Mold Coloration and Toxicity: What do you need to know?

Mold has become an issue of increasing concern to the general population as lawsuits, media attention and misinformation fuel fires of hysteria.  To further complicate matters, a lack of education and scientific knowledge leads the layperson to correlate the presence of “black mold” with various ailments attributed to “toxic molds”.  In order to dispel mold myths and provide professional assistance to the average person concerned about mold contamination, it is critical to understand the complex nature of mold.

Mold Defined:

Scientifically, mold is visual growth produced on substratum and/or on host by a group of filamentous fungi (fungi with true mycelium). Taxonomically, fungi are a group of Eukaryotic organisms placed under the lower group of the plant kingdom. These organisms are devoid of chlorophyll and their cell wall is made up of chitin and glucans. They are heterotropts. It may be saprophytic, parasitic or both or may be living symbiotically with other living organisms. Their role in the ecological system is very vital and important as decomposers.

Mold Coloration:

Coloration and toxicity are two separate trends in mold. The coloration of mold is governed by pigmentation, physiological activity and genetics of the organism. The production of toxins is highly influenced by the nature of metabolites produced by the mold and others factors including environmental conditions. Hence, the toxicity of the mold should not compare directly with the color of the microorganism.

Mold Toxicity:

Naturally occurring molds may also be toxic in nature. Toxic molds are capable to secrete a number of toxic chemicals that are harmful to living entities.  Mycotoxins, glucans and microbiological volatile organic compounds (MVOC) are amongst the most prominent toxic substances produced by mold and other fungi. The strength of these toxins, however, is greatly varies depending upon the species/strain of microorganisms.  There is no proven or documented record that the toxicity of these chemical compounds is related to the color of the organism. In general, “black mold” refers to all molds that are black in color, but not all the black molds are toxic.  Nigrospora, for example, is a black mold but there is no sufficient evidence that it is toxic to humans or other living organisms.

It is also important to note that a number of molds not black in color are capable of releasing mycotoxins that initiating diseases or allergenic responses in susceptible individuals. Blastomyces, Candida, Emmonsia, Ganoderma, Microsporum, Mucor, Rhizopous and Trichophyton etc. are some common molds that cause a number of health and hygiene problems but are not black in color.  The entire Penicillium group is associated with a number of indoor air problems but not black in color. Aspergillus is a major group of toxic molds but many species of Aspergillus are not black (i.e. A. candidus) however, some species of Aspergillus is black in appearance morphologically (example: Aspergillus niger).

Conclusion:

It is not appropriate to refer to all “black mold” as a “toxic mold”.  As we have discussed, not all black molds are neither all-toxic molds are black in color.  Misinformation on toxic mold is rampant.  It is impossible to grossly observe a mold and determine its toxicity by its pigmentation.  The best way to identify the type of mold present in an environment is to take a direct surface or air sample and send it to a qualified laboratory for further analysis and evaluation. The laboratory report helps in the determination of presence of mold and its toxic nature.

 
The Environmental Diagnostics Laboratory (EDLab) at Pure Air Control Services performs a wide array of mold assays (fungal identification).  EDLab can identify molds by using various techniques.  Some common analysis performed by EDLab to identify fungi and mold associated test includes, but not limited to, the Bio-Scan and Spore Trap Analysis beside mycological culturable analysis of air/bulk/surface/swab/liquid environmental samples. The type of sampling and analysis performed is determined by project specifications project requirements or individual needs.

For additional information you can contact Dr. Rajiv Sahay, Director, EDLab, Pure Air Control Services, www.pureaircontrols.com 1-800-422-7873 ext 303.

About Pure Air Control Services, Inc.

Alan Wozniak founded Pure Air Control Services, Inc. in 1984 as a small mechanical contracting firm. Today, the firm sets the industry standard for indoor environmental quality diagnosis and remediation.

Pure Air’s nationally performed services include: Building Sciences Evaluation; Building Health Check; an AIHA accredited Environmental Microbiology Laboratory; Environmental Project Management; and Mold Remediation Services, among other indoor environmental services.

The company’s expanding client roster includes the FAA, Walt Disney World, General Services Administration (GSA); Allstate Insurance; CBRE, Carrier Air Conditioning; NAVFAC, DOT, USACE, US Army, and many other Fortune 500 companies, school boards, and city, state, and county governments, making Pure Air Control Services the reliable industry leader.

For more information on Pure Air Control Services, Inc. please contact Alan Wozniak or Cy Garner at (800) 422-7873 ext 802 or 804 respectively, or visit www.pureaircontrols.com.