The Michigan Association of REALTORS® provides this FAQ guide as a consumer service for informational purposes only. For specific questions, ask your REALTOR® or a health official.

Q: What is mold?

Molds are found everywhere, and occur naturally, serving a useful purpose in breaking down and decomposing organic matter. They are microbial organisms, which reproduce and spread by emitting spores into the air, which land on other surfaces and generate additional mold. Mold growing in indoor environments has been suspected of causing adverse health effects.

Q: What types of mold found in indoor environments

Molds found indoors grow as a result of the presence of moisture inside indoor environments, and can also enter from outdoors through doors, windows and ventilation systems. When mold spores attach to an area of excessive moisture (e.g from a leaky roof or wall system), many cellulose-based building materials provide nutrients for mold growth (such as ceiling tiles, paper-backed sheet rock, insulation materials, and wood/wood products).

The most common types of mold indoors include:

• Aspergillus and its subspecies (A. flavus, A. versicolor);
• Cladosporium;
• Penicillium;
• Alternaria; and
• Stachybotrys atra (“S. atra”), also known as stachybotrys chartarum, a greenish black mold commonly referred to as “Black Mold.”

Q: What are the possible health effects from mold exposure

Often, mold spores, whether dead or alive, have been suspected in causing adverse health effects, primarily of a respiratory nature, including hay fever-like allergic symptoms. =The molds may also adversely affect persons with pre-existing respiratory illnesses, such as asthma and chronic obstructive pulmonary disorder.

Many of these molds, primarily S. atra, also produce chemical toxins known as “mycotoxins,” which are generated and released into the air within the molds spores, perhaps leasing to the “toxic mold” designation. Exposure to these toxins can occur through inhalation, ingestion, or skin contact, and can result in symptoms including dermatitis, cough, rhinitis, nose bleeds, cold and flu symptoms, headache, general malaise, and fever.

Initial awareness of adverse health effects from S. atra exposure was raised by a mid-90s study from Cleveland, Ohio, revealing infants who had dies from sudden and unexplained pulmonary hemorrhage (bleeding of the lungs). Upon investigation, researchers found that the infants resided in homes with high levels of S. atra, as well as tobacco smoke, leading to a possible hypothesis linking S. atra exposure to serious health effects, in addition to mere allergy-like symptoms. However, the Centers for Disease Control has noted that further studies are needed to determine the causes of unexplained acute hemorrhage. These studies have now been authorized by the U.S. Environmental Protection Agency (“EPA”) and will evaluate mold growth, emission of mold spores, and mold’s impact on indoor air quality.

Q: What kind of mold testing is available?

At the present time, no official standards or guidelines exist to determine acceptable or unacceptable limits for mold in the indoor environment.

Nevertheless, a cottage industry of mold testing companies, consultants, and remediators has sprung up to meet public demand for mold response services. The U.S. EPA has developed a new test using DNA technology, which can rapidly identify and quantify 50 to 100 common indoor mold types in a matter of hours, including S. atra. The EPA’s test has been licensed for use by private companies, at costs ranging from $30.00 to $50.00 per test. Numerous Michigan firms and consultants now offer mold testing and analysis services. Testing can also include air sampling, which involves obtaining and culturing air samples for microbiological growth, followed by microscopic examination after incubation.

Q: What is mold remediation

In general, the first and critical priority in indoor mold remediation is to identify and correct the moisture source before beginning remediation, since mold can recur if moisture returns or water penetration is not stopped. Homeowners can clean up small areas of surface mold on their own, by drying and disinfecting the areas with a bleach solution, and disposing of any moldy porous materials such as carpet or sheetrock. A licensed contractor or professional is advised for large jobs, or where a homeowner’s health becomes adversely affected while attempting remediation work. In some recent cases, including cases in Michigan, mold growth has become so extensive as to require demolition of the home, rather than remediation.

As in the case of mold testing, no recognized federal or state guidelines exist to govern remediation efforts. The New York City Department of Public Health has promulgated guidelines for assessment and remediation of indoor mold and fungi which appear to be the only published remediation standards currently in existence.

Depending on the amount of mold contamination observed on visual inspection, remediation proposed by the New York guidelines can range from simple clean-ups performed by custodial or maintenance staff to full-blown clean-ups involving airlocks, decontamination suits and respiratory protection similar to asbestos abatement activities. It remains to be seen whether the New York guidelines are adopted as a model by the EPA or state regulatory agencies. In any event, implementation of these guidelines would entail substantial expense in all but the most minor mold growth situation, due to the guidelines’ requirements for trained personnel and protective equipment. Mold remediation generally is also expensive, for the reason that demolition and replacement of portion of a structure are usually required (e.g. walls, wall cavities, roof decking, flooring, and any other building material contaminated with mold).