Characteristics of airborne microbial pollution in indoor environments in Beijing
北京市居家空气微生物污染特征

The characteristics of airborne microbial pollution indoor were investigated. Indoor air samples were collected with imitated six-stage Andersen samplers in 31 family homes with children in Beijing. Results showed that the total microbial concentration, bacterial concentration and fungal concentration ranged from 269 CFU·m-3 to 13066 CFU·m-3, 47 CFU·m-3 to 12341 CFU·m-3, and 62 CFU·m-3 to 3498 CFU·m-3, respectively, and the mean concentration was 2658 CFU·m-3, 1821 CFU·m-3, and 837 CFU·m-3, respectively. The concentration percentage of bacteria and fungi was 61.0% and 39.0%, and the bacterial concentration was significantly higher than that of airborne fungi. Amongst all the airborne bacteria, Micrococcus was the most dominant bacterial genus, followed by Bacillus, Staphylococcus and Kocuria. These four bacteria genera in total accounted for about 63.1% to 70.9% of total airborne bacteria. The predominant fungal genera were Penicillium (36.0%), Cladosporium (17.8%), Aspergillus (9.3%), Alternaria (5.3%), and Phoma (3.6%). Finally, the control strategies of airborne microbial pollution from pet raising, air conditioner cleaning, indoor and outdoor environment preservation, refuse disposal, and indoor flower planting were provided based on the pollution characteristics of airborne microbes in family homes in Beijing.