The occurrence of aflatoxins, mutagenicity and cytotoxicity nature of dust samples from a converted library block into office space

Six week dust samples were collected from a newly renovated library block converted into office space, using two domestic vacuum cleaners; the results confirmed the presence of aflatoxins B₁, B₂, G ₁, and G₂ using HPLC. The amount of toxins recovered from both vacuum cleaners declined from 1967.3 ng/g (week1), to 19.1ng/g ng/g (week 6). Mutagens responsible for mutation from the dust samples were mainly direct-acting in the results of the Ames test using base shift mutation (TA98) and base repair mutation (TA100) Salmonella typhimurium strains with a mammalian metabolic activation (S9). The highest value was found in week 1 sample with TA100 of 100% response and 90% using TA98 strains. From the cytotoxicity result using both cells, the concentration of the extract, conforms to the positive response exhibited in the cell lines. Other toxigenic and non toxigenic moulds were also isolated.