DETROIT — Eight people were killed after tornadoes tore through parts of Michigan and Oklahoma late last week, leaving survivors facing immediate and long-term health risks. An EF3 twister with winds exceeding 150 mph was reported near southern Michigan’s Union City on Friday night, where three people were killed and at least a dozen others were injured. A fatality occurred in nearby Cass County after a 12-year-old boy who had been injured by another tornado died at a hospital. In Oklahoma, two people died when a tornado hit a home near Beggs, south of Tulsa, and at least two others were hospitalized. A mother and daughter were also killed in their car after being hit by a tornado in Fairview, about 100 miles northwest of Oklahoma City, according to local news reports. Hospitals and emergency responders across both states treated victims for trauma injuries ranging from cuts and fractures to head injuries caused by flying debris and collapsed buildings.…