Article from IEQ Review

The most ubiquitous contaminants of inside air quality are microbiologic agents. They are also the most frequently overlooked sources of reduced quality when evaluating inside air. Concerned providers such as building owners, property managers and consultants of quality air have taken a new and more critical approach to determining microbial source, quantity and identification.

It was at one time sufficient to state, "There must be a mold present, you can smell it." Today, it is known that the quantity, site and identification of microbes are required to properly complete an evaluation. Many microbial problems are dose-related; for example, a small amount may not cause a problem, whereas, a larger amount may cause significant deterioration of air quality. Thus, "acceptable levels" for microbes comparable to those for toxic chemicals must be established. Such standards would provide baseline data for any building, or location, to determine its current condition and, where appropriate, treatment success. Eventual databases will permit air quality specialists to rapidly and inexpensively differentiate between transient and colonized growth within air supply systems.
Bacteria, fungi, protozoa, viruses, mites and other microbes affect indoor environments in various ways. They also affect persons differently. Though generalized indicators of distress are recognized, the degree of distress differs with each affected person. This could easily be termed a tolerance level, but more correctly it reflects the diversities in immunologic capacities each of us has.

Disease: Many of the microbial airborne contaminants are pathogenic. They have the ability to cause disease directly. Headlines have made many of the relatively obscure diseases familiar to even the youngest readers; legionnaire's disease and tuberculosis are good examples. Interestingly though, measles, influenza, chicken pox and rubella are diseases known to be transmitted by inside air, thus indicating poor air quality.

Allergic Responses: Watery eyes, runny noses and respiratory distress (asthma) are common allergic responses. Microbiologic products may alter inside air and cause allergic distress.

Toxins: Toxic compounds, are called mycotoxins and are produced by many fungi, which have been associated with "sick building syndrome." Some of the mycotoxins are potent enough to have been considered for agents in germ warfare. Their presence suggests a dangerous environment and may lead to building closure, at this time, little is known of the toxic affects from bacterial toxins distributed by air.

In future columns, I will discuss specific organisms and their contributions to the problems of indoor air pollution. There are a multitude of microbiologic agents, quantitative analysis of their presence and documentation of their influence is only the beginning of eradicating the problem.

For more information contact:
Dr. Rajiv R. Sahay
(800) 422-7873 ext. 204
laboratory@pureaircontrols.com