Molds in the Environment

What is mold?

A mold is a microscopic fungus that grows and lives on plant or animal matter or on nonorganic objects. Most molds are made up of filaments and reproduce through the production of spores, which spread by air, water, or insects. There are many thousands of species of fungi. Common indoor molds include:

  • Alternaria

  • Aspergillus

  • Cladosporium

  • Mucor

  • Penicillium

Molds are found everywhere in the environment, both indoors and outdoors, and throughout the year.

What are common reactions to mold?

Molds cause allergic symptoms in many people. Common reactions to molds include nasal stuffiness, eye irritation, or wheezing when breathing.

More severe reactions may occur among workers, such as farmers, who are exposed to large amounts of molds in occupational settings, including fever or shortness of breath. Mold infections may occur in the lungs of people with obstructive lung disease.

How can mold exposure be decreased?

  • Outside, avoid areas that are likely to have mold, such as:

    • Compost piles

    • Cut grass

    • Wooded areas

    • Damp, mossy areas

    • Greenhouses

    • Antique shops

  • Inside:

    • Keep humidity levels between 40 and 60 percent

    • Ventilate showers and cooking areas with exhaust fans

    • Use an air conditioner or a dehumidifier during humid months

    • Do not use carpet in susceptible areas, such as bathrooms or basements

    • Dispose of, or thoroughly dry and clean, objects, such as carpets or upholstery, that accidentally become wet

    • Fix leaks in roofs, walls, and/or plumbing to eliminate moisture

    • Add a mold inhibitor to paint when painting

    • Use mold-killing products to clean bathrooms

According to the Federal Emergency Management Agency (FEMA), mold is one of the most serious results of water damage from a hurricane or severe floods. Mold can grow within 24 to 48 hours after water damage and continue until proper measures are applied to stop it. The CDC states molds can be recognized from sight, wall or ceiling discoloration, and a bad odor or musty smell.

FEMA and CDC warn that returning to water-damaged homes after a disaster may pose serious health threats, especially to people who already have preexisting respiratory conditions, pregnant women, children, elderly, and people with immunocompromised diseases.

FEMA and CDC have developed specific guidelines for cleanup of water-related disasters. Please consult your doctor with any questions or concerns you may have regarding this condition.