Mold has become a common complaint throughout the county and nation. Molds are fungi that can be found both indoors and outdoors. No one knows how many species of fungi exist, but estimates range from tens of thousands to perhaps three hundred thousand
or more . It is common to have small mold growth in areas with high humidity such as bathrooms, showers/baths, and kitchens. Most of the time, mold problems can be
solved by finding and stopping the cause of moisture in the affected area, then cleaning the area with a common disinfectant (Lysol, bleach water, etc.).
More information regarding mold can be found at the Centers for Disease Control and Prevention and Environmental Protection Agency websites.
Mold Growth in the Home
Mold spores are regularly found in indoor air and on surfaces and materials -- no indoor space is free of them. However, when an indoor area collects too much moisture, mold and mildew can grow from the spores. Almost all homes, apartments, and commercial
buildings will experience leaks, flooding, or other forms of excessive indoor dampness at some point, causing mold to grow. Most mold colonies go inactive when they become too dry and will produce millions of spores. Without proper sanitation, the
mold will grow back if these spores become wet again .
Mold is not the only problem caused by too much moisture indoors. Damp indoor environments invite house dust mites and microbial growth such as bacteria, yeast, and other fungi. Building materials and furnishings can emit chemicals when damp, and standing
water present indoors can lead to cockroach and rodent infestations .
Mold and Health
Mold can often produce bacteria, some of which can directly impact humans. They also produce allergens and irritants.
Typical symptoms of mold exposure include: allergic responses; asthma attacks; and irritated eyes, skin, nose, throat, and lungs of both mold-allergic and non-allergic people. Allergies are the type of diseases most often associated with molds.
The "toxic" black mold is Stachybotrys chartarum. Not all black molds are Stachybotrys chartarum. While it is less common than other mold species, it is not rare .
This toxic black mold is not deadly unless it is eaten. However, it is one of the causes of "sick building syndrome." Direct contact with this black mold can create common symptoms such as a rash (especially in areas that are normally sweaty), itchy
dry skin, pain and inflammation of the mouth and throat, conjunctivitis (pink eye), burning in the eyes and nose, tightness of the chest, cough, nosebleeds, fever, headache, and fatigue .
Generally it is not necessary to identify the species of mold growing in a residence, and the Centers for Disease Control and Prevention (CDC) does not recommend routine sampling for molds. Because each person reacts differently to mold (because of the
person's susceptibility or because of the type and amount of mold present), sampling and culturing are not reliable in determining personal health risk. If you are susceptible to mold and mold is seen or smelled, there is a potential health risk;
therefore, no matter what type of mold is present, it should be removed .
Step 1: Fix the Water Problem
Mold and other biologic growth is caused by condensation and is commonly found along the baseboards and windowsills in older housing units, particularly along the north wall. Condensation forms along the baseboards of the interior surface of outside walls
during colder weather, particularly behind furniture where forced air from the furnace cannot reach. Biologic growth from condensation can be caused by poor sanitation, elevated humidity levels caused by poor air circulation in the home, and/or poor
construction of exterior walls and windows.
Short-term solutions for condensation in the home include:
- Reducing the humidity level in the house to 30% and 50%
- Using an air conditioner or a dehumidifier during humid months
- Not placing any furniture against the north exterior walls during cold weather. This allows heated air and radiant heat to warm the walls.
Intermediate and long-term solutions include:
- Making sure the home has enough ventilation, including exhaust fans
- Cleaning the affected walls and repainting them with paint that has added mold inhibitors. This is recommended for all bathrooms.
- Not carpeting bathrooms and other areas affected by condensation
- Redirecting forced heat vents so that they are along the outer walls, particularly below windows. This is expensive and may not be necessary.
- Insulating or increasing the insulation value of the exterior walls of the home
Step 2: Remove Moldy Furniture & Upholstery
You must remove or replace previously soaked (wet for more than 24-48 hours) porous materials (e.g., carpets, carpet pads, and upholstery) with visible mold. Clothing and similar items (e.g., blankets, pillowcases, curtains), however, can be machine washed.
Step 3: Clean Hard Surfaces
You can clean up the mold on hard surfaces using a cleaning solution. Remember to ALWAYS follow the manufacturer's instructions when using bleach or any other cleaning product.
Mold can be removed by cleaning hard surfaces with:
- a household disinfectant labeled effective against mold,
- a vinegar or baking soda solution (Many resources for homemeade solutions are available online, such as at WikiHow.)
- a detergent solution, then sanitizing with a bleach solution (1/4 cup of bleach in 1 gallon of water), or
- a bleach solution of no more than 1 cup of bleach in 1 gallon of water
If you choose to use a bleach solution:
- Never mix bleach with ammonia or other household cleaners. Mixing bleach with ammonia or other cleaning products will produce dangerous, toxic fumes.
- Open windows and doors to provide fresh air
- Wear non-porous gloves and protective eye wear
- If the area to be cleaned is more than 10 square feet, consult the Mold Remediation in Schools and Commercial Buildings Guide by
the U.S. Environmental Protection Agency (EPA). Although focused on schools and commercial buildings, this document also applies to other building types.
If you notice any dry wood joists and studs that are structurally sound but show evidence of biologic growth (darkened or black), you may encapsulate them with a mold sealant after cleaning.
- Centers for Disease Control and Prevention, Mold – Basic Facts
- Damp Indoor Spaces and Health ISBN: 0-309-09193-4, 380 pages, 6 x 9, hardback (2004)
- Centers for Disease Control and Prevention, Facts about Stachybotrys chartarum
- American Phytopathological Society, Stachybotrys chartarum: The toxic Indoor Mold
Related Links: CDC: Mold, EPA: Mold, EPA: Mold and Asthma, OSHA: Workplace Mold