Black mold found in ac/heat ducts

We have had health problems since we moved itno the townhome. The landlord was informed by the HVAC compnay when they replaced the ac/heat unit that he had a black mold problem in the return area and repairs were needed. He did a very bad job repairing the area and we were informed by the HVAC guys that the mold could come back very easly and they felt it was still present. We recently did a mold test and we have mold in the ducting system and if we run the heat we start to cough and get sick. Can we get out of this lease and move asap. I do not want him to rent this place again until repairs are made. So my question is "Who do I contact to report this home and how do I break the lease so that we can get away from this mold"?