Here is an interesting read from the
Tech Environmental e-Newsletter - September 2004
DISTINGUISHING BETWEEN "TOXIC MOLD" AND MOLD HYSTERIA
We have all heard the sound bites: "COUPLE BURNS DOWN HOUSE TO RID THEMSELVES OF TOXIC MOLD"; "TOXIC INTRUDER: BLACK MOLD PANIC HAS FAMILIES FLEEING THEIR HOMES", and "MOTHER WORRIES ABOUT TOXIC MOLD IN SCHOOL". But the question remains: Is mold really a problem? Separating the media hype from reality is often difficult.
It seems like everywhere you turn lately there is a story about "toxic mold" shutting down a city school or town hall. The news of building closings and stories about private homes being abandoned due to mold are on TV, in the newspapers, and in magazines. Individuals in biohazard suits and masks who you would expect to see at a hazardous waste site usually accompany these stories, making it difficult for the public to separate mold fact from fiction, and to determine if mold is really a "growing" concern.
IS MOLD A NEW PHENOMENON?
No. Basically, mold is present everywhere, both indoors and outdoors. Given the right conditions (excess moisture), mold can grow on almost anything. Cellulose materials such as paper and paper products, cardboard, ceiling tiles, wood, and wood products are particularly conducive for the growth of some molds. Mold always has been and always will be present in housing and public buildings.
WHY DOES MOLD SEEM MORE OF A CONCERN TODAY?
In addition to heightened awareness, mold and other indoor air quality (IAQ) issues have been increasing because of tighter building construction practices to save energy. These "green building" practices reduce ventilation rates and do not allow air to escape. Less infiltration means fewer air exchanges, which can lead to moist conditions where mold can grow.
IS MOLD TOXIC?
The Centers for Disease Control has noted that the term "toxic mold" is not accurate. Mold spores are typically not toxic, although certain molds are toxigenic, or toxin producing. There are actually very few reports of health concerns from toxigenic molds found inside homes and offices, and a causal link between the presence of the toxigenic mold and health conditions has not been proven.
IS MOLD HARMFUL?
Mold spores can be irritants to humans and can cause asthma or allergic reactions based on the concentrations present and a person�s individual tolerance level. In individual homes, irritant reactions are usually caused by large mold concentrations. For schools and other public buildings, where there are significantly more people exposed and therefore more chance of having a sensitive individual(s), the concern is possible at lower concentrations. People with compromised immune systems or lung disease are more susceptible to fungal infections.
WHAT IS THE VALUE OF MOLD SAMPLING?
As environmental professionals, we all know that exposure concerns and interpretation of sampling results are never as "black and white" as the simple comparison to a standard. Sampling and comparison to standards or guidelines are only one benefit of test data collection and analysis. Most indoor air quality experts agree that there should be mold exposure standards, and that there will be standards in the future. In the meantime there are many advantages to qualifying and quantifying mold prior to and after clean up.
Indoor mold sampling results compared to ambient conditions can identify mold spores and determine which molds are growing indoors. Swab or mold spore counts can determine growth rates and dominate species of concern, respectively. These data can help explain allergic or irritant reactions. In cases of toxigenic gas concerns, sampling of what the molds "exhale" or off-gas can determine exposure concerns and help assess insurance claims.
Given the media hype and fear about "toxic mold", there is a public backlash with people demanding complete and thorough mold remediation. Because of this, many projects are being performed with excessive remediation to ensure their ultimate success. The expense of full scale, dispose-of-everything, remediation is often unwarranted. Mold sampling can be used to determine the level of remediation that is necessary and to confirm that the level of remediation recommended and performed has been effective.
If you would like to discuss this article or if you have any questions about mold sampling, please contact us.
Dana C. Buske, PhD
Environmental Scientist
DBuske@TechEnv.comExtension 109
Robert J. Rossi, PhD, CCM, QEP
Senior Atmospheric Scientist
RRossi@TechEnv.comExtension 111