The mushrooms in your grocery store have much in common with the black mold that forms on stale bread and mildew that collects on damp shower curtains. These life forms belong to the Kingdom Fungi, a group of more than 100,000 known species. Fungi do not make their own food like plants do. They get it from other living organisms. Their main role in the ecosystem is to break down dead materials. Without fungi, the earth would be full of dead things: dead leaves, trees, dead insects and dead animals. The same enzymes that help fungi to break down wastes and dead organisms also let them attack wood, fiber, and food. Various molds cause great damage to stored goods and building materials each year. These same molds cause problems in housing, affecting the health of residents and the structural soundness of the buildings.
Fungi are classified into major divisions, largely based on their method of reproduction. A commonly occurring example of a zygomycota is black bread mold. The ascomycota division includes over 30,00 species, including some yeasts, powdery mildews, most of the blue-green, red and brown molds, and the edibles morels and truffles. Basidiomycota include the most familiar of the fungi: mushrooms, toadstools, bracket fungi and puffballs, as well as some plant parasites such as rusts and smuts. Oomycetes are microscopic water molds. A group called deuteromycetes has stages in the life cycles which place it in different groups at different times. About half of the species that affect human health are in this group.
Mold can be found on plants, dry leaves, and just about every other organic material. Man has found some molds to be useful, such as those used to make antibiotics, beer, cheese and wine. Some molds are known to be highly toxic when taken in with food, such as the types that invade grains and peanuts. Still others cause negative health effects such as asthma or allergic reactions when their reproductive spores are inhaled. Most of the mold found indoors comes from outdoors. The lightweight spore's float in on air currents often being carried long distances before settling on some surface. If mold spores land on a suitable surface, they will begin to grow. Molds need certain things to thrive, including moisture, food, and a surface to grow on. They like the same room temperature that we do! Molds cn be found throughout the house, but are commonly found where there is moisture, such as in the bathroom. Mold growth can often be seen in the form of discoloration, and can be many colors: white, orange, pink, blue, green, black or brown. When molds are present in large quantities (called colonies), they become a health concern. Molds can generally be divided into 3 groups based on their health effects: Allergenic, Pathogenic and Toxic.