title: Emission of bacterial bioaerosols from a composting facility in Maharashtra, India.
abstract: This study was undertaken to quantify and characterize size-segregated bacterial bioaerosols both on-site and off-site of a waste treatment facility (WTF) in Maharashtra employing windrow composting. Viable bacterial bioaerosols on nutrient agar (NA) and actinomycetes isolation agar (AIA) were quantified after sampling using Anderson-six stage impactor. Viable bacterial bioaerosols were identified based on 16S rDNA sequencing. Approximately, 16-34% of the total viable bacteria collected at the WTF were in the size range 0.65-2.1μm that can penetrate deep into the respiratory tract and also represents bacteria present in free form. Thus, 66-84% of bacterial bioaerosols were associated with coarse airborne particles greater than 2.1μm. A total of 24 bacterial species were isolated and characterized through gram staining. Among these 25% were gram negative and 75% were gram positive. The predominant bacterial genera were Bacillus, Streptococcus, Staphylococcus, Acinetobacter and Kocuria. The mean on-site concentration of total viable bacteria on NA and AIA and airborne particles (PM2.5 and PM10) were higher than the corresponding off-site values. The mean on-site concentration of viable bacteria on NA and AIA were in the range of 3.8×10(3) to 5.4×10(4)CFU/m(3) and 9.8×10(3) to 1.2×10(5)CFU/m(3), respectively, during activity period. Good correlation (R(2)=0.999) was observed between total bioaerosols and aerosols (PM10) collected using Anderson impactor and High volume sampler, respectively. Sampling size segregated aerosols using the Siotus personal cascade impactor indicated higher association of bacteria with the coarse fraction (greater than 2.5μm).
authors.affiliation: Centre for Environmental Science and Engineering, Indian Institute of Technology Bombay, Powai, Maharastra 400076, India.
authors.forename: Arnab Kumar
authors.initials: AK
authors.lastname: Pahari
authors.affiliation: Centre for Environmental Science and Engineering, Indian Institute of Technology Bombay, Powai, Maharastra 400076, India.
authors.forename: Debdeep
authors.initials: D
authors.lastname: Dasgupta
authors.affiliation: Centre for Environmental Science and Engineering, Indian Institute of Technology Bombay, Powai, Maharastra 400076, India.
authors.forename: Rashmi S
authors.initials: RS
authors.lastname: Patil
authors.affiliation: Centre for Environmental Science and Engineering, Indian Institute of Technology Bombay, Powai, Maharastra 400076, India. Electronic address: mitras@iitb.ac.in.
authors.forename: Suparna
authors.initials: S
authors.lastname: Mukherji
mesh_terms: D000336:Aerosols / Q000032:analysis*; D000393:Air Pollutants / Q000032:analysis*; D001419:Bacteria; D000076282:Composting / Q000379:methods* / Q000706:statistics & numerical data; D004784:Environmental Monitoring; D007194:India
chemical_list: D000336:Aerosols; D000393:Air Pollutants
keywords: 16S rDNA; Bacteria; Bioaerosols; Municipal solid waste treatment; PCR