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Flooded buildings may harbor mold
MISSISSIPPI STATE -- Thousands of buildings across the Gulf Coast may have survived the winds of Katrina only to fall victim to health-threatening mold spores.
"Mold and mildew are always challenges in Mississippi because they thrive in warm, humid, and damp or water-damaged conditions," said Herb Willcutt, safety specialist with the Mississippi State University Extension Service. "The storm surge and heavy rains brought in by Katrina are likely to contribute to an explosion of mold spores in these areas."
Molds and mildews are forms of fungi found year-round both indoors and outdoors. Unsightly molds have odors, can cause health problems and can damage structures. Fungi, including molds, spread through the air by producing microscopic spores. These spores establish new colonies wherever they encounter favorable conditions for their growth.
"Residents with flooded or water-damaged homes need to remove wet materials as soon as possible. This may include sheet rock, paneling and insulation if water stood in the damaged rooms long enough to wet the insulation. The sooner the drying process begins, the better," Willcutt said. "Wear gloves and a mask whenever handling moldy materials."
Clean and disinfect hard plastic, glass and metals by applying a solution of 1 cup of chlorine bleach per 1 gallon of water or follow manufacturer's recommendations. Thoroughly wet the surface with the solution for 10 to 15 minutes to kill the mold. Allow the solution to dry naturally in six to eight hours.
Throw out or completely decontaminate moldy porous materials. Use non-ammonia soaps or detergents to remove mold, but never mix bleach and ammonia.
With buildings on conventional foundations, make sure there is plenty of ventilation in the crawl space. Keep indoor humidity low by using fans, air conditioners or dehumidifiers if electricity is available. If not, open windows to increase air circulation as much as possible.
Willcutt warned that it is a mistake to rebuild or repair before wood is sufficiently dry.
"Wood should have a moisture content of less than 15 percent before drywall, paneling or other coverings are placed on the wood. Do not seal up walls until the wood moisture content is at least down to 15 percent. This can be determined with a moisture meter," Willcutt said. "These meters can reveal if there is excess moisture in the crawl space, attic or framing wall."
Beverly Howell, state program leader for Extension family and consumer sciences, said moisture meters are on their way to county Extension offices in the hurricane-damaged counties in Mississippi.
"Our goal is to have them ready when Mississippians are ready to repair and rebuild homes that were flooded by Hurricane Katrina," Howell said. "We know everyone is eager to repair damage, but rebuilding too quickly after a flood can result in more problems down the road. Accurate use of these meters is the best way to avoid mold growth, insect infestations, and deterioration of the wood and wall coverings."
Jane Clary, Extension health specialist, said some molds produce toxic substances called mycotoxins, which can cause problems when inhaled.
"Most people have no reaction to molds, but some experience irritations and allergic reactions similar to that caused by pollen or animals," Clary said. "Molds can aggravate asthma, and in rare cases, cause more serious health problems."
Among those more susceptible to mold problems are the elderly, infants and children, pregnant women, and those with respiratory conditions or weakened immune systems.
Be cautious when using bleach indoors. Read the label and provide adequate ventilation.