Indoor Molds


Fate and Transport in the Environment

Methods for Monitoring in the Environment

Exposure Pathways

Methods for Measuring Human Exposure

Strategies for Preventing or Controlling Mold Exposure

Harmful Effects

Absorption, distribution, metabolism, and sites of toxicity


Molecular mechanism of action

Risk Assessment

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Exposure pathway(s) of molds

Molds are present in nearly all environments. Humans are primarily exposed to these molds through inhalation. Fungal spores can remain in air for varying lengths of time allowing them to enter the respiratory system when inhaled. (Photo: Mold growing on a piece of ceiling tile)

Exposure can also occur through ingestion. Mold spores can be present on foods that are eaten. Spores are also ingested through hand-to-mouth contact of moldy surfaces.

Once the spores enter the host whether inhaled or ingested, they go through various physiological processes. Some of these processes form toxins to the human body called mycotoxins. Health effects include respiratory sensitization, asthma, asthma exacerbation, and stomach ailments. Studies have found that the elderly, children and immuno-compromised individuals are more susceptible to the side effects of mold exposure.


Levy, Barry S.; Wegman, David H. Occupational Health: Recognizing & Preventing Work-Related Disease & Injury, 4th Edition; Lippincott Williams & Wilkins 2000.

Mold and Human Health. 9/29/03

Children’s Environmental Health Network – Indoor Mold Fact Sheet. 9/29/03