Mold grows anywhere there is water, and homes that sustain flood damage are likely to face substantial mold remediation issues. One type of mold commonly present where homes have been water damaged is Stachybotrys chartarum.

What is black mold (Stachybotrys chartarum)?

Black mold is the common name for the fungal genus Stachybotrys, species chartarum. Stachybotrys chartarum is also known as Stachybotrys atra. It is a greenish-black mold that needs moisture to grow. If airborne black mold spores land on a wet, porous surface, they will grow and release more spores. Black mold can grow in your home after water damage occurs, such as excessive humidity, water leaks, condensation, water infiltration, or flooding. It’s a greenish-black mold that grows on fiberboard, gypsum board and other materials used in home construction.

Is black mold “toxic”?

The spores that molds release for reproduction have the potential to cause health issues. Mold spores can act as allergens, causing allergic reactions. In addition to spores, some molds produce mycotoxins (myco- is a prefix that means fungal). Mycotoxins cause a toxic response in humans and animals, even in small amounts. There are over 400 known mycotoxins and almost all of them suppress the immune system. S. chartarum (black mold) is a mold that creates and releases mycotoxins.

The suppression of your immune system increases your risk of acquiring an infectious disease and reduces your body’s ability to fend off other contaminants. There is also evidence that mycotoxins can make you more susceptible to cancer. Symptoms that S. chartarum can cause include headache, cough, runny nose and can trigger asthma symptoms. It has also been connected to asthma in children exposed at schools.

Where does black mold grow?

Black mold grows on materials with high cellulose and low nitrogen content, including paper, dust, and lint. This includes some materials used in home construction, such as:

• Fiberboard: a building product made of wood and other plant materials often used as a replacement for traditional, solid wood to make furniture

• Gypsum board (drywall): used in most buildings for walls, ceilings and partitions

How to prevent black mold growth

The best way to control mold growth is to control moisture. The mold spores will not grow if moisture is not present. Indoor mold growth can and should be prevented or controlled by controlling moisture indoors. Begin cleaning up and drying out your home as soon as possible, ideally within 24 - 48 hours.

How to clean up black mold after a flood

1. Remove the moisture source. If moisture returns, the mold probably will too.

2. If the water damage is confined to one area of your home, seal doorways or other openings. You can seal them by duct-taping heavy plastic to all edges.

3. Place an exhaust fan in any openings to the outdoors.

4. Use soap and a sponge to remove visible mold.

5. If any moldy areas are dry, lightly spray a water mist on them. This will prevent you from sending mold spores into the air during cleaning.

6. If you use bleach, make sure it won't cause discoloration. Never mix bleach with ammonia. It will create toxic fumes.

7. Put all materials used in cleaning in a heavy duty garbage bag and seal it. Take the bag outside through the closest exit. You don’t want any spores to become airborne.

Ways to protect yourself from black mold

1. Wear respiratory (nose and mouth) protection when handling moldy materials.

2. Wear clothing that covers your arms and legs to avoid contact with mold spores. Wash or discard the clothing after every cleaning.

3. Wear gloves and protective eyewear.

4. Using a high-performance HEPA mold air purifier can help clean the air, even as work progresses. For example, the IQAir HealthPro Plus can dramatically reduce airborne particulates including mold, and can also reduce or eliminate any musty odors.

The United States Environmental Protection Agency (EPA) notes that although Indoor Air Quality may not seem like the most important problem during flood cleanup, standing water and wet materials are a breeding ground for viruses, bacteria and mold. Ensure your health safety by making it a priority. For more details and advice on dealing with mold and flood cleanup, visit epa.gov/mold.