MADISON, WI (WTAQ) - Tree swallows in Wisconsin and Minnesota appear to be dying from an old household chemical.
That's according to the U.S. Geological Survey, which studied the effects of PFAS.
The substance is found in no-stick cookware and household stain repellents. Makers of those products started phasing out the chemical 13 years ago, when the exposure concerns were first raised.
Federal scientist Christine Custer says the chemicals are not common anymore -- but high concentrations are still found throughout Wisconsin, Minnesota, and other hot spots.
Researchers studied nests at eight locations. They found that hatching rates for tree swallows were less in place with the most contamination from PFAS.
The study recognizes that other factors may also be causing the declines.