Illuminating the Health Effects of ‘Forever Chemicals’
SPHHS researchers are studying the myriad ways PFAS chemicals affect human health—and pursuing mitigation strategies
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What chemicals are found in products as varied as nonstick pans, contact lenses, cosmetics, raincoats, firefighting foam, food packaging, and fertilizing sludge?
PFAS, or per- and polyfluoroalkyl substances, are a group of around 15,000 man-made chemicals used in a wide variety of applications due to their unique properties that repel both oil and water and resist stains. Nearly unavoidable, as they frequently find their way into food and drinking water supplies, they are commonly known as “forever chemicals" because many have no known environmental half-life and accumulate over time. Exposure to PFAS chemicals has been linked to a variety of cancers, liver and heart damage, and developmental defects.
“As an epidemiologist, it’s very challenging to study the effects of PFAS chemicals in humans because they’re so ubiquitous and, most of the time, people are unaware of their exposure,” says UMass Amherst Professor of Epidemiology Katherine Reeves.
While some PFAS chemicals—notably, PFOA and PFOS—have been phased out due to safety concerns, they’re being replaced by newer chemicals with similar structures, whose effects are little studied. “There’s a big concern that they will behave in a similar way to the legacy PFAS chemicals we know cause harm,” says Reeves.
While much is still unknown about the health effects of PFAS chemicals, it’s clear that their toxicity is “broad and complex,” says Meichen Wang, assistant professor of environmental health sciences at UMass. She notes that PFAS have been observed to cross the blood-brain barrier, pass into the placenta during pregnancy, and make their way into breast milk. Nationwide monitoring by the Centers for Disease Control and Prevention has found PFAS in around 99 percent of blood serum samples.
“We’re just barely scratching the surface of the health effects of these chemicals,” adds Alicia Timme-Laragy, UMass professor of environmental health sciences. “From immunosuppression and diminished vaccine responses to causing different types of cancer and developmental effects, they appear to get everywhere in the body and have so many health effects.”
Despite these concerns, Timme-Laragy notes that PFAS chemicals’ unique and broadly useful properties are likely to “keep them around for some time.” Thus, researchers in UMass Amherst’s School of Public Health and Health Sciences and across the university are working to better understand the effects of PFAS on human health and explore ways to mitigate damage, with potential implications for regulation and health care.
'Broad and Complex' Health Effects
With many open questions about how PFAS chemicals affect body systems, UMass researchers are working to elucidate the mechanisms by which these chemicals appear to be linked to various health conditions.
Reeves is an epidemiologist whose work focuses on modifiable risk factors in order to reduce morbidity and mortality. With funding from the National Institute of Environmental Health Sciences (NIEHS), she is studying the link between PFAS exposure and breast cancer.
“There are different things that could be at play,” says Reeves. “PFAS chemicals may influence the development of obesity, which is a known risk factor for breast cancer after menopause. Another possible pathway is the presence of PFAS in breast milk. There is evidence in mice that mammary tissue, and especially the ducts responsible for producing milk, are affected by PFAS.”
For this research, Reeves is tapping into the Susan G. Komen Tissue Bank, a unique resource providing access to breast biopsies from thousands of healthy women, along with blood samples, mammograms, and information on a number of factors influencing breast cancer risk. Reeves is studying whether PFAS levels in blood are associated with changes in breast tissue—known as terminal ductal lobular unit involution—which occur naturally over time and lower future risk of breast cancer. She is also examining associations between PFAS exposure and higher breast density, a cancer risk factor.
Reeves also received a $4.9 million, five-year grant from the National Institutes of Health (NIH) to study whether an accumulation of PFAS in human tissue increases the risk of bone loss and fracture in older adults.
“There is a lot of evidence from animal studies that PFAS chemicals can alter skeleton formation and cause problems with bone development,” Reeves explains. “Our hypothesis is that PFAS chemicals may disrupt the delicate balance between bone breaking down and new bone forming, leading to lower bone mineral density and increased risk of fracture. Fractures in older adults can really cause a downward spiral in their overall health, making prevention critically important.”
