Health Risk Assessment of Microbial Water Quality and Bioaerosols Emission from Byramangala Reservior, Karnataka, India

Bioaerosol emissions surrounding waste water treatment plants, polluted lakes and rivers are a health risk concern in humans. Dumping of human and animal wastes in the lake and river is the main reason for the bioaerosols emitted into the ambient air. The microorganisms in the air studied using an Anderson microbial air sampler. Microorganisms like E. coli and Fecal streptococci in water samples collected from Byramangala reservoir was estimated to be an average of 1, 685 CFU/100ml and 1, 648 CFU/100ml. Enterobacter allergens were estimated around 1, 292 CFU/100ml and Staphylococcus aureus was 892CFU/100ml. Bioaerosols from outlet weir were enumerated and compared with upwind and downwind. The bioaerosols number was varied with distance of downwind. Intestinal pathogens like Fecal coliform aerosolized at outlet weir and population were ranged from 348 CFU/m3 to 1372 CFU/m3. Similarly, fecal streptococcus number ranged from 45 CFU/m3 to 275 CFU/m3. Salmonella sp. , ranged from 95 CFU/m3 to 322 CFU/m3. Bacteriological analysis of a water samples reveals that Byramangala lake is polluted with E. coli and other coliform bacteria which has crossed the permissible limit prescribed by WHO, 1989 for wastewater irrigation and reuse. Microbial contamination beyond the permissible limit which is health risk for farmers who are irrigating the lake water for their farm. Bioaerosol studies around the lake indicates that the presence of bacterial pollution in the ambient air driven by Enterobacteriacae members such as E-coli, fecal streptococcus and salmonella sp in lake water which has got aerosolized with the influence of foam and gets transported by ground level turbulence. The formation of stable foams at outlet weir and irrigation canal proves that the water body receives phosphate and oil based pollutants from domestic sewage and industrial effluent. The continuous flow of raw sewage and industrial effluent worsening the lake water quality and deteriorate the air quality of settlements around the Byramangala reservoir.