Wife,
Please understand that mold behind a wall is 100% toxic 100% of the time. Toxic is not a strong enough word here. You need to get out as i believe you are living in an emergency situation. Please watch the videos below on some people exposed to toxic mold

A few points; first you definitely want to have the house inspected by an environmental consultant who deals with or specialized in mold sampling and remediation. The consultant should take some tape life samples for spore culture and bulk samples and the consultant should take a spore trap sample in the rooms to verify level and type of spores in the rooms. You can find a list of local environmental consultants in. If the mold is toxic mold then you will have to have it taken care of.

Using a bleach and other chemicals even diluted is actually Not what you should use when dealing with mold. To find out more information on why not to use bleach or chemicals to remove mold check out this link:

Also I would not recommend contacting the EPA. If you do and there is toxic mold (Stachybotrys chartarum) depending on the level the EPA would actually evict you from your home and if the levels were bad enough they could burn the home down with everything in it including all of your cloths and any vehicles you have. They have done this in the past.

In the site listed above: Dr. Close Ph.D, P.E. has discovered a new anti-fungal agent that kills mold in the air and on surfaces and has found it very effective in the remediation of mold. There is a lot of information on this site about toxic mold and what you can do about it.

Call the EPA (environmental protection agency).. Gunny is right. There are some molds that are very toxic to humans. They start getting sick and can't figure out why. If that place ever had water damage, that should have been told to you before you bought it. You may end up having to get an Attorney. You might be able to get the Health Dept. to come out and look at it too. Don't let it go…Good Luck.

Have the black mold checked to make sure it is not the type that can kill humans ASAP

Clean it real good with bleach and then you can buy a mold blocker paint to put over it, it is not that expensive and it is sold at most hardware stores, it works wonders.

If it is in the sheetrock, then you must replace it

use bleach dilute with half water