How Bad Is Black Mold, Really?

Many people believe something called "black mold," or "toxic black mold," is a specific type of noxious mold that can severely sicken or even kill you because it releases noxious mycotoxins or mold poisons. But that's not totally accurate. First, molds of all colors can cause illness. And second, there are many types of black-colored molds. The one most people have in mind when they refer to black mold, or toxic black mold, is Stachybotrys chartarum (S. chartarum), a greenish-black mold.

Research published in Analytical and Bioanalytical Chemistry suggests S. chartarum may be linked to serious health problems such as mycotoxicosis, or mold poisoning. Other possible ill effects include body aches, headaches, memory loss, mood swings and nosebleeds. But the science isn't definitive. A 2017 report published in Clinical Reviews in Allergy & Immunology states, "There is no scientific evidence that exposure to visible black mold in apartments and buildings can lead to the vague and subjective symptoms of memory loss, inability to focus, fatigue, and headaches that were reported by people who erroneously believed that they were suffering from 'mycotoxicosis.' Similarly, a causal relationship between cases of infant pulmonary hemorrhage and exposure to 'black mold' has never been proven. Finally, there is no evidence of a link between autoimmune disease and mold exposure."

Experts say it's important to note that all types of mold may pose a health risk to certain people, especially if they are exposed to large quantities of it. Those most at risk for mold-related health issues are people with allergies, asthma, preexisting lung conditions and compromised immune systems; e.g., people undergoing cancer treatments or transplant patients. Infants, kids and older adults are also more at risk, as are people with certain chemical and genetic factors. However, there isn't a test that can determine a link between Stachybotrys chartarum and certain health symptoms, notes the Centers for Disease Control and Prevention.

Allergy sufferers who come into contact with mold may develop a runny nose, watery eyes, dry cough, skin rashes, sinusitis and other respiratory issues. Those with compromised immune systems or lung disease could develop fungal infections, while people with respiratory disease may have difficulty breathing. Some suffer for years.

Marie Sterling (not her real name) has been struggling with health issues for 14 years since coming in contact with mold. Despite seeing some of the nation's top mold doctors, her health has never been the same. "I am still permanently sick," she says. "Mold is the worst."

It's pretty easy to determine if you've got a mold problem in your home, because you will usually see or smell it. There's generally no need to do any kind of testing or sampling, according to the Environmental Protection Agency. And you typically don't need to hire someone to remove it, either, unless you've got a significant area covered in mold — say, larger than 10 square feet (3 square meters). For typical infestations, here's what to do.

Mold doesn't grow unless there is moisture. To keep mold from returning, fix any water leaks. Make sure your bathrooms, laundry room and kitchen are well ventilated. During humid summer months, use an air conditioner and dehumidifier. Don't carpet moisture-prone areas, such as bathrooms and the basement. Your home's humidity level should remain between 30 and 50 percent year-round. And check that your kitchen, bathroom and clothes dryer vents are all vented to the outside of your home.