Nearly every American has been exposed at some point to a class of compounds known as perfluoroalkyl and polyfluoroalkyl substances, or PFAS for short. These substances, sometimes referred to as “forever chemicals” because they persist in many environments — including the human body — are present in a huge array of consumer products, from food packaging to stain-resistant couches; are in firefighting foam and used in many manufacturing processes; and have contaminated the drinking water sources of millions of Americans in more than 2,800 U.S. communities.
Although researchers have known about the impact of these chemicals for years, there has been little guidance available for clinicians. A new report from the National Academies of Sciences, Engineering, and Medicine (NASEM) aims to change that.
For two years, we were part of a committee of 15 experts in public health, epidemiology, primary care, occupational and environmental medicine, toxicology, laboratory science, and other disciplines reviewing information on the health effects of PFAS exposure, as well as about testing and treatment. We spoke with clinicians and researchers, engaged with community advocates, and heard from many members of the public to formulate a new approach for addressing this important public health concern.
Our recommendations represent a shift in the way clinicians should approach this ubiquitous environmental health concern, advising for the first time that testing be made available to many more people. We hope the report catalyzes better, timelier, and more individualized care.
The NASEM report confirms many concerns about the effects of PFAS exposure on health. Exposure to these chemicals increases the risk of kidney cancer in adults, decreased antibody responses to infection or vaccination in children and adults, decreased fetal growth, and dyslipidemia in children and adults — specifically increases in cholesterol, a risk factor for heart attacks and strokes. The committee also found suggestive evidence that PFAS exposure increases the risk of thyroid disease in adults, pregnancy-induced high blood pressure, breast and testicular cancers in adults, ulcerative colitis in adults, and changes in liver enzymes in children and adults that may indicate liver problems.
It is understandable that people would turn to their health care providers for answers about what they should do as a result of their PFAS exposure. But the current clinical guidance from the Agency for Toxic Substances and Disease Registry does not provide specific advice on when to test for PFAS and what clinical follow-up should be done.
The NASEM report recommends offering PFAS blood testing to anyone likely to have a history of elevated exposure to these chemicals. That means the millions of people living in communities with confirmed drinking water contamination, as well as those with occupational exposure like firefighters, and those who live near possible drinking water contamination: communities near commercial airports, military bases, wastewater treatment plants, farms where sewage sludge may have been used, or landfills or incinerators that have received waste containing PFAS.
Offering PFAS blood testing to individuals likely to have a history of elevated exposure to these substances is not the current the standard of care. The main reason for these new recommendations is that our understanding of the relationship between PFAS blood levels and health risks has advanced enough for testing to be useful to patients likely to have had a significant exposure.
The NASEM report recommends that clinicians interpret blood test results using serum or plasma concentrations of the sum of seven different PFAS, which could all come from the same test panel. A serum or plasma concentration of less than 2 nanograms of PFAS per milliliter (ng/mL) is not linked to adverse health effects, and so no special care is recommended. A concentration between 2 and 20 ng/mL increases the risk for health problems, and clinicians should inform patients about the need for follow-up testing for dyslipidemia, high blood pressure during pregnancy, and screening for breast cancer. Although everyone, regardless of their PFAS blood level, could benefit from reducing their exposure to these chemicals, the report does not focus on this for those with lower PFAS blood levels.
Individuals with PFAS levels above 20 ng/mL can face a higher risk of adverse effects. Clinicians should help them identify how they’ve been exposed and prioritize screening for dyslipidemia. Tests for thyroid function and assessments for signs and symptoms of cancers, including kidney, breast, and testicular cancer, and for ulcerative colitis should be considered at all wellness visits.
Extending PFAS testing to a larger population than is currently being tested will be challenging. Although the committee was not asked to address the challenges of testing, any clinician who has ordered a PFAS test knows that only a limited number of labs currently perform this type of testing, and the tests are often not covered by insurance, possibly costing individuals hundreds of dollars.
Many people living in communities with potentially high exposure to PFAS have been diverted from testing by their health care providers and told that testing is not possible or useful, which would be congruent with existing guidance from the Agency for Toxic Substances and Disease Registry. But the NASEM committee believes that testing provides important information, and individuals can use it to understand their own risk and discuss with their clinician the appropriate next steps.
The report also offers clinicians advice for more sensitive conversations, like how to discuss the risk of passing PFAS to infants through breast milk or formula. It recommends that the Centers for Disease Control and Prevention support clinicians by creating educational materials on reducing exposure, health impacts, the limitations of testing, and the pros and cons of testing that they can share with patients.
We believe that a key take-home message in the new report is the importance of personalizing both PFAS exposure assessment and care for those with elevated levels of these chemicals. Given how much more needs to be learned about how to decrease PFAS-associated risks, it’s clear that testing, the plan for follow-up care, and sensitive issues like breastfeeding should all be based on patients’ values and preferences.
Ned Calonge is an associate professor of family medicine at the Colorado School of Medicine, University of Colorado, Denver, and an associate professor of epidemiology at the Colorado School of Public Health. Jane Hoppin is a professor of biological sciences and director of the Center for Human Health and the Environment at North Carolina State University, and leads an NIH-funded study of PFAS exposures in the Cape Fear River basin. Alex R. Kemper is the division chief of primary care pediatrics at Nationwide Children’s Hospital and professor of pediatrics at the Ohio State University College of Medicine.