What is Stachybotrys?

Stachybotrys is a fungal genus with one notable representative: Stachybotrys charatrum, the notorious “black mold” which can infest structures, especially homes. This mold is notable because it has been known to produce substances known as mycotoxins, under the right environmental conditions. These substances can cause severe illness in people, especially if individuals are exposed repeatedly to mycotoxins over an extended period of time.

Molds in this genus like environments which are rich in cellulose, such as paper pulp, wood, and straw. They are greenish to black in color, and the colonies develop a furry texture over time. Stachybotrys is a very slow growing mold which can be out competed by other mold species, but given the right environment, it can grow copiously and cause a great deal of damage. In order to thrive, Stachybotrys needs a very high-moisture environment, which is a fact that people can use to their advantage.

Stachybotrys itself is not toxic. The mycotoxins are produced in the spores of the mold, and only under certain conditions. If the environment stays wet, the spores tend to stick to the fungal colony, which means that they will not spread and cause health problems. As the mold dries out, however, it releases its spores, and mycotoxins can also be released when the mold is disturbed. People who inhale Stachybotrys spores can experience headaches, fever, fatigue, vomiting, diarrhea, and infections of the mucus membranes in the lungs, nose, and mouth. At low levels, people may simply feel a generic sense of malaise, making it difficult to pin the cause on Stachybotrys.

This mold often grows inside walls and in other hidden areas, which makes it very difficult to identify, because people cannot see it. After flooding or extended periods of chronic moisture, the mold can start to grow on the outside of the wall, becoming readily apparent to the naked eye. If people can see or smell mold in a structure, steps need to be taken to remove it immediately. In cases where Stachybotrys infestation is suspected but not readily provable, an air sampling device can be used to test for the presence of the mold.

To prevent Stachybotrys colonization, environments should be kept warm and dry, with good air circulation. In the event that a structure is flooded, as much flood-damaged wood and other material as possible should be removed, to give the structure a chance to dry fully and air out. If the mold does start to invade, the infested sections of a structure should ideally be taken out and burned to get rid of the mold. People can also try washing and bleaching the area where the mold is visible, but this technique is not always effective, as it may not target hidden mold, and it can add to the moisture, promoting the growth of Stachybotrys in the infested area.