Characteristics of airborne microfungi in subtropical homes

Because of high relative humidity (60-90%) and mild temperature (15-37 degrees C) all year round, fungi grow more quickly and easily in Taiwan, a subtropical country. Field evaluations of airborne fungi indoors and outdoors in two major types of cities (Taipei and Tai-Chi) in Taiwan were conducted during the fungus concentration peak season. Two-stage Andersen culture plate impactors were used to determine the number concentrations, genus and respirable fraction of indoor and outdoor fungi. The geometric mean concentrations of indoor and outdoor fungi in these two areas were found to be > 1000 colony forming units (CFU) m-3. In addition, Aspergillus, Penicillium, Cladosporium and yeast were observed to be dominant and their number concentrations in some homes exceeded 1000 CFU m-3. Moreover, the indoor and outdoor concentrations of the abundant fungi were found to be moderately correlated.