By Will Atwater
Against the backdrop of mounting evidence that links per- and polyfluoroalkyl substances (PFAS) to negative impacts on human health, the National Academies of Sciences, Engineering and Medicine (NASEM) released a study that calls for testing the blood of people with extended exposure to the man-made chemicals. The report focuses on people who have prolonged PFAS exposure, resulting from living near a contamination source or because of occupational exposure.
Since the 1940s, PFAS compounds have been used in the manufacturing of oil and water-resistant products, as well as products that resist heat and reduce friction. There are more than 12,000 different PFAS compounds that are used in products such as non-stick cookware, cleaning products, water-resistant clothing, firefighting foam and protective gear, to name a few.
According to research, an estimated 2,854 locations in the U.S. — in all 50 states and two territories — have documented some PFAS contamination, but not all of this contamination exceeds the level in health advisories. People are primarily exposed to PFAS by drinking contaminated water or eating contaminated food. The report focuses on PFAS that are currently monitored by CDC: MeFOSAA, PFHxS, PFOA, PFDA, PFUnDA, PFOS, and PFNA, according to the report.
The team tasked with producing the study comprised experts from a range of disciplines.
The study brought together a multitude of people with specialized knowledge on topics including ethics, toxicology, and occupational medicine, laboratory and laboratorians, epidemiologists who specifically study PFAS, and clinicians, pediatricians and other medical professionals, according to Bruce Calonge, committee chair and associate professor of epidemiology at the Colorado School of Public Health.
What doctors need to know
The report contains contamination threshold guidelines for how clinicians should treat patients based on their exposure levels. A total of seven PFAS should be considered in the people who have been exposed.
Patients whose blood tests show a PFAS blood concentration below 2 nanograms per milliliter (ng/mL) are not expected to have adverse health effects.
Patients with test results between 2 and 20 ng/mL may face the potential for adverse effects, especially in sensitive populations (such as pregnant individuals). Clinicians are being advised to encourage reduction of PFAS exposure for these people. Clinicians should also prioritize screening for cholesterol and triglyceride imbalances known collectively as dyslipidemia, pregnancy-induced high blood pressure, and breast cancer, based on age and other risk factors.
Patients with test results above 20 ng/mL may face a higher risk of adverse effects, so clinicians should encourage exposure reduction and prioritize screening for dyslipidemia in accordance with guidance for patients with increased risk. In addition to the care recommended for patients who test between 2 and 20 ng/mL, clinicians should also conduct thyroid function testing and assess for signs of kidney and testicular cancers and for ulcerative colitis at all wellness visits.
The report recommends practitioners begin with a conversation on how a patient might be exposed to PFAS, and which exposures they are interested in reducing — including questions about occupational exposures.
People with elevated PFAS in their drinking water should also be advised to filter their water. The report points to a database created by the National Sanitation Foundation International (NSF) to help exposed people locate water filters that can reduce PFAS.
Links between PFAS and adverse health effects
The authors of the reports reviewed research on the health impacts associated with PFAS across many levels of exposure and concluded that there was enough evidence of a link between PFAS exposure and weaker antibody responses in adults and children, along with elevated cholesterol levels. They also noted the evidence points to decreased infant and fetal growth and kidney cancer in adults.
Additionally, authors found evidence of “weaker links” between PFAS exposure and health issues such liver disease, pregnancy-related hypertension, inflammatory bowel disease, thyroid problems and certain cancers.
The study found insufficient links to other health conditions, “such as cardiovascular outcomes other than high cholesterol or developmental outcomes other than small reductions in birth weight,” among others.
What are PFAS?
Per- and polyfluoroalkyl substances (PFAS) are a group of man-made chemicals that includes PFOA, PFOS, GenX, and an estimated 12,000 types of PFAS, none of which are federally regulated. PFAS have been manufactured and used by industries worldwide since the 1940s, used in everything from Teflon pans to raincoats to dental floss. They are also used in firefighting foams.
The two most extensively produced and studied, PFOA and PFOS, have been phased out in the U.S., but they don’t break down easily and can accumulate in the environment and in the human body. There is evidence that exposure to PFAS can lead to adverse human health effects.
Emily Donovan, co-founder of Clean Cape Fear, a Wilmington-based community action group that works on water quality issues, said she has mixed feelings about the NASEM study. Donovan is in an ongoing battle to force Chemours, a chemical company cited for dumping PFAS chemicals into the Cape Fear River, to take full responsibility for removing contaminants from the river and from communities that have contaminated wells as a result of their actions.
“This is the first time NASEM has addressed PFAS exposures with clinicians and a huge gap has been filled,” Donovan said. “Now, North Carolinians can more easily request blood testing and screening procedures related to their PFAS exposures–something communities in the Cape Fear River basin have lacked for years.”
She argued there’s still more work needed to address health disparities for people who are exposed.
“It’s important to note, this guidance is currently addressing legacy PFAS–chemicals no longer in commercial use–because newer PFAS from industrial polluters like Chemours were not included in the original scope of work by NASEM,” Donovan said. “While this guidance is extremely helpful, it does not cover the full scope of PFAS contamination continuing to occur in the lower Cape Fear region.”
Obstacles to overcome
One glaring issue that falls outside the study’s parameters is how will the costs associated with patient blood collection and analysis be covered and where will doctors find the time to add the procedure to their lists of daily tasks.
That issue was raised by L. Kyle Horton, an internal medicine physician and a member of Clean Cape Fear, in a letter signed by more than 60 doctors and sent to the NASEM committee.
“In the complicated arena of modern healthcare delivery, clinicians often have very little time for patient visits, ” she said. ”We are subject to significant limitations as far as insurance coverage and the tremendous burdens on our patients of their out-of-pocket costs.”
N.C. State epidemiologist Jane Hoppin, who was a member of the research team that produced the study, said she understands that there are unanswered questions that need to be addressed in implementing the studies recommendations. Nonetheless, she said the study represents an important step.
“I think probably one of the biggest pieces of this report will be for impacted communities and impacted individuals, so they can go to their doctor and say, ‘you know, here’s my PFAS level, I want to talk to you about some of the health outcomes and what should follow,’” Hoppin said.
“Fundamentally, everybody wants to know, ‘Well, what’s in my body? What does it mean now that it’s in my body? What kinds of health effects could I be at risk for?’ So, I think that’s a major contribution of the work at this point.”
Asheville Firefighters Association president Scott Mullens and many of his colleagues around the country are sounding the alarm about the health risks they face every time they put on their turnout gear because it was manufactured with PFAS chemicals and some firefighting foams still contain PFAS. For Mullens, the NASEM recommendations represent an opportunity to save lives.
“It’s all about prevention and early detection … We’ve seen the data and we know about the concentration of PFAS in turnout gear and how high it is,” Mullens said. “It is cancer-causing, so [the NASEM study] is great news for us. Hopefully, we can [detect] PFAS and give people the help that they need, so cancer doesn’t develop.”