failure to make repairs/mold

On Dec 17th,2006 my son found several large areas of mold growing around the window casings in his apartment. Not just a few spots - we're talking the entire window casing and creeping into the wall on all three windows in his apt. This is due to leaking windows/condensation problems reported to the landlord, but never fixed. The mold was reported the next day, and it appears that maintenance may have cleaned at one small area,but ignored the rest. We took samples to a lab to be tested from all window casings and the heating duct. The tests came back positive for several types of mold. My sons wife is in her first trimester of pregnancy and they have since moved in with us, abandoning the apt. Can they legally break the lease now that the landlords have failed to respond and the mold has caused health problems for both my son and his wife (upper resp infections, eye infections, etc.)?

It is permitted to break the lease if they have failed to comply with the lease and/or there are health, noise or safety concerns--but save all information, evidence etc. in case they dispute the situation and try to take you to small claims court.