Timme-Laragy’s research focuses on developmental toxicology. In 2022, she received a $2.44 million, five-year grant renewal from the NIH to continue her research into how embryonic exposure to certain common PFAS pollutants may put people at risk for diabetes and other metabolic health conditions later in life. She uses a zebrafish model for her research, which is done in partnership with Jeff Doherty and John Clark, UMass Department of Veterinary and Animal Sciences faculty at the Massachusetts Pesticide Analysis Laboratory.
“There are numerous papers in the literature demonstrating links between in-utero PFAS exposure and both type 1 and type 2 diabetes,” says Timme-Laragy. “But many of these studies contradict each other; some actually show that PFAS can be protective of type 1 diabetes. The mechanisms by which PFAS lead to different subtypes of diabetes haven't been parsed out yet in the literature.”
Timme-Laragy’s lab is working to elucidate the cellular and molecular mechanisms by which exposure to environmental pollutants, such as PFAS chemicals, affects the formation and functioning of the pancreas.
“This work is contributing to our understanding of the developmental biology of the pancreas, and has broader implications in terms of potential regulation of certain PFAS chemicals if they’re found to affect the body in certain ways,” she says.
Together with Doherty, Timme-Laragy also works closely with a local community group, Westfield Residents Advocating For Themselves, that is responding to high levels of PFAS in the town’s water supply. The UMass faculty have held community education sessions in Westfield and workshops for legislators on campus, and are seeking funding to better characterize the PFAS contaminating the drinking and surface water around the town’s Air National Guard base.
Soaking Up PFAS
The more researchers learn about the effects of PFAS on human health, the clearer it becomes that prevention is best.
Wang, who recently joined the UMass faculty, is working to develop edible clay-based sorbent materials to help mitigate people’s inevitable exposure to PFAS through food and drinking water. Her research has received funding from the NIEHS.
“This material acts like a sponge, which can grab PFAS in the gastrointestinal tract. Our body doesn’t absorb the clay, so it passes directly through the body and is excreted in stool,” Wang explains.
The product is designed for short-term use during critical periods, such as pregnancy or lactation, or for people living and working in areas known to have high PFAS concentrations. It is a preventative treatment to avoid uptake of PFAS in the body, rather than a therapy to remove the chemical once it’s already settled in.
Wang says the sorbent material can be ingested in different forms, including incorporating it into cooking or using it as a condiment, adding it to water through tea bags, or swallowing it as a powder in a capsule. In previous human clinical trials, carried out in the United States and Africa, the material was shown to be safe for human consumption for up to three months and effective at soaking up aflatoxin, which is a carcinogenic mycotoxin. In addition, study participants reported no unpleasant change to the flavor or texture of food or water. These studies have resulted in multiple issued patents describing clay-based sorbent technologies and global translations into preventive mitigation strategies against environmental chemical exposure in animals and humans.
Currently, Wang is conducting research to develop enhanced sorbent materials that are effective against a broader group of PFAS chemicals. In the future, she aims to test their safety for longer-term use in humans.
Protecting Yourself from PFAS
While completely avoiding PFAS chemicals is unrealistic today, the UMass researchers offered the following tips for anyone wishing to reduce their exposure:
- Install a reverse osmosis filtration system to remove PFAS from drinking water. (Timme-Laragy notes this can be financially out of reach for many people.)
- Replace nonstick pans with stainless steel pans.
- Minimize the use of products with food packaging where possible. For example, make popcorn on the stove rather than in a prepared microwavable package.
- Avoid stain-resistant or waterproof products that are likely to contain PFAS, or seek out brands that have committed to not using these chemicals. The Green Science Policy Institute offers a database of PFAS-free consumer products.
This story was originally published by University Relations.