Some molds are worse than others, said Tom Kelly, a director of the indoor environments division at the federal Environmental Protection Agency.
"There are a relatively small number of mold species that have been identified as producing a kind of toxin called mycotoxin," Kelly said. "What's not clear is whether they are toxic to human beings."
Some industry experts say there's growing evidence that they may be.
"We certainly are beginning to see strong indications that the so-called toxic mold can make you very ill," Hamilton said.
Whether some molds are more dangerous than others is just one of the questions researchers like Dr. David Zhang, a research biologist at New York's Mt. Sinai Medical Center, are trying to answer. There are more than 100,000 mold species, and about 50 are considered toxic. He has invented a DNA-based technology that spotlights the bad ones.
Scientists and doctors do agree on one thing: about one in three people can have allergic reactions to mold. For asthma sufferers who are very young, like Caitlin, or elderly, mold can trigger much more serious problems.
Destroying Home Values
The fungus can affect more than just health. Dan Sitomer, an attorney specializing in mold litigation, says it could destroy the value of your home.
"For the moment in time that that building is viewed as a problem its value goes to zero," Sitomer said. "The litigation is so aggressive and has multiplied so quickly that it has frightened the insurance industry. The damages can include almost anything. Pain and suffering, negligence, the claims go on and on."
Most insurance policies do not cover damages related to mold, according to Gordon Stewart, president of the Insurance Information Institute.
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