In an area representative of a moderate climate zone (Lubuskie Province in Poland), mycological tests in over 270 flats demonstrated the occurrence of 82 species of moulds. Aspergillus versicolor Tiraboschi was often encountered on building partitions (frequency 4: frequently). The ability to synthesize the carcinogenic sterigmatocystin (ST) means that it poses a risk to humans and animals. Biotoxicological tests of biomasses of A. versicolor were conducted in the Microbiological and Toxicological Laboratory, using the planarians Dugesia tigrina (Girard). The obtained results of the tests covered a broad range of toxicity levels of isolated strains: from weakly toxic (100-1000 mg·L(-3)) to potently toxic (1-10 mg·L(-3)). The high-performance liquid chromatography (HPLC) physicochemical method confirmed the ability of A. versicolor strains to synthesize sterigmatocystin. All of the samples of the air-dry biomasses of the fungi contained ST in the range between 0.03 and 534.38 mg·kg(-1). In the bio-safety level (BSL) classification A. versicolor belongs to category 1. Additionally, A. versicolor is an allergenic mould.
Keywords: Aspergillus versicolor; biotests; moulds; residential buildings; sterigmatocystin (ST).