Special Section Archives — The Altamont Enterprise, September 22, 2011
Research from the Centers for disease control offers help for combating mold after a flood
After hurricanes Katrina and Rita struck in 2005, causing extensive flooding and mold in over 100,000 homes, an estimated 46 percent, the Centers for Disease Control commissioned a report on mold to serve as a guide for health officials and the general public. That 43-page report, Mold Prevention Strategies and Possible Health Effects in the Aftermath of Hurricanes and Major Floods, explains that molds, mushrooms, mildews, and yeasts are all fungi, a kingdom of organisms distinct from plants and animals.
Unlike animals, fungi have cell walls, but, unlike plants, fungal cell walls are made mostly of chitin and glucan; fungi can’t produce their own nutrients the way plants do through photosynthesis. Rather, fungi secrete enzymes that digest the materials in which they live and absorb the released nutrients.
Molds are everywhere, indoors and out, and spread and reproduce by making spores, which are small and lightweight, and able to travel through air and survive a long time. Some molds produce toxins.
All molds need moisture and nutrients to grow; wood, wallboard, wallpaper, upholstery, and dust can all be nutrient sources. “Flooding, particularly when floodwaters remain for days or weeks, provides an almost optimal opportunity for mold growth,” says the report.
Mold exposure, it says, can produce disease in several ways — through inhalation, skin contact, or ingestion. People with immune suppression — for example, from cancer therapy, from an HIV infection, or from having received an organ transplant — are at increased risk for infection from mold. People who have allergies or asthma are particularly susceptible to respiratory problems caused by mold.
Allergic responses can come from exposure to dead, as well as to living mold spores so killing mold with bleach may not prevent allergic responses. The Centers for Disease Control recommends that everyone avoid unnecessary exposure to mold, especially anyone at a high risk for infection. Infants, children, pregnant women, people with respiratory conditions, and the elderly are at a higher risk for adverse health effects from mold. Typical symptoms from mold exposure may include respiratory problems, sinus congestion, or a dry, hacking cough, eye irritation, nose, throat, and skin irritations, or headaches and other pain, according to the CDC.
“Any structure flooded after hurricanes or major floods should be presumed to contain materials contaminated with mold if those materials were not thoroughly dried within 48 hours,” says the report, Mold Prevention Strategies. It recommends a visual inspection of ceiling tiles, wallboard, and ventilation systems, while noting contamination of interior wall cavities is common.
The CDC says mold can be recognized by sight, if walls or ceilings are discolored, or by smell, if there’s a musty, earthy odor or a bad stench. In its guidelines for re-entering a flooded home, the CDC urges drying out the building within 24 to 48 hours, using fans, and urges, “When in doubt, take it out.”
The guidelines instruct, “Remove all porous items that have been wet for more than 48 hours and that cannot be thoroughly cleaned and dried. These items can remain a source of mold growth and should be removed from the home. Porous, non-cleanable items include carpeting and carpet padding, upholstery, wallpaper, drywall, floor and ceiling tiles, insulation material, some clothing, leather, paper, wood, and food.”
In a similar manner, the report, Mold Prevention Strategies, states, “The most effective way to eliminate mold growth is to remove it from materials that can be cleaned, and to discard materials that cannot be cleaned or are physically damaged beyond use. Persons with respiratory conditions, allergies, asthma, or weakened immune systems should avoid mold cleanup if possible or seek the advice of their doctor and determine what type of personal protective equipment is appropriate.”
The PPE, as the gear is called, should include a tight-fitting respirator, rubber gloves, and goggles.
For cleaning mold areas less than 10 square feet, the report recommends using a solution of one cup chlorine bleach for each gallon of water, and stresses that bleach should never be mixed with ammonia. Once the area is scrubbed, it should be rinsed with clean water and dried. For mold growth covering more than 10 square feet, it refers to the Environmental Protection Agency’s guide, Mold Remediation in Schools and Commercial Buildings.
Two trade groups that may help locate professionals for cleanup are the Association of Specialists in Cleaning and Restoration (http://www.ascr.org) and the Institute of Inspection, Cleaning, and Restoration Certification (http//www.iicre.org). Homeowners are urged to check references and ask the contractor to follow the guidelines of the American Conference of Governmental Industrial Hygienists.
To clean clothes and salvage household items, the report stresses to use only water that is safe, and to use hot water and a disinfectant or sanitizer. “Do not burn or bury textiles that cannot be cleaned,” it says. “Put them into properly sealed plastic bags and dispose of them as you would normal household garbage in your area.” Similarly, the personal protective equipment worn while cleaning up should be discarded in impermeable bags after use.
“All buildings with extensive mold contamination require remediation before rehabilitation,” says the report. Remediation includes making structural repairs to prevent further water intrusion, removing mold-contaminated materials that can’t be cleaned and decontaminated, and cleaning and decontaminating materials that can stand such treatment.