Aging effects continued correspondence

II. Toxic dose. Because mycotoxins are not volatile, exposure would require inhalation of aerosolized spores, mycelial fragments, or contaminated substrates. The toxic inhaled dose of mycotoxin for humans is not known. Based on experimental data from single-dose in vivo studies, Stachybotrys chartarum spores (in-tranasally in mice or intratracheally in rats) high doses (more than 30 million spores/kg) can produce pulmonary inflammation and hemorrhage. The no-effect dose in rats (3 million ores/kg) corresponds to a continuous 24-hour exposure to 2.1 million spores/m for infants, 6.6 million spores/m for a school-age child, or 15.3 million spores/m for an adult. These spore concentrations are much higher than those measured in building surveys. 

Figure 6. Example of the self-healing effect. The load-deflection diagrams are from specimen SHT21 (RefC). The specimen was first loaded beyond ultimate at 123 days (dashed line at the left). It was reloaded at an age of about 400 days after storage in the fog room (continuous line at the right). The dotted line corresponds to the predicted behaviour of the specimen at 123 days, should the test not have been prematurely terminated.

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