While many in America have nervously inspected their mail for the powdery white substance pointing to anthrax contamination, the U.S. Environmental Protection Agency (EPA) urges the public to remain on guard against another toxic substance: mold.
The EPA ranks indoor air pollution among the top four environmental risks facing Americans, a statistic compounded by the lack of regulations governing indoor air quality.
Able to grow on virtually any moist surface, mold is nearly impossible to completely eliminate. The best method of controlling mold is controlling moisture. If mold growth goes unchecked, it can cause illness. A particularly toxic form of mold, Stachybotrys, is contributing to mold-related illnesses and sick building syndrome.
Sick building syndrome may be diagnosed when occupants experience a wide range of symptoms including headache, congestion, dizziness, nausea, drowsiness and depression, with no one identifiable cause. When air-handling systems have become contaminated, re-circulating toxic air intensifies the spread of airborne mold spores.
Identifying Toxic Mold
Stachybotrys chartarum, also referred to as Stachybotrys atra, is a greenish-black mold that grows on materials with a high cellulose and low nitrogen content, such as paper, wood, insulation and gypsum fiberboard. Although not unusual, neither is it the most common form of household mold. Stachybotrys is, however, establishing a reputation for dangerous toxicity. Both “48 Hours” and the “Today Show” have investigated claims of severe physical and mental illness resulting from mold infestations. Lawsuits in Texas and California contend that mold exposure has led to serious illness and death.
Despite the failure of science to definitively demonstrate a causal connection between mold exposure and severe illness, litigants blame conditions such as congestion, fatigue, bloody cough, neurological difficulties and learning disabilities on the spore producer.
Other symptoms commonly associated with airborne mold include breathing difficulty, nasal and sinus congestion, eye and throat irritation, cough and skin rashes. People with allergies, immune deficiencies, asthma or other sensitivities may experience more severe reactions.
California mold lawsuits include construction defect and personal injury claims, according to The Legal Intelligencer.
Although some plaintiffs can prove a correlation between their physical illness and mold, most cases settle out of court.
The majority of Texas cases have concentrated on insurance coverage issues. Mold damage is covered under Texas homeowner policies when it’s caused by an accidental event, such as a burst pipe or flood. Last June, a Texas jury awarded one woman $32 million for damage to her 22-room home when her insurer, Fireman’s Insurance Exchange, had been warned of mold growth but had refused to completely address the water damage to her home. The house became infected with Stachybotrys and the family began experiencing health problems.
While much of the mold-related litigation has occurred in Texas and California, no one theory entirely explains is proliferation in those regions. Climate does not appear to be a factor. The prevalence of less durable building materials in mild climates may have an impact, but the influence of successful lawsuits could also be a contributing factor to the number of claims filed in those states.
In October Chicago’s St. Charles East High School closed for mold cleanup after students and staff complained of headaches, fatigue and respiratory problems. One student filed suit, blaming her chronic sinus infections and headaches on the presence of Stachybotrys mold, after a battery of environmental tests revealed the fungus in drywall, ceiling tiles, cabinets and under sinks.
School district spokesman Tom Hernandez said the district will pay Clean World Engineering $1.27 million to eradicate the mold over a five-month period, and to conduct 18 months of follow-up tests.
Ohio is the site of another severe reaction to Stachybotrys. In the final months of 1994, the Centers for Disease Control and Prevention led a case-control investigation on 10 of the 45 reported cases of pulmonary hemorrhage reported in young infants in the Cleveland area. Most of the cases occurred within contiguous zip codes on the city’s east side, and all of them in flood-damaged homes. Sixteen of the infants died. The study found an epidemiological connection between pulmonary hemorrhage in the infants and water-damaged homes containing the toxic fungi. Stachybotrys atra was found in high quantity.
However, the connection is not conclusive, and the CDC warns that other factors — such as tobacco smoke — can act as crucial triggers precipitating overt pulmonary hemorrhage.
Nevertheless, the CDC remains convinced a link exists.
In the Air
During its growth phase, Stachybotrys is covered by a wet slime layer, but as it dries, it releases spores into the air as it reproduces. The EPA reports that Stachybotrys atra produces small molecular toxins (mycotoxins) that present a potential hazard when inhaled.
Since 1991, using the Dynamic Microbial Test Chamber, the EPA has conducted research into the environmental conditions that permit building material colonization by fungi, and the subsequent development of contamination sources.
There is still little information on the dynamics of fungal spore release from contaminated surfaces. Although it is widely agreed that high humidity must be present, it remains unclear how factors such as activity and airflow enable or promote emission.
According to the CDC, Stachybotrys grows on cellulose products that have been wet for at least a few days. Flood-damaged buildings are prime targets. It does not grow on plastic, vinyl, concrete or ceramic products.
The mold is black and slimy when wet. Once it dries out, it ceases growing, but the black dust it creates can be sucked up by the furnace or air conditioner blower, and spread throughout the building. Older furnaces that pull air from the basement may be dredging up spores.
The best way to identify a potential mold problem is to use your eyes and nose. Obvious signs include visible mold, an earthy or musty smell, and signs of excess moisture or water damage — watermarks, discoloration, leaks, standing water.
Two types of tests are available to identify the presence of mold: surface sampling and air sampling. Surface sampling involves collecting samples from various places within a building. Air sampling tests determine the quantity and type of mold spores in the air at a given point in time.
Neither test can identify whether mycotoxins (the disease-causing agents) are airborne.
In fact, the Minnesota Department of Health does not recommend testing for mold. It suggests assuming a mold problem exists if there is even cause to suspect it. The California Department of Health Services warns that no known medical tests can establish exposure to Stachybotrys; therefore, the best measure is prevention.
The Best Cure
Because indoor air quality, and specifically mold, continue to be significant liability concerns for developers, contractors, building owners and business tenants, many are looking at simple, cost-effective ways of taking proactive measures to prevent problems.
Clean, dry buildings will diminish the potential health hazard of indoor air pollution, from dust mites to Stachybotrys and other molds. These biological pollutants may cause health problems as mild as allergic reactions, but also can trigger more serious conditions, induce asthma attacks, spread disease, and in severe cases, cause death.
The Minnesota Department of Health advises that the most important step in solving a mold problem is to identify and correct the moisture sources that allowed the growth in the first place. Common indoor moisture sources include: flooding, condensation caused by high indoor humidity, roof and plumbing leaks, humidifier use, basement seepage, improper venting of combustion appliances and dryers, firewood stored indoors, line-drying clothes indoors, and houseplants.
The EPA recommends maintaining a building’s humidity between 20 to 40 percent in the winter and 60 percent the rest of the year. Adequate ventilation and air circulation are crucial in minimizing moisture and condensation. Basements and crawl spaces also should be properly ventilated to prevent moisture buildup. Exhaust fans in bathrooms and kitchens reduce levels of moisture and organic pollutants that vaporize from hot water.
Appliances that come in contact with water, such as humidifiers and refrigerators, should be kept clean, and their drip pans emptied. Major appliances including furnaces, heat pumps and air conditioners should be professionally inspected and cleaned annually. Drains should be disinfected regularly.
The American Red Cross/FEMA booklet “Repairing Your Flooded Home” says to be patient in thoroughly drying flood-damaged homes, but that items that have absorbed excessive moisture and have become moldy should be removed, bagged and discarded.
In general, any material that cannot be completely cleaned and dried should be discarded; this can include building materials, such as wallboard, fiberglass insulation, plaster and carpeting. Porous materials that have contacted sewage should be thrown away. CEG