A group of Bronx parents says they plan to sue the Department of Education if toxic chemicals discovered at some schools are not cleaned up.

A New York Daily News investigation found that many schools built in the 1950s added illegal toxic chemicals known as PCBs to caulk around window and door frames. Some Bronx parents now say their children have been getting sick from the contaminants.

The Department of Education says the chemicals aren't harmful unless they become airborne. A department spokesperson adds they're working closely with the Environmental Protection Agency to address the problem.

But parents from schools such as P.S. 178 in Co-op City say the city has known about the contamination for more than a year and has done nothing about it.

"If we don't see action soon, we will be compelled to file a lawsuit on behalf of parents to force the Department of Education's hand on the matter," says Miranda Massie, a staff attorney with New York Lawyers for the Public Interest.