Microbiological Pollution of Air in Lal Bagh Botanical Gardens, Bangalore, Karnataka, India

Bioaerosols significantly influence indoor and outdoor air quality and may cause numerous allergies and diseases. Intensity of habitual birds within the park and recreational garden exposes the visitors to elevated concentrations of bioaerosols that is mainly emitted by birds. Our study presents results of an evaluation of air quality in the Lal Bagh Botanical Garden in Bangalore. Air tests were conducted by using of impaction method at different sites of the garden and compared with Outdoor Air quality standards prescribed by Polish- European Environmental protection agency PN-89/Z-04111/02 and PN-89/Z-04111/03. The analysis indicates that bacterial pollution were the most abundant at Pigeon feeding/sheltering site and the bacterial number increased with distance of downwind. Negative rods dominated making up 45% and positive Cocci were 36% of the airborne bacterial community. Negative coccus was recorded as 13% and positive rod was recorded as 6%. Eight species of bacteria detected are Aeromonas sp., Enterococcus faecalis, Mycobacterium sp., Citrobacter sp., Pseudomonas sp., E.coli, Micrococcus, Staphylococcus sp. These pathogens may get aerosolized from Pigeon faecal matter and drops. The most abundant microorganisms in this region were fungi, the concentration of fungal number varied from 2,805 to 3,451 CFU/m3, predominating genera were Aspergillus, Fusarium and Alternaria contributed over 17%,15%,15% of all fungal genera. These fungal genera are strongly associated with asthma and other respiratory diseases which may get aerosolized from trees and thick vegetation in the garden. The overall microbial study revealed that Lal Bagh garden is moderately polluted according to the norms of the Polish- European Environmental protection agency. The high intensity of Pigeon population in the garden contributing bacterial and fungal pollution in the air and drives risk of health impacts on visitors.