Michigan officials say they're halfway finished with collecting samples for a statewide study of toxic chemicals that have been detected in 33 states' drinking water.
The Department of Environmental Quality has sampled 892 of Michigan's 1,841 public water systems and schools with their own wells. They are looking for polyfluoroalkyl substances, also known as PFAS.
From those samples, 341 laboratory test results have come in.
Only the city of Parchment's results have exceeded the U.S. Environmental Protection Agency's health advisory level of 70 parts per trillion, which is also the level the DEQ has set to trigger cleanup of groundwater used for drinking.
The Michigan League of Conservation Voters says a tougher standard is needed.
The state is spending $23 million to locate PFAS contamination, identify sources and oversee cleanups.
