Molds proliferate in environments that contain excessive moisture, such as from leaks in roofs, walls, plant pots, or pet urine. 4-6 Many building materials are suitable nutrient sources for fungal growth. Cellulose substrates, including paper and paper products, cardboard, ceiling tiles, wood, and wood products, are particularly favorable for the growth of some molds. Other substrates such as dust, paints, wallpaper, insulation materials, drywall, carpet, fabric, and upholstery commonly support mold growth. 3 Molds also may colonize near standing water.
Some indoor molds have the potential to produce extremely potent toxins called mycotoxins.
13 Species of mycotoxin-producing molds include Fusarium, Trichoderma, and Stachybotrys . In general, the presence of these molds indicates a long-standing water problem. The toxic effects from mold exposure are thought to be associated with exposure to toxins on the surface of the mold spores, not with the growth of the mold in the body. Until recently, there was only one published report in the United States linking airborne exposure to mycotoxins with health problems in humans. The investigators documented that this mold was producing trichothecene mycotoxins.