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Facts About Mold AIHA® December 2011 3 Other things that can be done are to clean and repair gutters regularly, make sure the ground slopes down and away from the home's foundation, and keep air conditioner drip pans and drain lines clean. In addition, in air conditioned buildings in hot and humid climates, vinyl wall coverings on the interior sides of exterior walls should not be used as these materials can trap moisture, resulting in mold growth underneath them. In the case of floods or leaking pipes, any standing water should be promptly removed and water damaged materials should either be dried out and cleaned, or removed and replaced. Porous materials that are wet for more than 48 hours are likely to produce mold growth and should be discarded. In instances where the water damage is extensive, it is recommended that professional help, such as a commercial restoration company, be consulted. Can mold spores contain toxins? Yes. Some of these fungi produce toxic metabolites (mycotoxins), and almost all molds that grow in the built environment can produce triple helical glucan, both of which are toxic to lung cells. Many studies in appropriate laboratory animals have demonstrated that very low exposures of these compounds can result in inflammation. The health effects of breathing mycotoxins indoors are not well understood and they continue to be under study. This research is done to better understand why epidemiological studies consistently show increased asthma among occupants of damp buildings not associated with atopy. Some studies have shown that in agricultural settings, occupational exposure to fungi that produce mycotoxins on grain may result in significant exposures to their toxins. However, it is important to not relate human exposures to mycotoxins in agricultural settings with those exposures that can occur in the built environment (homes and offices). Exposures to mycotoxins in agricultural environments can be at much higher airborne concentrations, and these levels can result in systemic exposure. It should be noted that these agricultural exposures tend to be fungi that do not generally occur in buildings, such as Aspergillus flavus (aflatoxin) and Fusarium graminearum (deoxynivalenol). What is "black mold"? The news media and some contractors often refer to "black mold" or "toxic black mold." It is usually associated with Stachybotrys chartarum, a type of greenish‐black mold commonly associated with heavy water damage. Not all molds that appear to be black are Stachybotrys. The known health effects from exposure to Stachybotrys are similar to those caused by other common molds, and again in high exposure situations (as in agriculture), are known to be associated with severe health effects in some people. Such exposures seldom, if ever, occur in buildings except during remediation activities by people not taking appropriate precautions. Should I be concerned about mold? It all depends on how much. Small amounts of mold growth in workplaces or homes (such as mildew on a shower curtain) are not a major health concern. Large quantities of mold growth, however, are an important public health concern. In addition, mold can damage building materials, finishes, and furnishings and, in some cases, cause structural damage to wood. How do molds affect people? Most people have no reaction when exposed to molds. Allergic reactions, similar to pollen or animal allergies, and irritation are the most common health effects for individuals sensitive to molds. Flu‐like symptoms and skin rash may occur. Exposure to molds may also aggravate asthma. In very rare cases, fungal infections from building‐associated molds may occur in people with serious immune disease. Most symptoms are temporary and eliminated by correcting the mold problem.

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