The new law signed by Governor Granholm requires all children enrolled in the Women, Infants and Children assistance program to be screened for lead. More than half of the state's 227,000 residents in the federal assistance program are children.
Granholm announced the bill signing Wednesday.
"Exposure to lead can seriously impact a child's health and development," Granholm said in a statement. "Testing and treating children, especially those who live in high-risk areas, is a critical step to ensuring that they can get off to a good start in life."
The bill was sponsored by Sen. Martha Scott, a Democrat from Highland Park.
State government has set a goal of screening at least 80 percent of children served by the state's Medicaid program by 2007.
The new law should help the state meet that goal, Granholm said.
The law could cost the state up to $500,000 for initial screening and follow-up testing, according to an analysis by the nonpartisan House Fiscal Agency.