Hundreds of formerly homeless families have been exposed to lead paint poisoning and the Legal Aid Society is demanding the city fix the problem.

The Legal Aid Society wants the New York City Department of Homeless Services to test the units it placed families in from December 2004 to November 2006, according to a Daily News report. The organization is demanding the city move families that are still living in the housing or face a lawsuit.

The DHS recently admitted to the problem of lead paint in units where it placed families enrolled in its Housing Stability Plus program, according to reports. The program, which the city ended in April, is being replaced with another program.Lead paint has been known to cause developmental delays in children.