Mycal Anderson, 9, of Flint, seated on the lap of  mother, Rochelle Anderson, reacts to having his blood drawn for lead testing in January. (Conor Ralph/The Flint Journal-MLive.com via AP)

The Obama administration announced Thursday that it would extend Medicaid coverage to 15,000 children and pregnant women in Flint, Mich., affected by lead that has poisoned their tap water.

The U.S. Department of Health and Human Services also said that another 30,000 current Medicaid recipients in the city would be eligible for additional services under a five-year waiver from rules that govern the program.

The arrangement will provide recipients with a variety of free health services, including monitoring for the level of lead in their blood and behavioral health treatment, HHS said in its announcement. The programs will be offered to children up to the age of 21 and pregnant women who were using Flint water from April 2014 to a date yet to be specified by Michigan Gov. Rick Snyder (R). Families must earn less than $97,200 a year to qualify.

People with higher incomes would be allowed to buy into a state program to receive the same services.

"The expanded benefits available through this Medicaid waiver give parents in Flint access to this type of care and support that may be needed to help their children overcome possible effects of high lead exposure," Nicole Lurie, assistant secretary for preparedness and response at HHS, said in the agency's statement.

Flint's drinking water was poisoned by lead in April 2014, when the city switched to the Flint River for its supply, and state officials failed to ensure that anti-corrosive chemicals were added to the water. That allowed lead from aging pipes to leach into the water supply. Many in the city are drinking only bottled water.

Lead is especially dangerous to the developing nervous systems of children under 6. It can cause learning disabilities, behavioral problems and other ailments that may not appear for years.

Mona Hanna-Attisha, a Flint pediatrician who first alerted the public to elevated lead levels in many young children, has been calling for government to fund a range of health services for all Flint youngsters because it is impossible to tell now which of them may be affected in years to come.

"We cannot sit back and wait 20 years to see the consequences of lead poisoning in our schools and in our criminal justice system,” Hanna-Attisha, director of pediatric residency at Hurley Children’s Hospital, has said.

On Wednesday, HHS announced a $3.6 million expansion of the Head Start program for some children exposed to lead in Flint.

In a statement on his web site, Snyder said that "providing important health resources to Flint residents will help us better mitigate the risks of lead exposure and identify long-term health challenges.”

Sen. Debbie Stabenow (D-Mich.), who had called on HHS to allow the Medicaid expansion, said in a statement on her web site that "today’s announcement is a very significant step forward to ensure thousands of innocent children and pregnant moms have the comprehensive health and nutrition services they need to address the serious lead-exposure issues they may face."