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How does toxic mold make you sick?


Toxic Mold in Your Home
Former Tonight Show co-host Ed McMahon was awarded $7.2 million in damages from home contractors for failing to properly clean up toxic mold from his home following water damage. McMahon and his wife both fell ill from the mold infestation, and their dog Muffin died.
Former Tonight Show co-host Ed McMahon was awarded $7.2 million in damages from home contractors for failing to properly clean up toxic mold from his home following water damage. McMahon and his wife both fell ill from the mold infestation, and their dog Muffin died.
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Mold can enter your home through a variety of ways. It can come in through an open window, your air conditioning system, a vent, or even attach itself to your clothing or pet. And once mold gets inside, it's difficult to get rid of entirely. Fungus spores may lie dormant in your home until they come in contact with the right conditions for their growth.

S. chartarum thrives in damp environments with a relative humidity of around 94 percent [source: EPA]. The need for this much humidity would logically cut down on the possibility of a toxic mold infestation, since most houses feature a much lower relative humidity than that. But a leaky roof, plumbing or even a damp flower pot can provide the humidity needed for S. chartarum and other toxic molds to grow.

Toxic mold prefers cellulosic materials, such as gypsum board and fiberboard. Wet building materials provide a perfect habitat for S. chartarum. Drywall and carpet damaged by flooding or broken water pipes can become colonized, and pose enough of a health risk that the CDC advises these materials be carefully removed and thrown away [source: CDC].

To examine under which conditions and on what surfaces chartarum grows best, the Environmental Protection Agency created a chamber to simulate different indoor climates. The EPA studied building materials commonly found in homes, like drywall and ceiling tiles. They also used these chambers to test antimicrobials -- agents like fungicides -- to find which works best in killing S. chartarum. While these experiments are not yet concluded, the EPA says its aim is to quantify the health effects of molds like S. chartarum on humans. In other words, the EPA seeks to find out how much mold is acceptable and how much, if any, poses a health threat.

In the meantime, agencies like the CDC recommend that all mold infestations be treated in the same way -- carefully. One of the reasons for this is because S. chartarum may colonize along with groups of other, less dangerous molds, and can be difficult to detect. And since almost all molds can cause allergies in some people, don't bother having samples taken of the mold you find in your home, says the CDC, just get rid of it.

If your home has suffered water damage from a broken water pipe or a flood, it's a good time to check for mold growth. Mold can grow and spread in as little as 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. Wear a dust mask, rubber gloves and long sleeves and pants while you clean up a mold infestation.

Materials like carpet, ceiling tiles, pillows, insulation and drywall should be thrown away since they are absorbent and won't respond to cleaning. Hard surfaces like concrete floors, ceramic tiles and Formica countertops can be cleaned of mold. While the EPA continues its investigation into the best antimicrobial to kill toxic mold, the CDC suggests that you use a solution of no more than one cup bleach to one gallon water to kill mold (never mix ammonia with bleach, by the way).

After cleaning, make sure you've removed all of the mold; you can still get sick from dead mold left behind. And ensure that you've dried the formerly infested area well to keep spores from coming back. But you don't have to wait for a flood to kick mold out of your house. You can also fight mold every day by taking some simple steps like using your air conditioner during humid months and cleaning the drain pan beneath your refrigerator once a month.

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