Trichothecene mycotoxins respiratory exposure

Stachybotrys chartarum is one of the most commonly noted agents associated with so-called sick building or damp building-related syndrome and damp building-related illnesses (DBRI). While upper and some lower respiratory tract symptoms have been accepted as causally linked to human exposure to moldy damp indoor environments, other reported effects, including airflow obstruction, chronic obstructive pulmonary disease, pulmonary hemorrhage, neurologic effects and cancer, have not (Institute of Medicine, 2004). An excellent recent review of S. chartarum, associated trichothecene mycotoxins, and DBRI is available (Pestka et al, 2008). 

Trichothecene Mycotoxins. Only one class of easily produced, membrane-damaging toxins, the trichothecene mycotoxins, is dermally active. Therefore, they must be considered by standards different from those for all other toxins. Trichothecenes can cause skin lesions and systemic illness without being inhaled and absorbed through the respiratory system. Skin exposure and ingestion of contaminated food are the two likely routes of exposure of soldiers oral intoxication is unlikely in modern, well-trained armies. Nanogram quantities per square centimeter of skin cause irritation, and microgram quantities cause necrosis. If the eye is exposed, microgram doses can cause irreversible injury to the cornea. 

Later signs and symptoms (8-24 h) would probably be similar (except for the degree of skin rash and blisters) for both large-particle and deep-respiratory aerosol exposure to trichothecene mycotoxins. They could include continued nausea and vomiting, diarrhea, burning erythema, skin rash and blisters, confusion, ataxia, chills, fever, hypotension, and bleeding. 

No specific therapy for trichothecene mycotoxin poisoning is currently available. Skin decontamination with soap and water or the hypochlorite- (M258A1) or resin-based (M291) military decontamination kits can effectively remove toxin up to six hours after exposure, although none of them neutralize the toxin. Treatment of respiratory, dermal, and GI effects currently must be symptom based and supportive in nature. Superactive activated charcoal, for example, a common treatment for many orally taken poisons, has been shown to bind 0.48 mg T-2/gm charcoal in mice and improve survival rates significantly. 

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