Characterization of bioaerosols in Northeast India in terms of culturable biological entities along with inhalable, thoracic and alveolar particles

Effort was made to analyse the biological components along with inhalable, thoracic and alveolic particles
in aerosol samples collected from nine distinct locations of Northeast India during post-monsoon season
(October–November) for the very Brst time. Microscopic analysis reveals the presence of 70–90% of non
biological particles followed respectively by pollens (9–18%), animal debris (1–12%) and fungal spores
(1–6%). The concentration of bacteria in air sample ranges from 45.5 to 645.84 CFU/m3. All the bacterial
isolates showed sensitivity against broad (Chloramphenicol and Ampicillin) and narrow (Vancomycin
and Erythromycin) spectrum antibiotics which indicates lesser threat to human health. Moreover, the
concentration of microbial content in the bioaerosol samples are less compared to some of the reported
values in other parts of India. The predominant microbial genera in the collected bioaerosol samples were
identiBed as Gram positive Diplobacilli sp. followed by Diplococci sp. Pollens of 10–20 lm diameter,
which are mostly considered as potential allergens, contribute only up to 20% of total pollen content in
the bioaerosol sample collected from various locations indicating healthier air.