What Are Molds?

Molds are a leading cause of poor indoor air quality in the homes of most residents in the U.S. Molds are small, microscopic organisms found both indoors and outdoors. They have tiny, light spores that travel through the air throughout buildings. In order for molds to grow, the spores need moisture, warmth, still air and food source. They land on moist surfaces of food, plants, dry leaves, etc. and multiply. Molds can be white, orange, green, brown or black and they have an earthy or musty odor.

Where Do Molds Grow in the Home?

Mold is most likely to grow in poorly ventilated and damp places indoors such as:

  • Showers / bathrooms
  • Damp basements
  • Backed-up sewers
  • Leaky roofs
  • Humidifiers
  • Constant plumbing leaks
  • Wet wood
  • Ceiling tiles
  • Wallpaper

Where Do Molds Grow in the Schools?

  • Roof and plumbing leaks
  • Condensation
  • Excess humidity
  • Tightly sealed buildings that do not allow moisture to escape
  • Delayed maintenance

How Do We Get Exposed to Molds?

When moldy material becomes disturbed, the spores can be released into the air and exposure can occur through:

  • Inhalation
  • Direct handling of mold-containing material
  • Ingestion of contaminated food

What Health Effects Do Molds Have on Us?

Molds can cause some people to develop an allergic reaction and / or asthma.

The signs and symptoms of allergies to airborne molds include:

  • Sneezing, with runny or clogged nose
  • Dry, hacking cough
  • Eye problems such as itchy eyes, burning, watery, blurred vision, inflammation of the eye lids and dark circles around the eyes
  • Itchy nose and throat, sore throat
  • Respiratory problems such as wheezing and difficulty breathing (in children with asthma)
  • Asthma

Who are at Risk from Mold Exposure?

  • Asthmatics
  • Individuals with allergies
  • Newborns, children
  • Elderly

What Do I Do About Mold in the Home?

  • Eliminate moisture from inside and outside sources as soon as identified
  • Clean all surfaces where there is mold with bleach and water mixture (1.5 cups of bleach to 1 gallon of water)
  • Change furnace and air conditioner filters regularly to prevent clogging
  • Repair all sources of roof leaks, plumbing leaks or flood damage
  • Remove or dry water-soaked materials such as ceiling tile, carpet and sheet rock

What Do I Do About Molds In The Schools?

  • Provide adequate ventilation
  • Inspect buildings for signs of molds such as around sinks, bathrooms, ceiling and walls
  • Clean and dry any damp or wet building materials
  • Prevent moisture condensation on windows, floors or roofs by adding insulation
  • Clean floors and carpets regularly

October 2008.

If you have any further questions, please contact your PEHSU at 1-866-MACCHE1 (622-2431)

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The information on this website should not be taken as medical advice, which can only be given to you by your personal health care professional.

"The development of this material was supported in part by funds from the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) trust fund through a cooperative agreement with the Agency for Toxic Substances and Disease Registry, Public Health Service, U.S. Department of Health and Human Services."

These web pages were supported by the Association of Occupational and Environmental Clinics (AOEC) and funded (in part) by the cooperative agreement award number 1U61TS000118-05 from the Agency for Toxic Substances and Disease Registry (ATSDR).

Acknowledgement: The U.S. Environmental Protection Agency (EPA) supports the PEHSU by providing funds to ATSDR under Inter-Agency Agreement number DW-75-92301301-0. Neither EPA nor ATSDR endorse the purchase of any commercial products or services mentioned in PEHSU publications.

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