There’s a new threat to the health of the Great Lakes.

Microplastics – tiny snarls, tangles and shreds of plastic – are appearing by the hundreds of thousands in western Lake Superior. Researchers with the Large Lakes Observatory at the University of Minnesota-Duluth said that amounts don’t approach what’s found near Hawaii in the Great Pacific Garbage Patch, but are more than what’s been found in the North Atlantic. Researchers still are not sure where the tiny particles are coming from, but believe one source is household laundry. Synthetic fabrics break down in the wash but washing machines, unlike clothes dryers, don’t have lint filters. And unlike natural fabrics, these fibers don’t break down in the water.