Interview with Dr. Thrasher Part Two

This is a continuation of my discussion with toxicologist Dr. Jack Thrasher. The terminology is difficult but the point is clear. Mold is dangerous. In addition, the bacteria associated with indoor air contamination is dangerous. This is what sets Dr. Thrasher apart in my mind. The bacteria issue is rarely addressed when discussing mold.

3. Can you briefly describe what mold does to the human body?

This question refers to molds. You should also include the bacteria present in water damaged structures.

Molds can affect humans and animals in several ways. These include infection and/or colonization. The most classic being aspergillosis. These states can lead to mold-related nodules called mycetomas. Molds also produce toxins that affect animals and humans through their toxicological actions. These include inhibition of protein synthesis, mutation of DNA, cancers, severe activation of the immune system and increased production of various cytokines. Also, molds (Stachybotrys chartarum, 11 species of Aspergillus and species of Penicillium) produce hemolytic proteins that can cause bleeding of the lungs, nasal cavity and G.I. tract. Various species of molds can cause reactive airway disease, e.g. asthma and hypersensivity pneumonitis. The corticosteroids used to treat the inflammation associated with these two conditions are risk factors for developing aspergillosis.

Four species of Aspergillus (flavus, niger, fumigatus, and terreus) which can cause aspergillosis have been identified as causative organisms. These four species produce a highly toxic mycotoxin, Gliotoxin. Gliotoxin has been identified in the sera of patients with aspergillosis as well as in sera of animal models of this infectious process. Gliotoxin is a DNA mutagen, suppresses the immune system, causes cell death (apoptosis) and demyelination of the nervous system. Aspergillosis is on the increase worldwide in both immune competent and immune compromised humans. Do I need to say more on this subject?

Bacteria in the indoor environment can also be pathogenic. The bacteria of current concern include three genera of the actinobacteria: Streptomyces, Nocardia and Mycobacterium. Streptomyces and Nocardia produce toxins that cause cell damage and death. In addition. Streptomyces californicus and its toxins act synergistically with macrocyclic trichothecenes in mouse models. Also, various species of Streptomyces are the sources of chemotherapeutic agents and various antibiotic, e.g. Streptomycin. Very little information is available on the toxins produced by Nocardia. With respect to Mycobacterium there is a worldwide problem. Mycobacteria can cause two types of lung infections: tuberculosis and nontuberculous mycobacteria (NTM) lung disease. The American Thoracic Society states in 2007 that NTM (also called Mycobacterium avium complex or MAC) lung infection is on the increase worldwide in immune competent and immune compromised humans. My professional opinion is this has resulted from contaminated indoor air. Finally, the CDC recognizes that these organisms also cause hypersensitivity pneumonitis.. Streptomyces and Mycobacterium can cause nodules (tumors) known as eumycetomas.