Structural Mold versus Health Risks

Mankind has lived with mold for eons of time ... most of the time without adverse affects. So, why are people now becoming so agitated by the presence of mold in homes, schools and places of business?

The answer actually has several facets.

It is generally true that mold and people have peacefully coexisted for a long time. This is primarily because, historically, dwellings and congregational structures were well ventilated, which enabled rapid drying of the structure by air currents when they were impacted by rain, flooding, etc. Consequently, mold was less able to grow and thrive indoors. But, when it did colonize the structure, airborne mold spores were also readily carried out of the structure, preventing them from accumulating, thus reducing the risk of a chronic exposure to the residents.

People have long known, however, about problems associated with mold. About 4000 years ago the Old Testament (Vayikra /Leviticus 14:43-45) provided the cleaning procedure for homes infested with mildew (a type of mold) or leprosy. It is also known that during the middle ages, when people ate mold infested grains, they became violently ill.

Within the past several years, scientists have studied mold more intensely, and have learned that many of the human diseases previously attributed to bacteria and viruses are actually caused by fungi, which includes the molds and yeasts. There are more than 200,000 thousand species of fungi, with many more being rapidly discovered and classified daily. Mildew, a nicer sounding word than mold, is simply a particular kind of mold, but is no less ominous.

In particular, recent scientific studies have indicated that environmental exposure to mold and its spores can cause several severe clinical conditions. These human diseases can be generally categorized into three groups: allergenic (impacting the immune system); pathogenic (infecting living tissues); and toxic (poisoning).

Molds are well known agents of immune system dysfunction, including the initiation and exacerbation of allergies and asthma, as well as interfering with the normal immune response to foreign substances and organisms. Allergenicity is the primary disease associated with mold exposure.

Molds are also well known plant pathogens. However, there are only a relatively few fungi (less than a hundred) that are infectious to humans, where infections of the skin and internal organs usually occur in immunocompromised (improperly functioning immune system) people. Consequently, the pathogenicity of mold is far less prominent than its allergenicity in the human population.

Although the media and recent legal decisions have glamorized the notion that mold is highly toxic, this aspect of mold is by far less significant than allergenicity and pathogenicity.

Since late 1993, when an unusual outbreak in Cleveland, Ohio, of pulmonary hemorrhage in infants was linked to a black mold (Stachybotrys) in their homes, the medical community has focused much attention on the ability of mold to poison people not by ingestion (eating), but by simply being exposed to mold environmentally, and especially in residential settings.

While it is true that a handful of mold species produce mycotoxins (poisons), which are among the most potent poisons known to man, the concentrations of such toxins in the cells and spores of molds are extremely small. Consequently, a massive airborne exposure to such molds is necessary to provide a dosage sufficient to cause environmental poisoning. Although scientific literature has tended to vacillate over whether residential exposures to mold could provide a sufficiently massive dose to cause poisoning, recent data indicate that such exposures are not likely. Indeed, epidemiological data indicate that such massive environmental exposures are far more likely due to industrial (laboratory) contamination, agricultural infestation (involving direct contact with infested crops) and germ warfare.

Thus, despite the media hype, the issue of human exposure to toxic molds (commonly but mistakenly referred to as black mold) in homes, schools and places of business is of relatively minor concern.