There are three kinds of common mold that can appear black.

  1. Aspergillus niger, a genus (blanket term) for several individual types of mold that appear black and are most often seen on spoiled produce. For people with a healthy immune system, this genus of mold is a nuisance but not typically dangerous.
  2. Cladosporium is a family of molds that can appear as green to black and can be found indoors or outdoors. Again, for most people, this type of mold is not likely to cause serious illness.
  3. Stachybotry chartarum is the black mold that can cause the most health problems. It is the one that people refer to as “toxic black mold.” While it occurs outdoors in wood and dead leaves, it is found in homes and buildings because it thrives well in high cellulose materials like fiberboard, wood, drywall (aka gypsum board), and paper. Limited exposure to this mold typically won’t cause serious problems. From extended exposure to Stachybotry chartarum, people with suppressed immune systems can produce a strong allergic reaction or trigger illness that presents like pneumonia.

Detecting the Presence of Mold

  • Of course, the most obvious indicator of mold is the presence of dark spots in walls, ceilings, and floors.
  • However, when you walk into a building or individual room and you quickly smell a musty odor, this also is a strong indicator that there is a mold issue. When mold is hidden under flooring or carpets, this mold smell may actually be the primary indicator of the presence of mold.

Removing Black Mold

The good news is that black mold, like any other mold, can be eliminated from homes and buildings and its microbial growth can be prevented altogether.

  1. Mold Remediation is the process of removing mold from a building.
    1. Recommended Mold Treatments
      1. If the area that contains mold is less than ten square feet1 and the area does not contain natural stone, waxed wood, cast iron, or aluminum, you may be able to stop its growth by treating the area with full-strength distilled white vinegar2. Remember to wear protective equipment if you choose to do the clean up yourself.
      2. If the mold doesn’t resolve after treatment with vinegar or the area is greater than ten feet square, it is recommended that you contact a professional mold removal company. A professional will perform a mold test and provide you with a quote for the mold removal cost.
  2. Mold Abatement is the process of preventing mold from growing in the first place.
    1. Water mitigation/water cleanup: Anytime water has spilled or pooled in a house, it needs to be cleaned up and dried thoroughly and quickly. When water has intruded beyond surfaces, the help of a water mitigation specialist likely is required.
    2. Control the humidity in your rooms. The key to preventing mold from growing is to keep the building dry and well ventilated.3 Mold needs water to grow. It is important to find the sources of any leaks or spills and address them at the source. In spaces where water often flows and condenses on ceilings, walls, or floors such as in a bathroom, turning on a fan, turning on a heater, and keeping windows or doors cracked open will help keep moisture in the air from accumulating. Using a squeegee on shower walls and mopping up water outside the tub or shower after each use will also reduce the moisture in the room. One easy way of noting whether moisture is building up is to note whether windows and mirrors fog up during a shower or bath. If they are, you need to do more to assure that doesn’t continue to happen. You may need to upgrade your fan or windows for better ventilation.
    3. Periodically clean areas with distilled white vinegar. Keeping dust and debris out of crevices and corners will help keep moisture from staying in these spaces. The mild acidity of the white vinegar will kill mold spores before they have the chance to grow.4

References:

1 “Mold Cleanup in Your Home”. United States Environmental Protection Agency (EPA).
2 “A Guide to Cleaning Mold with Vinegar”. merry maids.
3 “Basic Facts about Mold and Dampness”, August 2020. Centers for Disease Control and Prevention.
4 How to Get Rid of Black Mold”. Home Depot.