LANSING, Mich. (WLNS) — New research from Michigan State University shows that exposure to per- and polyfluoroalkyl substances (PFAS) may weaken the immune system in adults.
The study found that individuals with higher levels of these “forever chemicals” in their blood produced fewer protective antibodies when encountering new viruses.
PFAS are a large class of human-made chemicals used in products such as nonstick cookware, stain-resistant fabrics and firefighting foams. MSU reports that these substances do not easily break down in the environment and can accumulate in the human body over several years.
“Antibodies act like tiny soldiers, helping the body recognize and fight off viruses,” said Courtney Carignan, senior author of the study and an environmental health researcher at Michigan State University.
Courtney Carignan, senior author of the study and an environmental health researcher at Michigan State University./ Michigan State University.
“These results raise important concerns about how long-term exposure to PFAS reduces the body’s ability to respond to infections, even in adulthood,” Carignan said.
The study, conducted by Michigan State University, focused on people previously exposed to the chemicals through contaminated drinking water to measure how effectively the body responds to infection.
According to MSU, one specific compound highlighted in the study, perfluorohexanesulfonic acid, or PFHxS, can persist in the human body for nearly a decade. This persistence makes it a significant marker for measuring long-term exposure.
Researchers found that the reduction in antibody production was most pronounced among men, older adults and people who are overweight. These groups typically have higher levels of PFAS in their bodies.
“Previous studies in adults have produced mixed results, in part because prior exposures and existing immunity can make responses difficult to isolate,” Carignan said.
“The pandemic provided a rare opportunity to observe how the immune system responds to a new virus, allowing us to more clearly detect how PFAS exposure may influence antibody production and helping resolve long-standing uncertainty about its effects in adults. Our findings make clear that PFAS exposure can affect immune response in adults in addition to the known effects in children,” said Carignan.
The health effects described in the study match the experiences of families in Belmont, Michigan, who were affected by contaminated drinking water.
Tobyn McNaughton, a local mother and clean water advocate, discovered the impact of the chemicals after her family was exposed to them. McNaughton contacted Carignan in 2018 to investigate PFAS levels in her family’s water supply.
McNaughton Family./ Michigan State University
“When you find out your family has been exposed, it changes everything — especially how you think about your children’s health,” said McNaughton. “We’re poisoned people. We learned that some of my son’s childhood vaccines weren’t fully effective due to his compromised immune system, and that’s something no parent expects to face.”
Carignan emphasized that reducing chemical levels in the water supply is the primary method for improving health outcomes. Researchers and advocates indicated that continued monitoring and strict regulation will be necessary as the new EPA standards are enacted.
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