Yet over the past decade, the fungus has become the subject of high-profile lawsuits, filed by such celebrities as Ed McMahon and crusading paralegal Erin Brokavich. It also has been the inspiration for two academies where devotees learn about molds of all kinds, and it has become widely regarded as one of the more urgent environmental health threats facing Americans.
Mold's current prominent status belies its extremely ordinary and largely benign place in the planet's ecosystem. Composing approximately 25 percent of Earth's biomass, fungi decompose organic matter and provide plants with nutritional elements. However, since the mid-1990s, lawsuits and health experts have claimed "toxic mold" causes a laundry list of illnesses from Alzheimer's disease to cancer. As a consequence, mold has moved from harmless helper to dangerous villain.
How did this mold frenzy take hold and what do we really know about its health effects?
"When it comes to allegations of all sorts of health effects being attributed to mycotoxins (mold toxins), the toxicology does not support that as being reasonable or feasible," Bryan Hardin, with Globaltox, a toxicology consulting group in Redmond, Wash., told United Press International.
Despite minimal scientific evidence behind many of these health claims, mold exposure litigation is skyrocketing, with over 10,000 cases currently pending.
In 1994, Cleveland health officials noticed an unusual cluster of infant deaths caused by a rare infection of the lungs. The Centers for Disease Control and Prevention in Atlanta investigated the outbreak and concluded the deaths might be linked to exposure to stachybotrys mold, later called toxic mold, in the infants' homes.
The finding set off widespread panic and reports of a "killer fungus" dominated television newscasts.
The CDC has since discounted stachybotrys as the culprit in the Cleveland deaths but the mold scare already had taken hold and acquired a life of its own.
"The reports from Cleveland and other studies that purport to show a link between mold and infections have serious methodological flaws and they cannot be relied upon to show an association," said Hardin, who co-authored a review of the scientific research on the subject for the American College of Occupational and Environmental Medicine in Arlington Heights, Ill.
Then in 1999, in an unprecedented verdict, a Texas jury awarded a Dripping Springs family $32 million in punitive damages and compensation for their mold-infested home. The plaintiffs alleged stachybotrys mold exposure had caused one family member brain damage -- a claim that eventually was thrown out by the judge due to lack of evidence. Nonetheless, the verdict reflected the jury's conclusion that mold had caused the family's health problems.
"In the original suit the plaintiffs said, 'I have mold in my house and my husband has brain damage' and that was enough. The jury decided to punish the insurance company," David Warner, spokesman for the U.S. Chamber of Commerce which opposes the recent boon in mold litigation, told UPI.
Indeed, the Texas verdict touched off a flurry of similar lawsuits and since 1999, mold litigation has increased by 300 percent. Most of theses legal actions have targeted the insurance industry, which has been forced to hike premiums in some states in order to shoulder the financial burden.
"There's hardly a history of mold litigation issues for us because it hasn't been a real problem until three years ago (with the Texas lawsuit) and then suddenly it's a billion dollar problem," Carolyn Gorman, vice-president of the Insurance Information Institute in New York City, told UPI.
Although the insurance industry remains hopeful mold lawsuits are on the wane, the Trial Lawyers of America has made quite a different prediction. On its Web site, the TLA notes toxic mold litigation still is on the rise nationally and likely will surpass asbestos in terms of case volume and value.
The TLA's interest in mold lawsuits rests on the notion that serious health consequences can be linked to indoor exposure, Gorman said. Million-dollar lawsuits would not be pursued if the complaints centered on allergy irritation or simply building damage, she added.
Studies done on mold's health effects suggest it can irritate pre-existing conditions such as asthma and allergies. In very rare cases -- usually when a patient is severely immunocompromised -- fungi can cause serious infections.
"If you live in a moldy house and you have asthma, your asthma is likely to get worse - That's well documented," Harriet Burge, Harvard University public health professor and mold expert, told UPI. "If children are born into damp houses they tend to have more respiratory infections over their childhood than if they lived in a dry house," she said.
For that reason, the CDC, the U.S. Chamber of Commerce and ACOEM advise people with mold problems to identify the water source causing its growth and clean up existing infestation with either bleach or soap and water.
An association between airborne exposure to any mold and cancer has never been documented nor has a link been shown between mold exposure and neurological damage, Burge noted.
In fact, by blaming mold, we could be missing another important culprit behind the illnesses of plaintiff's who claim they have suffered health problems due to indoor exposure. The symptoms of mold patients are astonishingly diverse - from ear aches to memory loss - which is another sign that their condition is not caused by an environmental exposure, Burge said.
"If you had a toxin in the environment you would have the same symptoms not a wide range like this. And if it isn't mold, then what is it? If it's a serious problem, I'd hate to see these people getting worse just because they're convinced it's the mold," she said.
Only a limited number of studies provides suggestive evidence mold exposure might cause more serious symptoms. A study by Veteran Affairs Northern California Health Care System found patients who were exposed to mold in their homes and workplaces performed worse on a number of cognitive measures than unexposed subjects.
A sentinel study by Dr. Eckardt Johanning of Albany, N.Y., reviewed the symptoms and tested blood samples of patients with indoor mold exposure and found they exhibited disorders of the respiratory system, skin, mucous membranes, and central nervous system. However, because the researchers did not compare the subjects to an unexposed control group, the findings are of limited use. The researchers also noted although all of the subjects were exposed to indoor mold, less than 25 percent of them showed fungi-specific antibodies in their blood samples.
Given this very limited evidence of adverse health effects associated with mold exposure, at this point it is safe to say mold growth is unsightly and can damage buildings -- but it will not kill you, Burge explained.
After all, mold has been all around us, both indoors and outdoors, since prehistoric times. People with allergies and asthma should limit their exposure when possible but the rest of us might be better off just making peace with the mold in our lives, Hardin said.
"Mold is something that's part of the natural world," he added. "It's everywhere and it's unavoidable."