Biological Aerosol Particles in Polluted Regions

PURPOSE OF REVIEW: Biological aerosol particles play a crucial role in the Earth system, particularly in the land/ocean-atmosphere interactions. This paper aims to summarize the up-to-date research progresses on the characteristics, biomarkers as well as the health-related, climatic and ecological effects of biological aerosol particles in polluted regions, especially in East Asia and South Asia. RECENT FINDINGS: The atmospheric abundance, size distribution, and community structure of microorganisms show differences during haze and non-haze conditions. The long-distance transportation of dust-associated microorganisms influences the abundance and community structure of airborne microbes in downwind areas. Wildfire smoke or biomass burning potentially impacts the release, transport and dispersal of microorganisms in the atmosphere. Meteorological conditions and air pollutants likely interact with airborne microorganisms, pollen, and fluorescent biological aerosol particles. Molecular biomarkers including proteins and amino acids, sugars, and lipid compounds have been used to fingerprint the sources of biological aerosols and give important biogeochemical information of atmospheric aerosols. In addition to pathogenic and allergenic microorganisms and pollen, biological aerosol particles indicated by abundant endotoxins and antibiotic resistance genes could have significant impacts on public health. In polluted regions, the potential influences of biological aerosol particles on climate and ecosystems could be more complex. We comprehensively summarize the recent research progresses on the characteristics, biomarkers, influencing factors, and effects of biological aerosol particles in polluted regions, mostly in East Asia and South Asia. To further understand the complicated effects of biological aerosol particles in polluted regions, the development and application of novel approaches and techniques as well as in-depth investigations on the roles of biological aerosol particles in atmospheric chemistry, cloud formation, and public health need to be implemented.