Landlord putting me and my two disabled teens in danger

I am a cancer patient and my children have autism, upper respiratory problems, along with other health problems. The A/C has been out for nearly one week; there is soot coming through the vents (which my doctor states is dangerous, in particularly for me and for my children); dirty water rises in both kitchen sinks when washing machine drains. The kitchen was flooded twice and still no repair was made. There is soot from the furnace on every wall and ceiling that we breathe every day. There are flying ants that come through my bedroom window every year which infected my son and led to a doctor visit and antibiotics. . The air ducts have not been cleaned, which produces the soot. I must replace my curtains, because they are black with soot. I have no money, due to my disability as well. How can I place my rent in escrow until the repairs are completed..