Can you explain the difference more? I know outdoors is usually the better kind. What if a building got wet, is that ever okay mold? I know most wood gets wet during the building process, or if you had a flood or leak, can it dry out and be ok? How do you determine, by taking a sample and culturing it? Can't you clean up black mold and some other molds and it's okay? Is it too hard to get all of it?
I tend to mentally divide "Mold" into three categories: benign molds (which make no toxins that are dangerous to humans, or at most very low levels of them), moderately toxic molds (the ones that were recognized in the literature prior to about 1995), and very toxic molds (the ones that have emerged in recent years).
Outdoor molds are not necessarily benign. Moderately toxic molds seem to be fairly common, but the dilution with large quantities of fresh air seems to nullify many of their effects.
In some cases though, molds making toxins that are really problematic for people (or at least, for people with CFS or mold illness) do grow outdoors. For instance, the chemical Roundup (glyphosate) is known to kill off a wide variety of microorganisms in the soil, allowing certain other microorganisms to grow unchecked. One of these is Fusarium, a toxic mold that creates a trichothocene toxins similar to the one made by Stachybotrys ("black mold"). Personally, I have a difficult time traveling to the Midwest, and the agricultural regions feel worse to me than the cities. I believe that the presence of this mold is part of the reason why.
It's the belief of some of us that particularly dangerous toxins made by molds or other microorganisms also are present in the sewers in some places, and that these can emerge into the outside air. Scattered other outdoor places (especially those that have been damaged with particularly toxic chemicals) can be problematic with these toxins as well.
Indoor molds also can be basically non-toxic, somewhat toxic or very toxic. However, the somewhat and very toxic species tend to dominate the non-toxic ones in most indoor environments, especially in modern buildings using such things as wall insulation, drywall and HVAC systems. As in the outdoors, the chemicals used inside homes seem to slant the balance toward the more toxic ones. Certain molds have evolved to be able to grow on mold-resistant paint, for instance. These are not normal molds, and thus may not be ones that our bodies are adapted to evolve (and, from what I've heard, do produce particularly problematic toxin).
I don't know a terribly lot about buildings, but it certainly is true that many buildings get wet before the roof it put on. Apparently a bit of mold growing on solid wood studs is not considered to be a problem, in the building industry. (I was told once that that kind of mold tends to be aspergillus or similarly moderately toxic molds.) Much more problematic is when buildings are made of pre-fab construction and then get wet, because the processed wood is more likely to grow dangerous species such as Stachy. Obviously if a building is already mostly finished and a roof problem occurs, dangerous molds can grow pretty rapidly.
There are labs that can identify molds, but most people in the construction business don't bother to do that. With the worst types of molds, such as Stachy, cleaning or painting over the molds does not help. The affected sections need to be removed, serious mold professionals seem to agree. Otherwise it grows back really easily.
Best, Lisa
Chemicals or building materials? I think I'm like that person. Some kinds of mold I am good with? Not good with black mold.
