Airborne bacterial communities of outdoor environments and their associated influencing factors

• Published in: Environment international Vol. 145; p. 106156
• Main Authors: Ruiz-Gil, Tay, Acuña, Jacquelinne J., Fujiyoshi, So, Tanaka, Daisuke, Noda, Jun, Maruyama, Fumito, Jorquera, Milko A.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.12.2020; Elsevier
• Subjects: Aerosols; Air Microbiology; Airborne bacteria; Atmosphere; Bacteria - genetics; Bacterial communities; Bioaerosols; Fungi; Microbiota; Outdoor environments; Airborne bacteria; Bacterial communities; Outdoor environments; Atmosphere; Bioaerosols
• ISSN: 0160-4120; 1873-6750
• DOI: 10.1016/j.envint.2020.106156

[Display omitted] •Studies have revealed a wide diversity of bacteria in the atmosphere.•Atmospheric factors regulating airborne bacterial communities need to be elucidated at local and global level.•Airborne bacteria are relevant to public health, agriculture, and also remediation and atmospheric processes.•Specific bacterial taxa may act as microbial indicators of specific bioaerosol sources and seasonality.•Airborne bacteria can be bioprospected for their potential in biotechnology. Microbial entities (such bacteria, fungi, archaea and viruses) within outdoor aerosols have been scarcely studied compared with indoor aerosols and nonbiological components, and only during the last few decades have their studies increased. Bacteria represent an important part of the microbial abundance and diversity in a wide variety of rural and urban outdoor bioaerosols. Currently, airborne bacterial communities are mainly sampled in two aerosol size fractions (2.5 and 10 µm) and characterized by culture-dependent (plate-counting) and culture-independent (DNA sequencing) approaches. Studies have revealed a large diversity of bacteria in bioaerosols, highlighting Proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes as ubiquitous phyla. Seasonal variations in and dispersion of bacterial communities have also been observed between geographical locations as has their correlation with specific atmospheric factors. Several investigations have also suggested the relevance of airborne bacteria in the public health and agriculture sectors as well as remediation and atmospheric processes. However, although factors influencing airborne bacterial communities and standardized procedures for their assessment have recently been proposed, the use of bacterial taxa as microbial indicators of specific bioaerosol sources and seasonality have not been broadly explored. Thus, in this review, we summarize and discuss recent advances in the study of airborne bacterial communities in outdoor environments and the possible factors influencing their abundance, diversity, and seasonal variation. Furthermore, airborne bacterial activity and bioprospecting in different fields (e.g., the textile industry, the food industry, medicine, and bioremediation) are discussed. We expect that this review will reveal the relevance and influencing factors of airborne bacteria in outdoor environments as well as stimulate new investigations on the atmospheric microbiome, particularly in areas where air quality is a public concern.