POTENTIAL TOXIN PRODUCERS IN MATERIAL, AIR AND SURFACE SAMPLES

摘要

In water-damaged buildings, material samples (n=1084) contained high concentrations of microbes and potential toxin producers, most of which were most prevalent in sand bed under the buildings. In air samples (n=151) taken from inner space of construction the average concentration of fungal spores was 105 cfu/m3 and that of Streptomyces-bacteria 104 cfu/m3, although microbial concentrations were lower than the detection limit in 74 % of the samples. Aspergillus versicolor was the most common potential toxin producer, its prevalence being 23 % in material samples, 7 % in air samples from constructions and 10 % in surface samples. The concentrations of viable microbes and the prevalence of toxin producers on the surfaces (n=275) varied according to the material. Toxic fungi were most characteristic of gypsum board. Potential toxin producers seem to be quite common in water-damaged buildings, although several factors seem to affect their prevalence and concentrations.