Mold and Your Health

People are exposed to molds every day, usually by touching or breathing them. Because molds naturally exist outdoors and indoors, living in a totally mold-free environment is practically impossible. As molds grow, spores can be released into the air where they can be easily inhaled. People who inhale large numbers of spores may get sick. Possible health concerns are an important reason to prevent mold growth and to clean up molds in indoor environments.

Many molds can cause health effects. Molds produce allergens, irritants and, sometimes, toxins that may cause adverse reactions in humans. A reaction to mold depends on how much a person is exposed to, the age of the person and the person’s sensitivities or allergies. The same amount of mold may cause health effects in one person, but not in another.

Exposure to mold can cause a variety of symptoms. Sensitive people who have touched or inhaled mold or mold spores may have allergic reactions such as a runny nose, sneezing, nasal congestion, watery eyes, skin rash and itching (dermatitis). Molds can trigger asthma attacks in people who are allergic to molds, causing wheezing, chest tightness and shortness of breath. A disease like pneumonia may also develop after exposure to mold, but this is uncommon.

Infectious diseases from molds can occur in people with weakened immune systems, such as those who are immune-compromised or immune-suppressed from drug treatment. Some types of mold are known to cause infections in immune-compromised people. Such infections can affect the skin, eyes, lungs or other organs. These are considered opportunistic infections that usually do not affect healthy people.

Another source of irritation from mold exposure comes from substances known as microbial volatile organic compounds (mVOCs). These compounds are produced through fungal metabolism and are released directly into the air, often giving off strong or unpleasant odors. Exposure to mVOCs from molds can irritate the eyes and respiratory system and has been linked to symptoms such as headaches, dizziness, fatigue, nasal irritation and nausea. The effects of mVOCs are not completely understood and research is still in the early stages.

Other metabolites, called mycotoxins, are potent substances produced by some molds. People can be exposed to mycotoxins through inhalation, ingestion or skin contact. Many molds, including species commonly found indoors, are capable of producing mycotoxins. The existence
or identification of a toxin-producing mold indoors does not mean that building occupants have been exposed to mycotoxins or that they are even present, since molds do not produce them under all conditions. Mycotoxins can cause a variety of adverse health effects, but more research is needed to determine the health risks posed by mycotoxins in indoor environments. However, it is clearly advisable to avoid exposure to mold and mycotoxins.

Some physicians have recommended testing for mold-specific antibodies. The presence of antibodies only indicates that you have been exposed to a substance at some time. It does not tell you when you were exposed, where the exposure took place, or how much of the mold you were exposed to. Having a positive test for mold-specific antibodies alone is generally considered insufficient to prove that health effects reported by individuals in moisture-damaged buildings are caused by exposure to mold.

There are medical tests to determine if you are allergic to a particular substance, such as mold. These can be performed on skin or blood. Skin tests are considered more reliable than blood tests to determine allergic reaction to a substance. Skin tests yield results more quickly, are less expensive than blood tests and are generally considered more sensitive. If an individual has symptoms year-round, which may indicate an indoor allergy, skin testing may be recommended.

Blood testing called the RAST (radioallergosorbent) test can be done to show if you are allergic to a substance. The RAST test detects levels of antibodies to particular allergens. The test is expensive to perform and results are usually not available for about two weeks.

People who know they have been exposed to mold and have symptoms that persist should consult their physicians for possible treatment and testing.

Illinois Department of Public Health
Division of Environmental Health
525 W. Jefferson Street
Springfield, IL 62761
217-782-5830
TTY (hearing impaired use only) 800-547-0466