Toxic Mold
A report by the National Academies of Sciences debunks the myth of "toxic mold," a myth that has spurred such headlining lawsuits as the 2001 $32 million verdict for homeowner Melinda Ballard, who claimed that mold in her home injured her family, and the 2003 $7 million settlement for TV personality Ed McMahon, who claimed the fungus killed his dog. A pair of reports released last summer by the Manhattan Institute and U.S. Chamber Institute for Legal Reform outline both the history of the mold panic and its legal implications (in an article written by attorneys) and the (lack of) science supporting "toxic mold" claims (in an article written by scientists).
Much of the mold panic was fueled by earlier U.S. Centers for Disease Control studies in 1994 and 1997 that initially found an association between exposure to stachybotrys chartarum mold and lung damage in a group of infants in Cleveland. In 2000, however, the CDC took the very unusual step of retracting its endorsement of the earlier reports, citing faulty methodology.
By that time, however, mold claims had been popularized by the media, and the CDC's retraction did little to stop the stories -- or the suits. The New York Times Magazine ran photos of workers in hazard suits combing through Ballard's mold-infested Texas mansion. The American Bar Association Journal headlined an article MOLD IS GOLD and predicted that mold could be bigger than asbestos. Law professors referred to "toxic mold" in academic papers, and consultants advertised their services claiming mold is "black gold." Through 2001, mold claims had added over $1 billion in annual costs to the homeowners-insurance system in Texas, or about $440 for every insured household.
The new NAS report, like the MI-ILR paper published last summer, finds that mold is an allergen that can cause wheezing, coughing, and the like among atopic (allergic) individuals; but also finds no link between mold and alleged more serious injuries attributed to it, and thus no scientific basis for claims of mold toxicity.
In another effort to address this misconception, in 2003, the National Association of Home Builders commissioned a review of available scientific literature. The commissioned panel included well credentialed experts from the fields of mycology, industrial hygiene, immunology and toxicology. The panel concluded that while evidence exists to support an association between exposure to indoor dampness and the occurrence or exacerbation of asthma or upper respiratory infections, there is insufficient evidence to support a causal relationship between exposure to mold in the indoor environment and any systemic disease or neurological illness. This study was largely ignored by the media and the plaintiff’s bar, either because they found the results uninteresting or discounted same as industry biased.
However, in May 2004, the Institute of Medicine, an organization affiliated with the National Academy of Sciences, issued a report that reached the same conclusions. The study concluded that exposure to excessive dampness and mold could cause upper respiratory problems in individuals sensitive to mold, but that no evidence existed to support claims of fatigue, neuropsychiatric disorders or similar serious disorders that some were claiming from exposure to mold in the indoor environment. This report simply cannot be ignored by any responsible party.
Despite recent mold hysteria, the building owners and managers should approach these claims with healthy skepticism. There are strong defenses to any mold claim, especially since mainstream scientists have found little reason to believe that naturally occurring mold can cause anything more than short-term allergic or irritant responses. Here are some important points to remember:
- Most lawsuits are based on the alleged effects of "mycotoxins," the by-products generated by so-called "toxic molds" with scary names such as Stachybotrys chartarum, Aspergillus, and Penicillium. But the dose of mycotoxins that would be necessary to cause toxic responses in humans is far higher than those mycotoxins ever occur in a real-world environment.
- The only known health effects of inhaled mold are allergic reactions (stuffy nose, watery eyes, wheezing) and exacerbation of pre-existing asthma. The U.S. Centers for Disease Control has found no proof of any causal link between mold and more serious health conditions such as pulmonary hemorrhage or memory loss.
- The CDC has also debunked much of the mythology of "toxic mold" by determining that the exact species of indoor mold has little correlation with the potential health effects. In other words, there are no "bad" molds, and only individualized testing can determine which molds can cause allergic effects in any given person.
- Mold is everywhere, and like most other substances that we inhale or ingest, our bodies metabolize and excrete it. Claims that mold has "built up" in one's body are based on a fundamental misunderstanding of human biology.
- Long-term health effects show that mold is not the cause, since the effects of mold exposure end shortly after the exposure ends.
Although long-term health effects have not been linked to mold exposure, mold should not be ignored. It is an allergen and an irritant, and usually is a tip-off of an underlying moisture problem that could cause structural damage, as well as being unsightly and often emitting an unpleasant odor.
To sum up this issue: Mold is everywhere. It's not toxic but it is a concern and should be addressed whenever encountered in a building.
