Scientists advising the state of Michigan recommended Thursday that it adopt what officials said potentially would be some of the strictest and most far-reaching drinking water standards for "forever chemicals" in the U.S.
A science advisory workgroup identified limits for seven types of the widely used man-made compounds, which are called perfluoroalkyl and polyfluoroalykyl substances, known collectively as PFAS.
The federal government has a nonbinding health threshold of 70 parts per trillion for two phased-out forms of the contaminant, PFOA and PFOS. If Gov. Gretchen Whitmer's administration sticks with the scientists' suggestions, the state's tap water standards for those compounds would be 8 and 16 ppt.
"These findings are very close to the handful of other states that have made PFAS contamination a priority and underscores the need for federal leadership on research and standard-setting at a national level," said Steve Sliver, executive director of the Michigan PFAS Action Response Team.
PFAS increasingly have turned up in public water supplies and private wells around the country. They are used in firefighting foam, nonstick pots and pans, water-repellent clothing and many other household and personal items.
There is growing evidence that long-term exposure to the compounds can be dangerous, even in tiny amounts. The state Department of Environment, Great Lakes and Energy is expected to issue final rules by April 2020.
Environmental groups generally welcomed the recommendations. One called it a solid step, though another — the Natural Resources Defense Council — said it would push to strengthen several recommendations it considers to be too weak.
"The state should go as far as the scientific data will allow, as part of its obligation to protect Michigan's drinking water from chemicals that harm health," said Cyndi Roper, a Michigan-based senior policy advocate with the organization.
An industry group, the American Chemistry Council, credited the workgroup for not taking a one-size-fits-all approach to regulating individual compounds. But it questioned the Whitmer administration's "overly aggressive timeline" to establish PFAS standards, saying it would not allow for enough public discussion and deliberation "about any potential uncertainty in the science that is separated from politics."
The Environmental Protection Agency plans to consider setting nationwide limits on the chemicals. But Whitmer, a Democrat, is not waiting for the Trump administration to act.
Michigan has 58 sites with known sources of PFAS contamination, including areas near military installations and industrial landfills.