Airborne Microbiota and their Disease, Ecological and Social Implications for 31 Major Chinese Mainland Cities

LU ZHANG, Maosheng Yao, Peking University

     Abstract Number: 355
     Working Group: Bioaerosols

Abstract
Microbial aerosol exposure represents a major health threat toward humans. Here, particulate matter (PM) samples from a total of 465 automobile air conditioning (AC) filters were collected from 31 major Chinese mainland cities to analyze the airborne distribution of bacterial, fungal and RNA viral communities. Our results showed that airborne microbiota including pathogenic microorganisms containing genera varied greatly among 31 major cities, thus representing different health risks. The relative abundances of some bacterial genera such as Brevibacterium were extremely high in PM from some cities such as Changsha. Significant north-south differences in fungi community structures were observed with higher abundances of Trichoderma and Phoma in northern China and higher abundance of Cladosporium in the south. Varying RNA virus structures were detected in 16 cities’ samples with family Virgaviridae abundant from over half of the 31 cities. Using redundancy (RDA), variance partition (VPA) and aggregated Boosted tree (ABT) analysis, environmental factors, especially relative humidity, were found to have played a leading role, followed by air pollutants and social factors. However, as for bacteria, social factors, especially the secondary industry, had the greatest impact on the bacteria community structures, followed by environmental factors and air pollutants. In contrast, only temperature was shown fitting with the relative abundance profile of top 20 bacteria and fungi genera based on random forest regression (R2= 0.774). Environmental, social-economic and ecological factors were found to form a unique microbiota fingerprint for a particular city. The structure was shown to be further influenced by interactions among the microbial agents as implied by their positive or negative associations across species. Information developed here is of great importance to develop geophysical microbial aerosol fingerprints, while providing national database for airborne microbes to guard human health.