They say nothing lasts forever, but the harmful substances toxicologist and AAAS Member Jamie DeWitt, Ph.D., advocates for the government to regulate might prove otherwise.
“What is in the environment now is likely to endanger us as well as future generations,” says DeWitt, pointing to a class of 10,000 human-made compounds that don’t degrade easily.
Appropriately dubbed “forever chemicals,” PFAS – short for “per- and polyfluoroalkyl substances” – are present in everyday products from nonstick cookware to food wrappers and water-repellent clothing.
Their molecules, chains of carbon and fluoride bonded together, persist in soil, air and drinking water for what some estimate could be centuries. Research links continued exposure to adverse health effects on humans and animals including cancers, liver damage and high cholesterol.
In her lab at East Carolina University, DeWitt, Professor of Pharmacology and Toxicology, studies the ways PFAS undermine the effectiveness of vaccines similar to the ones critical to ending the COVID-19 pandemic.
Vaccines deploy weakened or inactive versions of a virus to prompt an immune response, conditioning the body to fight off the pathogen in the future.
Using experimental models, DeWitt’s team found that PFAS inhibit this process by suppressing B cells, blocking their ability to produce antibodies.
“We’re still trying to understand the molecular changes that take place at the cellular level of the immune system so we can understand why B cells seem to be targeted,” she says. In future research, DeWitt hopes to dive deeper into the mechanics of this interaction.
This and other mounting evidence against PFAS as a public health risk presents a case of history repeating itself. More than 50 years ago, DDT dominated headlines before the United States government banned the toxic insecticide at the urging of scientists and environmental groups.
“We’re fighting the same fights over again,” says DeWitt. “I wish that scientists could come up with solutions that are agreeable to the people being exposed as well as those who depend on hazardous chemicals for their livelihoods.”
Striking that middle ground – not necessarily strict bans – remains the focus of DeWitt’s advocacy efforts. As an academic scientist, she appreciates the freedom to talk openly with journalists and communities about the risks posed by harmful chemicals.
DeWitt is a member of the Global PFAS Science Panel, a collaboration of scientists, researchers and policy analysts dedicated to enhancing the understanding of PFAS to facilitate informed decision-making.
The group promotes its “essential use concept” to identify when the application of a hazardous chemical should be prohibited because it’s not critical to the health and safety of society or if there are less dangerous, functional alternatives. Maine adopted the approach this summer when it became the first jurisdiction in the world to ban the sale of products containing PFAS.
To spread awareness, DeWitt also testifies for lawmakers on the effects of PFAS and serves as a plaintiff’s witness in environmental lawsuits. In one such case, the state of Minnesota sued 3M, alleging that the company knowingly contaminated groundwater sources with PFAS, putting residents at risk. DeWitt provided a report summarizing known toxicities for the lawsuit, which settled for $850 million in 2018.
Many PFAS haven’t been studied at all, she says, adding that awareness among young people is key to understanding more about the risks these chemicals pose. In a project led by Kathleen Gray, Ph.D., at the University of North Carolina’s Institute for the Environment, DeWitt looks forward to working with Gray’s team to develop educational materials on PFAS for grade school children.
Outside of the lab, DeWitt speaks to students about the ways scientists can impact society. She hopes her career and experience might inspire the next generation to pursue roles in the scientific community that weren’t on her radar as a kid growing up in rural Michigan.
At a young age, DeWitt always envisioned herself wearing a lab coat but didn’t have exposure to scientific job opportunities beyond veterinarians and doctors.
After high school, DeWitt attended Michigan State University, majoring in environmental science and biology. Through a registration error, she ended up taking a class on waste management.
“It was my first taste of how science and policy can work together and improve the environment,” she says. “As I learned more about toxicology, I realized it was a perfect science for me.”
After college, DeWitt attended Indiana University to get Ph.D.s in environmental science and neural science. Later, she pursued postdoctoral fellowships, including one at the U.S. Environmental Protection Agency (EPA) focused on toxic organotin compounds, chemicals based around carbon-tin bonds that leach out of PVC pipes.
Shortly after, she switched to studying perfluorooctanoic acid, a specific PFAS identified by the agency as a higher priority.
“One of the things that I learned from my postdoc at the EPA is that regulatory scientists have to be very flexible and quick to adapt to change,” says DeWitt, who soon after started her work at East Carolina University in 2008.
“I don’t know that it would be possible to ban PFAS and stop using them altogether right now,” she says. “I want to work cooperatively on solutions that benefit society and the environment.”