How can toxic mold make you sick?

In January 1993, an infant in Cleveland, Ohio, became the first of 27 children to experience acute pulmonary hemorrhage. The infants bled from their airways, with their lungs infected by an unknown illness. One child tragically died. Investigations into the outbreak revealed that all the affected homes had significant water damage, and within these homes, the toxic mold Stachybotrys chartarum (S. chartarum) was found. It was determined that toxic mold was likely responsible for the children's illnesses.

The Cuyahoga County coroner revisited the deaths of infants in the area from 1993 to 1995, including those believed to have died from SIDS (sudden infant death syndrome). Six of these infants showed signs of pulmonary hemorrhage in their lung tissue. Though it's still unproven that mold caused the deaths, the question remains significant enough to prompt health experts worldwide to question just how dangerous this mold problem could be if it is indeed a health threat.

While the term 'toxic mold' is eye-catching and alarming, it's not the mold itself that is harmful—it's the spores the fungi generate. Mold species like S. chartarum, Fusarium, and Trichoderma release spores containing harmful substances known as mycotoxins. When these spores become airborne, they can be inhaled, absorbed through the skin, or ingested. Additionally, these molds emit gases that release further mycotoxins.

It is believed that these toxic spores can lead to skin irritation, lung inflammation, and may even suppress the body's immune system. Some have also attributed memory loss and brain damage to toxic mold, although medical science has not yet conclusively proven this link, despite a court ruling in favor of such a claim [source: White].

Mycotoxins may harm human health through cytotoxicity, as the spores destroy living cells to reduce competition for resources. This means that toxic spores, such as those produced by S. chartarum, can attack your body's cells, leading to a range of potential health issues.

There is no conclusive evidence yet that spores from mold like S. chartarum and other types pose significant health risks to people. While mycotoxins are known to have cytotoxic properties and cause harm to living tissues in laboratory settings, research on their effects on human health is still in its early stages. However, studying mycotoxins has become an urgent priority.

In response to the deaths of infants in Cleveland in the early 1990s, organizations such as the Centers for Disease Control and Prevention and the Environmental Protection Agency have started gathering evidence and developing databases to understand and combat toxic mold. Learn how to protect your home from mold, both toxic and non-toxic, on the next page.

Toxic Mold in Your Home

Mold can infiltrate your home in numerous ways. It might enter through an open window, air conditioning system, vent, or even attach itself to your clothing or pet. Once mold has found its way inside, it becomes hard to completely eradicate. The spores can lie dormant in your home until conditions become favorable for their growth.

S. chartarum thrives in damp environments where the relative humidity is about 94 percent [source: EPA]. While such high humidity levels are not common in most homes, a leaking roof, plumbing issues, or even a damp flower pot can create the necessary conditions for this toxic mold and others to grow.

Toxic mold favors cellulosic materials like gypsum board and fiberboard. Wet building materials offer an ideal environment for S. chartarum. Drywall and carpet damaged by flooding or broken water pipes are particularly susceptible, posing a health risk so significant that the CDC recommends removing and discarding such materials carefully [source: CDC].

To better understand the conditions and surfaces where S. chartarum grows best, the Environmental Protection Agency created a chamber designed to simulate various indoor climates. The EPA tested common building materials like drywall and ceiling tiles, as well as antimicrobials such as fungicides, to identify the most effective treatments for killing S. chartarum. While the studies are ongoing, the EPA's ultimate goal is to assess the health effects of molds like S. chartarum on humans, including determining what amount of mold, if any, is hazardous to health.

In the meantime, organizations like the CDC advise handling all mold infestations with caution. This is because S. chartarum can grow alongside other, less harmful molds, making it hard to detect. Since nearly all molds can trigger allergies in some individuals, the CDC recommends skipping mold sampling and simply removing it from your home.

If your home has experienced water damage from a burst pipe or flood, it's important to check for mold growth. Mold can begin to grow and spread within just 24 hours on materials like drywall and wallpaper under the right conditions [source: Clean Air Council]. If you find any, it's time to clean. Be sure to wear a dust mask, rubber gloves, and long sleeves and pants while cleaning up the mold.

Absorbent materials such as carpet, ceiling tiles, pillows, insulation, and drywall should be discarded, as they cannot be effectively cleaned. On the other hand, hard surfaces like concrete floors, ceramic tiles, and Formica countertops can be cleaned of mold. While the EPA continues to research the best antimicrobial treatments for toxic mold, the CDC recommends using a bleach solution with no more than one cup of bleach per gallon of water to eliminate mold (and never mix ammonia with bleach).

After cleaning, make sure all mold has been removed, as even dead mold can make you sick. Also, ensure that the previously contaminated area is thoroughly dried to prevent spores from returning. However, you don't have to wait for a flood to combat mold. You can take preventive measures daily, such as using your air conditioner during humid months and cleaning the drain pan under your refrigerator once a month.

For more information on mold and other related topics, visit the next page.