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MoldMolds are microscopic organisms that play an important role in the breakdown of plant and animal matter. Outdoors, molds can be found in shady, damp areas or places where leaves or other vegetation is decomposing. Indoor molds can grow on virtually any surface, as long as moisture, oxygen, and organic material are present. When molds are disturbed, they release tiny cells called spores into the surrounding air. Exposure to these spores can produce symptoms such as nasal and sinus congestion, eye irritation and blurred vision, sore throat, chronic cough, and skin rash. After contact with certain molds, Individuals with chronic respiratory disease may have difficulty breathing and people who are immunocompromised may be at increased risk for lung infection. A study conducted by NIEHS-funded scientists shows that mold exposure during the first year of life may increase the risk of childhood asthma.

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  • Asthma(
  • Children’s Health(
  • Lung Disease(

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Last Reviewed: June 02, 2008