Per- and polyfluoroalkyl substances (PFAS) represent one of the most challenging environmental health concerns of our time. Used in products ranging from food packaging to firefighting foams to stain- and water-resistant fabrics, these chemicals are prevalent in the modern world. While PFAS have made daily life more convenient, they have also introduced numerous health risks due to their ability to persist in the environment and accumulate in the body.
NIEHS Grant Recipient Abby Fleisch, MDMPHphysician-scientist at MaineHealth, conducts critical research on how exposure to PFAS affects health across the lifespan. It linked early exposure to PFAS to an increased risk of obesity, disrupted fat distribution and bone weakness in children. It is important to note that its studies go beyond identifying health risks. Dr. Fleisch also explores how diet and lifestyle changes can mitigate these harmful effects. Based in Maine, a state deeply impacted by PFAS contamination, she combines rigorous research with a passion for empowering communities through education and real-world solutions.
Dr. Fleisch specializes in pediatric environmental health and endocrinology. She is an attending physician in pediatric endocrinology and diabetes at Maine Medical Center, a professor of science at the MaineHealth Institute for Research, and an associate professor of pediatrics at Tufts University School of Medicine. I recently spoke with Dr. Fleisch to learn more about his work on PFAS, its health implications, and practical steps individuals and communities can take to protect themselves. She also shared what inspired her to pursue a career in science.
Chemicals accumulate in the environment, people
Rick Woychik: For readers who may be new to this topic, can you briefly explain what PFAS are and why they are often called “forever chemicals”?
Abby Fleisch: Of course. PFAS are synthetic chemicals used in consumer and industrial products since the 1950s. Their unique properties, such as resistance to heat, water and oil, make them very effective in items such as non-stick cookware, grease-resistant food packaging and water-repellent clothing. Unfortunately, these same properties mean that PFAS do not break down easily in the environment, which is why they are often called “forever chemicals.”
In humans, PFAS can accumulate in the bloodstream, with half-lives of three to eight years, depending on the specific compound. Exposure occurs primarily through contaminated water, food, or air, and almost everyone in the United States has detectable levels of PFAS in their blood.
Exposure to these substances is associated with a range of health problems, including increased cholesterol levels, decreased effectiveness of vaccine antibodies, and certain cancers, such as kidney cancer. There is also strong evidence linking exposure to reduced birth weight. My research has largely focused on metabolic and bone health, examining how exposure to PFAS might increase the risk of diseases such as obesity, diabetes, and osteoporosis.
Diet and lifestyle changes show promise
R.W.: A fascinating aspect of your work is the idea that diet and lifestyle changes can help mitigate the effects of PFAS. Can you expand?
A.F.: Our team analyzed the data and samples from the Diabetes Prevention Program and found that participants with higher PFAS levels at the start of the study had greater weight gain and a higher risk of diabetes and high cholesterol over 15 years of follow-up. As part of this study, we discovered something interesting. Those who followed a structured lifestyle intervention that included both dietary advice and regular physical activity saw a reduction in the effects of PFAS.
Participants in the lifestyle intervention attended regular nutrition and exercise classes. The program encouraged small, achievable changes, such as increasing physical activity and incorporating more whole grains, fruits and vegetables into the diet. These lifestyle changes appear to counteract the metabolic risks associated with PFAS.
In another study, conducted as part of the NIEHS-funded program Viva Projectwe observed that children with higher PFAS levels had reduced bone accumulation from childhood to adolescence. However, adolescents who engaged in bone-building activities, such as regular exercise and adequate calcium intake, appeared to be able to mitigate these effects. This suggests that early interventions can make a difference, even in the face of significant exposure.
Although the evidence is still emerging, there is some indication that a high-fiber diet and nutrient-dense foods may play a role in supporting the body’s ability to combat PFAS-related metabolic disruptions. In the future, my colleagues and I will delve deeper and evaluate which specific diet and lifestyle factors show the most promise. But based on recent findings, I think it’s safe to say that a healthy diet and regular physical activity are generally a good place to start.
Fighting Contamination in Maine
R.W.: You currently work in Portland, Maine. Can you explain how your state is an important setting for studying PFAS?
A.F.: Maine has experienced significant PFAS contamination from biosolids, which refers to treated wastewater that is spread as fertilizer. The use of biosolids is not unique to Maine: it has occurred throughout the United States since the 1980s. Our state passed a law in 2021 requiring the Department of Environmental Protection to conduct testing PFAS in drinking water near areas where biosolids have been spilled. Many people have learned that they are exposed to high levels of PFAS. In some cases, levels were thousands of times higher than normal.
I have studied PFAS for over a decade, primarily at the national level. But when this contamination came to light in my state, the issue became deeply personal. Over the past few years, I have begun to see several pediatric patients with high exposure to PFAS and their families in my clinic. Building relationships with them and working at MaineHealth, where there is a strong emphasis on community-engaged research, allowed me to try to help this community.
Last year, we received funding from NIEHS to partner with the central Maine community, which has been significantly impacted by exposure to PFAS from biosolids. While we know some things about exposure to PFAS and their potential effects, we don’t know much about exposure specifically from biosolids. Our study focuses on measuring PFAS levels in participants’ blood and drinking water, identifying exposure pathways, and examining the mental health effects of learning that your water well contains high levels of PFAS. The specific mental health outcomes we assess are anxiety, perceptions of health risk, and stigma related to exposure.
We hope this research will generate much-needed guidance on exposure mitigation and help build resilience not only in central Maine, but also in communities across the United States impacted by PFAS-contaminated biosolids. We are just beginning to analyze the data from this work and I look forward to sharing our results in the near future.
Supporting Communities and Patients
R.W.: It is admirable that you are working to provide solutions for people in Maine and beyond who have been exposed to PFAS. As a physician-scientist, how do you advise these patients?
A.F.: When I see patients in my clinic who have been exposed to high levels of PFAS, I am comprehensive clinical practice guidelines of the National Academies of Sciences, Engineering, and Medicine (NASEM). The Agency for Toxic Substances and Disease Registry has user-friendly information for clinicians and the public as well, as does an NIEHS-funded project called Research, education, and action on PFAS for community health.
Typically, the first step is to reduce exposure. Most patients come to me knowing that they have high levels of PFAS in their well water, and this is a significant source of exposure that can be mitigated by installing a certified water filter . I also discuss with patients whether they might consume fish or game from areas known to have high levels of PFAS, and review the limitations of “do not fish” and “do not eat” advisories in the central Maine. I also discuss other potential sources of exposure, including breastfeeding for infants and young children and work for older adolescents and young adults.
Next, I talk about the option of PFAS blood testing. The NASEM guidelines provide a clinical monitoring algorithm that recommends additional screening for cholesterol, thyroid function, ulcerative colitis, and testicular and kidney cancer if PFAS blood levels are in the top 9% of the population American. When talking with patients about health effects, I always consider PFAS as a risk factor, similar to smoking or high cholesterol. I want to help patients feel empowered rather than overwhelmed by risks.
People have many concerns about these substances, which is why I am honored to study the health effects of PFAS and use the resulting knowledge to try to improve patient well-being. Communities affected by contamination need concrete solutions, and the environmental health science community can play a major role in helping to achieve this.
(Rick Woychik, Ph.D., directs the NIEHS and National Toxicology Program.)