“A common misperception is that killing mold, which is a relatively easy task, eliminates risk from contaminated environments or items. Unfortunately, this does little to decrease the risk as nonviable fungal spores, fragments, and mycotoxins remain present and, due to their structure, such as with an epoxide ring,  they can be extremely difficult to destroy.”
That is a quote from one of my favorite articles on mold, found here.
Back in 2008 when we were busy “killing” mold in our mold house, setting the stage for me to get incredibly ill, that article had not even been published yet!
So what does “killing” mold do? Among other things, it can cause the toxins to become more airborne. I do not know why exactly this happens, but some people think it’s because the mold is trying to “fight back” and save itself. Kind of like a skunk spraying or a snake biting. Or kind of like how some plants are toxic–people and animals learn to leave them alone. Only mold has a unique ability to shoot its toxins into the air.
For materials in a home, there are at least three scenarios.
Scenario 1: mold has grown on dirt on a basically non-porous surface, such as a hard plastic window sill. Wipe away the dirt, and the mold goes with it. No need to use any kind of “killer” at all, just wipe it away. I cannot guarantee this will work, but it is likely to, because the worst, most tenacious molds are not likely to grow on windowsills (or tubs or sinks). They usually like dark, very wet, hidden places such as walls with a hidden leak.
Scenario 2: mold has grown on a porous surface, such as drywall or wood beams. If sprayed and wiped, some of the mold may come off, but the roots will remain in the drywall. Even if you cannot see them and even if mold does not grow back, the roots remain and give off toxins. These toxins are so small they go through paint, flooring (maybe not porcelain tile though probably through the grout), walls, ceilings, thick cement, etc.
So far, we have found that aluminum foil WILL block toxins. I would guess most metals would, too, as well as glass. But just be aware that one would not want to completely foil over a wall because walls need to breathe to avoid moisture getting trapped in the wall and causing more mold.
From the article above: “Research has shown that none of the commonly used methods for cleaning water-damaged materials such as bleach, ammonia, ultraviolet (UV) light, heating, and ozone were found to completely remove mold and mycotoxins from water-damaged building materials .”
So, drywall with mold should be removed. Wood beams may be (with Hazmat practices) sandblasted, dry-ice blasted, or planed. Take off a thin layer of the wood along with mold roots.
Scenario 3: mold has grown nearby (in a wall) and its spores and toxins have landed on objects.
It will grow in clothing, mattresses, wood furniture, etc. But even on non-porous items, such as electronics, the spores and/or toxins will land and “stick” there until wiped off. (Some cannot be wiped off. 🙁 ) They are invisible (certainly no visible mold growth) but can be very dangerous to the body.
We were able to salvage some things from our mold house by washing thoroughly, but we also did not have the most “sticky” kinds of mold in our house.
“Dead” mold is just as toxic as viable mold spores are. Dead mold can put out toxins at a terrible rate.
So, don’t kill mold; remove it and you will be the healthier for it.
Christa Upton Black Hills Picture Books Edgemont, SD 57735