PFAS plume found in Green Bay, Lake Michigan waters

By: - January 4, 2023 6:00 am
PFAS sample testing bottles | Photo by Department of Environment, Great Lakes, and Energy

PFAS sample testing bottles | Photo by the Michigan Department of Environment, Great Lakes, and Energy

A plume of per- and polyfluroalkyl substances (PFAS) has made its way into Green Bay, Lake Michigan, according to a new study. The study, conducted by the University of Wisconsin-Madison Department of Civil and Environmental Engineering, tracked the movement of the so-called “forever chemicals” through Wisconsin’s groundwater and found chemical evidence linking it to a large PFAS contamination site in Marinette.

PFAS are man-made chemicals that have been used in a variety of products, from non-stick pans to firefighting foam, for decades. The chemicals do not degrade in the environment, and have been linked to a slew of chronic diseases including thyroid disorders, birth defects, and cancers in humans and other animal species.

The study used a forensic technique called PFAS fingerprinting that enables researchers to identify specific PFAS contaminants and their sources by comparing the ratios of individual PFAS compounds.

“We used a forensics approach to investigate how the PFAS fingerprint from an industrial source changes after undergoing environmental and engineering processes,” said Christy Remucal, a researcher who conducted the study, said in a UW press release. Remucal and postdoctoral co-investigator Sarah Balgooyen published their work in the journal Environmental Science & Technology. The study was funded by a grant from the Wisconsin Sea Grant College Program.

Green Bay is one of the largest bays on the Great Lakes and is part of an interconnected system that serves some 30 million U.S. and Canadian residents — punctuating the concern over PFAS contaminating the water system.

The fingerprinting study found that the PFAS contamination in Green Bay is nearly identical to PFAS associated with the Tyco firefighting foam testing site in Marinette, where the Wisconsin Department of Natural Resources has been overseeing a contamination investigation and cleanup for several years. The Wisconsin Department of Justice filed a lawsuit last year against Tyco in connection with the contamination.

The new study also confirmed that PFAS is present in streams near some agricultural fields. Researchers believe this PFAS contamination may have originated from the treated biosolids many farmers use to fertilize fields, according to the report.

Biosolids are wastewater treatment byproducts and tend to be rich in nitrogen and phosphorus. Since PFAS in wastewater undergo extensive processing, some PFAS will tend to concentrate in biosolids during treatment. Wisconsin has long dealt with water contaminated by the byproducts of fertilizers and manure.

“Treated biosolids are commonly spread on fields all across Wisconsin,” Balgooyen notes. “This information may impact how municipalities across Wisconsin and other states approach the use of biosolids as an agricultural fertilizer.”


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Isiah Holmes
Isiah Holmes

Isiah Holmes is a journalist and videographer, and a lifelong resident of Milwaukee, Wisconsin. His writing has been featured in Urban Milwaukee, Isthmus, Milwaukee Stories, Milwaukee Neighborhood News Services, Pontiac Tribune, the Progressive Magazine, Al Jazeera, and other outlets.