Mold and other fungi: Friend or foe? Many of us enjoy eating bread and having an occasional beer produced thanks to the fermentation process of the fungus, yeast. Mold, another type of
fungus, is used in the production of blue cheese and is also nature's recycler - decomposing organic material that would otherwise continue to accumulate on our planet. The mold Penicillium
produces a metabolite, penicillin, which was discovered in 1929 to be an effective inhibitor of bacteria and helped usher in the modern age of antibiotics. Based upon these facts, it sounds like mold might be our friend and, after all, we've lived together on earth for a long time. However, in history we see many examples of mold portrayed as a mortal enemy of man: the ergot (a rye grain mold) that produced poisonings, gangrene, and abortions in Europe during the Middle Ages, and the many cases recorded of domesticated livestock being poisoned and killed by moldy grain and crops. In 1960, for example, more than 100,000 turkeys in England died from ingesting moldy peanuts that had been mixed into their feed. This particular mold,
Aspergillus flavus, produces a metabolite called "aflatoxin" which has been found to be not only toxic, but one of the most potent carcinogens known to man. So - one can argue that mold is both
friend and foe depending upon the situation. However, recently the print and television media have been loaded with stories of "toxic" or "killer" mold found in homes and commercial buildings which has
been blamed for ailments ranging from skin rashes and hair loss to nervous system damage and death. Is mold really hazardous?
To put it into perspective, the majority of the health effects reported from mold
exposures are allergic reactions. Typical symptoms might include a runny nose, eye irritation, cough, congestion, and dermatitis. However, some individuals with suppressed immune systems such
as AIDS patients, cancer patients undergoing chemotherapy, and the chronically ill may be at risk for systemic infections and "fungal balls" forming in
the lungs. There are some types of mold that can produce toxins (mycotoxins), such as those mentioned earlier and including species of Stachybotrys, which can
cause serious adverse (and even lethal) effects in humans. However, it is still in debate in scientific circles whether those mold species typically found indoors are
capable of producing these effects through inhalation exposure. In general, The Centers for Disease Control and Prevention (CDC) cautions that all molds, not
only the so-called "toxic molds", should be handled appropriately and their presence should be taken seriously. Of course, aside from potential health effects
to the inhabitants of a building, mold can also destroy building materials and, if left unchecked, can weaken the building's structural integrity.
How does mold get started in buildings? Mold needs moisture, nutrients, and low-light conditions to get started and to continue to grow or amplify. The
moisture can come from flooding, leaking roofs and windows, leaking or broken pipes, and high humidity (greater than 60%) caused by faulty air conditioning
systems. Improper drainage and landscaping can also result in water intrusion. The food source can include organic building materials and cellulose. Mold
growth can occur in old and new buildings given the right conditions, and may be further aided by today's tightly sealed, energy efficient buildings that actually tend
to trap moisture and sometimes have inadequate ventilation. Indoor mold can grow hidden inside walls, behind wall coverings, baseboards, and under and on
carpeting. In certain situations, HVAC systems can actually circulate the mold's spores to other areas of a building, aiding its spread.
Given the critical requirement for moisture, is mold a problem in arid areas such as Arizona? Yes, in fact, both Arizona and Nevada now rank among the top eight
states having the most mold insurance claims. Texas and California are the leading states - with Farmers Insurance Group in Texas alone registering more than
12,000 mold claims in 2001, up from 12 in 1999 (Wall Street Journal, May 14, 2002). Litigation is on the increase too, with one Texas homeowner being
awarded $32 million in a "toxic mold" claim against his insurance company. These claims are troublesome because they often involve more than one type of claim
and could target builders, architects, HVAC equipment suppliers and installers, etc. According to a quote recently from Kevin DeSantis, an attorney with Butz,
Dunn, DeSantis & Bingham in San Diego, "We're seeing the typical residential construction defects case turn into a bodily injury claim, as a result of water
intrusion causing mold to grow in the interior of walls." Clearly, mold has now become a potentially serious concern for the building industry and allied professions.
© WTI, Inc. 2002
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