Black mold as it's usually used, refers to a particular kind of stachybotrys spores. The problem with black mold - it's true that black mold - stachybotrys, particularly stachybotrys chartarum, a particular species of it, can have multiple kinds of toxins associated with them. Just because you have stachybotrys, doesn't necessarily mean you have those toxins, because it depends a lot on the growing conditions. But stachybotrys is an indication of conditions that are unhealthy in the indoor environment for a variety of reasons. And so, the presence of stachybotrys is really a huge red flag that there's a serious problem in that environment.
But there are a lot of other spores that have other toxins associated with them that can be just as much of a problem. And they're found far more commonly in the indoor environment, particularly various species of aspergillus or penicillium. Aspergillus and penicillium are one of the most common spores we find in the indoor air. Water damage spores like stachybotrys, and there's a half of dozen of them or so, we usually find them in about five percent of the outdoor samples. We find them in about twenty percent of the indoor samples. But aspergillus and penicillium often make up as much as eighty percent of the spores that we find in the indoor air. There are far higher quantities of aspergillus and penicillium and they can have a lot more damaging toxins associated with them, because of the quantities.
The other thing that we're finding in the indoor air environment is that an air sample is typically a snapshot of time. And if it doesn't happen to be that, let's say you have stachybotrys growing on your drywall, they aren't necessarily throwing the spores out into the air where you can measure them in the indoor air. Until they tend to dry out and get powdery, then they can get some spores out into the air. But the water damage spores are more likely to hold their spores during the time that they're actually growing. So, you can't tell it from an indoor air sample.
Particularly where we find the history of intermittent events, not just a snapshot of the moment, but we find the history is in the carpet dust. And in the carpet dust we can culture and we can, we put it in a series of eight different petri dishes with different agar and incubate them at different temperatures so we can recover whatever is in there.
One of the problems in recovering stachybotrys, which is, we talked about being the black mold, is most agar will not support the growth of stachybotrys. We have an agar that will do that and in fact it's an agar that was patented by our lab director, some many years ago, called this SSI agar. We can use that to recover stachybotrys if in fact it is in the carpet dust.