‘Forever chemicals’ show up in Wisconsin residents

The new study led by researchers at the University of Wisconsin School of Medicine and Public Health analyzed serum from 605 adults who donated blood between 2014 and 2016 as part of the Survey of the Health of Wisconsin. Researchers measured traces of per- and poly-fluoroalkyl substances, known as PFAS, which are manufactured chemicals that have been used in everything from fire-suppressing foam to non-stick pans to food packaging.

These compounds tend to “biomagnify” or concentrate in the food chain. In the human body, they bond to proteins in the kidney, liver and blood cells. Earlier studies linked PFAS to human health problems including cancer, changes in metabolism, lower birth weight and changes in puberty.

The study was led by Amy Schultz, epidemiology senior data scientist with the Real-world Evidence to Advance Community Health, or REACH, program at the UW School of Medicine and Public Health. The work also involved collaboration with researchers at the Wisconsin State Laboratory of Hygiene at UW–Madison and the Wisconsin Department of Health Services.

“The Upper Midwest is an area of special concern because of our history of manufacturing and because of a strong tradition of fishing,” Schultz said. “While other localized studies have identified eating caught fish as a source of PFAS exposure, this was the first population-based biomonitoring study in the Great Lakes area to examine what other factors may also be associated with PFAS levels. However, even in this statewide study, we found an association between PFAS levels and eating caught fish.”

The study, published this month in the Journal of Environmental Research, randomly selected frozen blood samples from those who had volunteered for the Survey of the Health of Wisconsin, which is now called the REACH Program. State lab scientists tested the serum for 38 types of PFAS using a new method developed by the lab to detect the substances at lower levels, according to Meshel Lange, laboratory manager with the State Laboratory of Hygiene and co-author of the study.

“What made this study unique and exciting was that our partnership with REACH allowed us to conduct the first study to show statewide assessment for exposure to these potentially harmful chemicals,” she said.

The study also investigated correlations between PFAS levels of volunteers and their environment, eating habits, lifestyle, race, income level and other demographic data. The participants were asked about many potential exposures, including how much fast food they ate, how often they eat microwaved popcorn – because PFAS compounds were not banned from use in bag linings until February 2024 – and whether they live in a city or a rural area.

The researchers found the strongest link between higher PFAS levels and older age, male gender, non-Hispanic white race, higher income levels and eating caught fish. Those who ate microwaved popcorn had somewhat higher levels, while eating fast food seemed to have no effect.

Knowing who is most likely to be affected by PFAS can help researchers target public health messaging and interventions, but this study was unable to determine whether there is a cause-and-effect relationship, Schultz said.

“This is just a first look at understanding who is more likely to be exposed to PFAS in Wisconsin,” she said. “Overall, PFAS averages were low, and just because we found an association with eating caught fish with higher PFAS serum levels does not mean anglers should stop eating local fish. Additionally, even though we did not find an association between eating fast food and PFAS, we know fast food containers are a source of exposure.”

Future studies will build off this one to more thoroughly examine trends seen here, she said.

The research team previously found that Wisconsinites have lower PFAS levels compared to the national average and published their findings in January 2024 in the Journal of Exposure Science and Environmental Epidemiology.