Microbial activity levels in atmospheric bioaerosols in Qingdao

Abstract

Bioaerosols are an important subgroup of atmospheric aerosols, and microorganisms are a major component of bioaerosols. Microbial activity can affect climate change, human health and environmental processes. We developed a diacetate (FDA) hydrolysis method to measure microbial activity in bioaerosols. A large number of preliminary experiments were used to optimise the experimental conditions and guarantee the applicability of this assay to environmental bioaerosol samples. The level of microbial activity in the atmosphere in the Qingdao coastal region was measured using the FDA method in May and from September to December 2012. The microbial activity in bioaerosols varied from 10.7 to 85.8 ng/m3 sodium fluorescein, with an average of 30.2 ng/m3. The microbial activity in bioaerosols displayed monthly variations, with the highest value in May. However, the activity showed no significant correlation with temperature, relative humidity and wind speed. Thus, further study is needed to elucidate the major factors and mechanisms that affect microbial activity in the atmosphere.