When it Rains, it Molds

Part 1 of 2

By Marcia Anderson

Mold spores up close

Mold spores up close

When I went back home recently to visit my family, I noticed a number of mold spots on the ceiling in multiple rooms. A result of roof water damage from the winter ice and snow the northeast experienced this year. This prompted me to have an interview with Mark Berry, EPA’s Indoor Air Quality Coordinator for Region 6 (serving Arkansas, Louisiana, New Mexico, Oklahoma, Texas and 66 Tribes). Here are his responses to some common questions about mold and moisture.

  1. What is it that many people misunderstand about mold? It is important to view mold, not as a mold issue, but as a moisture issue. People think that mold is a hazardous material. Most people do not realize that mold and mold spores are all around us. Molds live in the soil, on plants, and on dead or decaying matter. Outdoors, molds play a key role in the breakdown of leaves, wood, and other plant debris. Molds produce tiny spores to reproduce, just as some plants produce seeds. These mold spores can be found in both indoor and outdoor air, and settled on indoor and outdoor surfaces. When mold spores land on a damp spot, they may begin growing. It is important not to provide the moist environment mold needs to grow.The solution to the problem is to find and eliminate the moisture source first, and not focus only on the mold. Removing the mold alone does not solve the problem. If the water remains, new mold will grow in the same area.
  1. Mold spreads in the damp area behind a sink

    Mold spreads in the damp area behind a sink

    Should I use bleach to clean up my mold? In most cases using bleach isn’t necessary. Soap and water will often do the trick. Using bleach or some other harsh chemical cleaners can create a breathing hazard for you. If you choose to use disinfectants or biocides, always follow manufacturer’s directions, ventilate the area and exhaust the air to the outdoors. Never mix chlorine bleach solution with other cleaning solutions or detergents that contain ammonia because toxic fumes could be produced.

  1. Can I just paint over the mold? Many people see mold, spray some chemical then paint over it, thinking that will solve the problem. Mold can grow between the paint and the wall in all directions. The paint merely acts as a temporary cover-up. The issue with the paint is that it traps moisture between the paint and the wall, further aiding and abetting the growth of mold. Fix the source of the moisture first, and then take the appropriate steps to clean the affected area or remove it altogether.
  1. What are your most compelling mold calls? Landlord /tenant disputes over mold are our most frequent calls. We attempt to educate and make suggestions for remediation that may be used or not used by the caller’s choice. Callers need to consider the problem as both a building water issue as opposed to a mold issue. This strategy addresses the cause of the mold infestation and not the symptom. We try to get to the root cause of the problem and ease the caller’s concerns. Mold is essentially the result of water damage.
  1. Is there more mold in different parts of the country? Yes, and No. We have more mold inquiries in humid areas because the mold continually gets fed more moisture which allows it to flourish. However, mold can grow everywhere and can exist in a broad range of temperatures and humidity levels. Although moisture is necessary for growth there are molds which prefer drier environments and would need much less than other types to survive.
  1. Mold can be a variety of colors

    Mold can be a variety of colors

    What are your most frequent calls? “I’ve got mold problems can you do something to help me?” EPA Region 6’s Indoor Air Quality program (IAQ) is a voluntary program primarily responsible for conducting outreach and educating the public about indoor environmental issues, including health risks and the means by which human exposures can be reduced. IAQ educates the public about indoor environmental pollutants and sources of pollution, including mold. However, EPA does not have any regulatory authority to control mold in private residences nor do we have the resources to inspect individual homes.

    The EPA does not conduct mold cleanups, but we do provide the education necessary to give people the strategy and empowerment needed to solve the problem. We recognize the health danger to schools, homes and places of work. The EPA is the technical lead in mold research from which many states and local agencies borrow.

  1. Is testing for mold necessary?
    In most cases, if visible mold is present, sampling is not necessary. Since no EPA or other federal limits have been set for mold or mold spores, sampling cannot be used to check a building’s compliance with federal mold standards. Remember that mold and mold spores are natural in the environment so any sampling will result in finding mold.

For more information on controlling mold and moisture, visit www.epa.gov/mold

About the Author: Marcia is with EPA’s Center of Expertise for School IPM in Dallas, Texas. She holds a PhD in Environmental Management from Montclair State University along with degrees in Biology, Environmental Design, Landscape Architecture, and Instruction and Curriculum. Marcia was formerly with the EPA Region 2 Pesticides Program and has been a professor of Earth and Environmental Studies, Geology, and Oceanography at several universities.

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