COMPARISON OF CONCENTRATIONS AND SIZE DISTRIBUTIONS OF FUNGAL SPORES IN BUILDINGS WITH AND WITHOUT MOLD PROBLEMS

Concentrations and types of airborne fungal spores and their aerodynam ic sizes were studied in nine buildings with mould problems and in mat ched reference buildings in order to characterize the exposure in buil dings with mould problems. Samples were taken with Andersen six-stage impactors in the autumn and winter. In winter, total concentrations of fungal spores in buildings with mould problems were twice those in re ference buildings, even though all concentrations were quite small. In the autumn, the differences were less obvious due to the masking effe ct of outdoor air fungi. Also, the compositions of fungal genera diffe red in buildings with mould problems from that in reference buildings. The difference was most significant in the size range 2.1-4.7 mum. Th e size distribution of fungal spores in dwellings with mould problems skewed towards larger particles than in reference dwellings. The obser ved differences in size distribution indicate differences in airborne behaviour of fungal spores and, consequently, in respiratory exposure.