Pollution caused by sulfate has put wild rice beds in northern Minnesota on the Minnesota Pollution Control Agency's impaired waters list, MPR reports.
Sulfate is a chemical that grows naturally in soil and water, but researchers say much of the sulfate found in the affected areas is coming from iron mining, causing a major decline in wild rice beds.
Northland's NewsCenter says the MPCA is halfway through a two-year study that could change environmental standards concerning wild rice and sulfate. The current standard adopted in 1973 is 10 milligrams per liter.
MPR says the Minnesota Chamber of Commerce is suing to loosen the standard.
Wild rice is sacred to the Ojibwe of Minnesota. The Fond du Lace band of Chippewa fear more pollution could wipe out important stands of wild rice.