The capability of fungi isolated from moldy dwellings to produce toxins

Abstract

Objectives: The main objective was analysis and assessment of toxinogenic capabilities of fungi isolated from moldy surfaces in residential rooms in an urban agglomeration situated far from flooded areas in moderate climate zone. Material and Methods: The assessment of environmental exposure to mycotoxins was carried out in samples collected from moldy surfaces in form of scrapings and airborne dust from 22 moldy dwellings in winter season. In each sample 2 mycotoxins were analyzed: sterigmatocystin and roquefortine C produced by Aspergillus versicolor and Penicillium chrysogenum, respectively. Mycotoxins were analyzed by high-performance liquid chromatography (HPLC) in: scrapings from moldy surfaces, mixture of all species of fungi cultured from scrapings on microbiological medium (malt extract agar), pure cultures of Aspergillus versicolor and Penicillium chrysogenum cultured from scrapings on microbiological medium; mycotoxins in the indoor air dust were also analyzed. Results: The production of sterigmatocystin by individual strains of Aspergillus versicolor cultured on medium was confirmed for 8 of 13 isolated strains ranging 2.1–235.9 μg/g and production of roquefortine C by Penicillium chrysogenum for 4 of 10 strains ranging 12.9–27.6 μg/g. In 11 of 13 samples of the mixture of fungi cultured from scrapings, in which Aspergillus versicolor was found, sterigmatocystin production was at the level of 3.1–1683.2 μg/g, whereas in 3 of 10 samples in which Penicillium chrysogenum occurred, the production of roquefortine C was 0.9–618.9 μg/g. The analysis did not show in any of the tested air dust and scrapings samples the presence of analyzed mycotoxins in the amount exceeding the determination limit. Conclusions: The capability of synthesis of sterigmatocystin by Aspergillus versicolor and roquefortine C by Penicillium chrysogenum growing in mixtures of fungi from scrapings and pure cultures in laboratory conditions was confirmed. The absence of mycotoxins in scrapings and air dust samples indicates an insignificant inhalatory exposure to mycotoxins among inhabitants in moldy flats of urban agglomeration situated far from flooded territories. Int J Occup Med Environ Health 2016;29(5):823–836

Keywords

• indoor air
• mycotoxins
• molds
• residential environment
• sterigmatocystin
• roquefortine C