A recent study found a group of human-made chemicals called PFAS, or per- and polyfluoroalkyl substances, present in the rain, air and waters in the Great Lakes Basin. They don’t break down easily in the environment and are often called “forever chemicals.”
Marta Venier, an environmental chemist and professor at Indiana University, said researchers wanted to know what role atmospheric deposition played – both as rain and through particles in dry air - in bringing PFAS into the Great Lakes.
The researchers collected samples of rain, air, and water from each of the Great Lakes and analyzed them for the presence of 41 PFAS chemicals.
“One of the results was that the levels of PFAS in precipitation are really similar at all of the locations,” Venier said.
That included both remote locations, such as Sleeping Bear Dunes National Lakeshore and Eagle Harbor in the Keweenaw Peninsula, and highly industrialized and urban areas like Chicago and Cleveland.
“Finding that the levels of PFAS at all of these locations which are so different, were similar, was somewhat different from what we’ve seen from other chemicals,” Venier said, adding that the levels of many other pollutants in rain tend to be higher in areas with higher populations.
But the amounts of PFAS in the air show a different pattern, she said.
“For those samples, the levels were dependent on the location,” Venier said. “They were higher next to urban centers and lower at the more remote areas.”
The study also found differences in the amount of PFAS in the lakes, with the highest levels in Lake Ontario, followed by Lake Michigan and Lake Erie. Lake Superior had the lowest amounts.
Many consumer products, including “the rain gear that we wear to go out to protect ourselves from the rain, or camping gear, or cookware or cosmetics” contain PFAS, Venier said.
Venier said drinking water in some areas is contaminated, and fish in contaminated lakes may be unsafe to eat.
She said people who fish should look at fish consumption advisories in their area as PFAS are some of the chemicals driving those warnings. Other chemicals of concern include mercury, dioxin and PCBs, also known as polychlorinated byphenyls, according to the Michigan Department of Health and Human Service’s Eat Safe Fish Guides.
PFAS are a group of about 15,000 chemicals that are used in many industrial and consumer products, including paints and non-stick products, food packaging, fire fighting foam and many others.
They are found in drinking water, food, soil, and in the blood of people and animals all over the world, according to the U.S. Environmental Protection Agency.
While the health effects of most PFAS are not well studied, some of the chemicals are associated with health problems including kidney and prostate cancers, increased cholesterol and risk of obesity, decreased immune effects and fertility, and others, according to the EPA.
In April the EPA announced national drinking water standards for six PFAS chemicals. Public water systems have until 2029 to comply with the new standards.
Michigan formed the Michigan PFAS Action Response Team (MPART) in 2017 and has been regulating seven PFAS in drinking water since 2020.
In April State Representative Penelope Tsernoglou (D-East Lansing) introduced the Hazardous Products Act, which, if passed, would limit the sale and distribution of PFAS-containing products in Michigan starting in 2027.