Black Mold

Stachybotrys chartarum, or "Black Mold," (also known by its synonym Stachybotrys atra) is a greenish-black mold. It can grow on material with a high cellulose and low nitrogen content, such as:

  • Dust
  • Fiberboard
  • Gypsum Board
  • Lint
  • Paper

Growth occurs when there is moisture from water damage, excessive humidity, water leaks, condensation, water infiltration, or flooding. Constant moisture is required for its growth.


Spores do not become easily airborne, so contamination of indoor air is unusual. But at higher levels, health effects such as cold-like symptoms, allergy symptoms, sinusitis, and rashes may occur. There is concern with Stachybotrys because it may be associated with pulmonary hemorrhage in infants, generally those less than six months old. This is a very rare condition that results in bleeding in the lungs. However, a relationship between Stachybotrys and pulmonary hemorrhage has not been proven. Further studies are needed to determine what actually causes acute idiopathic hemorrhage.

Other Black Mold

Not all black mold is Stachybotrys (for example, the black mold commonly found between bathroom tiles is not), but moldy homes are not healthy homes. This mold is rather uncommon in homes, and requires water-soaked cellulose (wood, paper, cotton products) to grow. Keep in mind that all mold is potentially unhealthy, so determining the type is often unnecessary.