.

“My worry is that we vaccinate people with high PFAS exposures, and the vaccine is not protecting them, but they behave differently,” he said, such as stop wearing masks and having more social interactions.

Kildee Seeking Answers

CDC Director Robert R. Redfield sent Kildee a letter last month that showed federal health agencies are “further ahead than I would have thought” in recognizing the issue, the legislator said. The agencies are already supporting some relevant research—but not enough attention is going to ensuring the vaccine is effective for vulnerable communities, he said.

Kildee, who plans to remain on the House Ways and Means Committee during the next Congress, said he’s prepared to leverage that committee’s authority to push for oversight hearings and special funds to spur additional research.

The CDC, its Agency for Toxic Substances and Disease Registry—which examines the health effects of chemicals—and six scientists described various studies that are underway, or could be done as people get vaccinated, to answer two questions: Do elevated PFAS levels interfere with coronavirus vaccines’ effectiveness, and do people with excessive PFAS get sicker from the coronavirus.

But the researchers admitted the studies aren’t big enough for definitive answers on the vaccine questions.

“We want to get data sooner rather than later” to prevent the disease from spreading, said Linda S. Birnbaum, a National Institute of Environmental Health Sciences researcher who retired last year as director of both that institute and the National Toxicology Program.

Tom Flanagin, a spokesman for the American Chemistry Council, which represents chemical producers, said it was “misleading and inaccurate” not to acknowledge the significant uncertainty about PFAS exposure affecting vaccine effectiveness.

“Our products in use today have been approved through rigorous regulatory review, and in fact are used in many essential medical applications in the fight against Covid-19,” Flanagin and the council said in a statement posted online Friday.

Smaller Studies

Laurel Schaider, a research scientist with the Silent Spring Institute, and Jane Hoppin, an environmental epidemiologist with North Carolina State University, are studying PFAS-exposed communities.

The university is looking at whether a local community exposed to GenX, one type of PFAS, get sicker from Covid-19 and how they would respond to coronavirus vaccines when those become available, Hoppin said.

Schaider, whose group studies chemicals’ health effects, is looking at PFAS-exposed communities in Massachusetts, and hopes to add both coronavirus susceptibility and vaccine effectiveness to that research.

But those studies, with several hundreds of participants, don’t have the thousands of people to get needed answers, both researchers said.

More Powerful Studies

Other, larger studies, including from the CDC, are also looking at whether PFAS affects the severity of Covid-19—but they don’t yet include specific research to look at vaccine effectiveness.

CDC’s HEROES study is examining Covid-19 in health care personnel and first responders, said Rachel Rogers, an environmental health scientist with the Agency for Toxic Substances and Disease Registry. As part of that study, ATSDR will measure participants’ PFAS blood concentrations to help determine any link between the chemicals and Covid-19, she said.

The study doesn’t directly measure the effectiveness of vaccines, but “may shed light on the potential impact of PFAS exposure on vaccine response and potential duration of vaccine protection,” she said.

CDC and ATSDR also are exploring ways to add Covid-19 research into an ongoing study on the health effects of communities with drinking water that’s been contaminated by PFAS, she said. And ATSDR is developing a study to examine PFAS exposure and susceptibility to viral infections, including Covid-19, Rogers said.

Jefferey L. Burgess, a physician and associate dean for research at the University of Arizona, recently received federal funds to study the severity of and immune response to the coronavirus among PFAS-exposed firefighters. He’s talking with potential funders to see whether that study could be expanded to look at vaccine effectiveness.

But major research gaps still remain. A study that Harvard’s Grandjean said could be informative and conducted early would involve firefighters on military bases, and others working on such bases who have been exposed to PFAS. PFAS-containing firefighting foams are a known exposure to the chemicals.

The Defense Department didn’t respond to repeated requests for information on whether it’s planning to conduct such studies.

Urgent Message

Silent Spring and Northeastern University are also recruiting families with children for a PFAS study of one Massachusetts and one New Hampshire community, and looking to add coronavirus susceptibility and vaccine effectiveness to that work, Schaider said.

That type of study is critically needed, because children’s immune systems are just developing after birth, said Harvard’s Grandjean and Birnbaum. Yet just as the immune system is developing, infants get extra doses of PFAS from human milk and from the time spent crawling around carpeted floors, they said.

There’s time to plan for that, because coronavirus vaccine trials with children aren’t underway yet, Birnbaum and Schaider said.

The urgent message, however, is for everyone to get the coronavirus vaccine when they can, every individual interviewed stressed.

“Even an individual with a somewhat weakened antibody response could get some benefit,” Kildee said.

(Updated with American Chemistry Council's statement in 19th and 20th paragraphs.)

To contact the reporter on this story: Pat Rizzuto in Washington at

To contact the editors responsible for this story: Rebecca Baker at; Anna Yukhananov at