Size-segregated bioaerosols concentration and characterization under diverse microenvironments

Abstract

Scientific research on the concentration and size distribution of bioaerosols in diverse environmental conditions is recently being prioritized. Exposure to bioaerosols, especially through inhalation, is linked to many severe health complications. The inhalation of the bioaerosols is directly linked with the size as well as the nature of the bioaerosols. However, information related to the prevalence of bioaerosols is limited in India, constituting the basis for investigating variations in bacterial and fungal bioaerosol concentrations at various indoor sites. Several observational campaigns were initiated within diverse indoor sites, including cowshed, poultry, canteen, library, auditorium, laboratory, and hospital, using a six-stage viable impactor. Bacterial bioaerosols were more prevalent for size > 7.0 μm and between 1.1 and 2.1 μm. In contrast, fungal concentration peaked in the size range of 1.1 to 3.3 μm. At all the sites, the concentration of bacterial bioaerosols exceeded fungal bioaerosols (2 to 12 times), while such variation was exceptionally high in the poultry firm (70 times higher). No significant correlation was noted between bacterial and fungal bioaerosol concentration and environmental factors. The diversity of bacteria and fungi bioaerosols was found to be different as it varied from site to site. However, species like Acinetobacter and Bacillus sp. in bacteria and Penicillium, Aspergillus, and Cladosporium in fungi were most prevalent. Some of the bioaerosols found in these sites are pathogenic in nature and may cause severe health issues (if found in significant amount). The predominance of bioaerosols is mostly within the breathable range (< 3.3 μm) in diverse microenvironments.