Lake Superior contaminants face year of scrutiny
In February, the Minnesota Pollution Control Agency will release a blueprint on how it plans to begin to deal with forever chemicals. 7:00 am, Jan. 27, 2021 ×
The Lester River empties into Lake Superior earlier this month. The Lester River and other streams can carry contaminants like PFAS from runoff to the lake. (Steve Kuchera / skuchera@duluthnews.com)
In Lake Superior, the sediment at the bottom of its watery depths tells a story.
It’s where things settle and accumulate, including contaminants. In its way, the sediment serves as a historical record of the lake.
In core samples, research scientists can see when concentrations of, say, mercury were highest, and how now-much-lower concentrations at the top layers of the sample means the contaminant is no longer being so heavily put into the lake.
New Smelt Consumption Advisory for Lake Superior
MADISON, Wis. – Based on recent sampling results, the Wisconsin Department of Natural Resources (DNR) and the Department of Health Services (DHS) are recommending a PFAS-based fish consumption advisory for Lake Superior.
Due to the high levels of PFOS found in the samples, the DNR and DHS are updating the recommended rainbow smelt consumption advisory from an unrestricted amount to one meal per month for Lake Superior.
The sampling completed by the DNR found elevated levels of PFAS (per- and polyfluoroalkyl substances), particularly the compound PFOS, in rainbow smelt in Lake Superior. PFAS are a group of over 5,000 human-made chemicals used for decades in numerous products, including non-stick cookware, fast food wrappers and stain-resistant sprays.