title: The impact of rainfall and seasonal variability on the removal of bacteria by a point-of-use drinking water treatment intervention in Chennai, India.
abstract: Point-of-use water treatment has received widespread application in the developing world to help mitigate waterborne infectious disease. This study examines the efficacy of a combined filter and chemical disinfection technology in removing bacterial contaminants, and more specifically changes in its performance resulting from seasonal weather variability. During a 12-month field trial in Chennai, India, mean log-reductions were 1.51 for E. coli and 1.67 for total coliforms, and the highest concentration of indicator bacteria in treated water samples were found during the monsoon season. Analysis of variance revealed significant differences in the microbial load of indicator organisms (coliforms and E. coli) between seasons, storage time since treatment (TST), and samples with and without chlorine residuals. Findings indicate that the bacteriological quality of drinking water treated in the home is determined by a complex interaction of environmental and sociological conditions. Moreover, while the effect of disinfection was independent of season, the impact of storage TST on water quality was found to be seasonally dependent.
authors.affiliation: a School of Engineering , University of Guelph , Guelph , Canada.
authors.forename: Morgan C
authors.initials: MC
authors.lastname: MacDonald
authors.affiliation: b Department of Geography and Virginia Water Resources Research Center , Virginia Tech , Blacksburg , VA , USA.
authors.forename: Luke
authors.initials: L
authors.lastname: Juran
authors.affiliation: c Department of Civil Engineering , Indian Institute of Technology Madras , Chennai , India.
authors.forename: Jincy
authors.initials: J
authors.lastname: Jose
authors.affiliation: c Department of Civil Engineering , Indian Institute of Technology Madras , Chennai , India.
authors.forename: Sekar
authors.initials: S
authors.lastname: Srinivasan
authors.affiliation: a School of Engineering , University of Guelph , Guelph , Canada.
authors.forename: Syed I
authors.initials: SI
authors.lastname: Ali
authors.affiliation: d Department of Public Health Sciences , Queen's University , Kingston , ON , Canada.
authors.forename: Kristan J
authors.initials: KJ
authors.lastname: Aronson
authors.affiliation: a School of Engineering , University of Guelph , Guelph , Canada.
authors.forename: Kevin
authors.initials: K
authors.lastname: Hall
mesh_terms: D004202:Disinfectants / Q000494:pharmacology*; D004203:Disinfection / Q000295:instrumentation; D060766:Drinking Water / Q000382:microbiology*; D004755:Enterobacteriaceae / Q000187:drug effects / Q000302:isolation & purification*; D004926:Escherichia coli / Q000302:isolation & purification; D007194:India; D011891:Rain; D012621:Seasons; D013607:Tablets; D014227:Triazines / Q000494:pharmacology*; D018508:Water Purification / Q000295:instrumentation
chemical_list: D004202:Disinfectants; D060766:Drinking Water; D013607:Tablets; D014227:Triazines; C011765:troclosene
keywords: India; bacteria; point-of-use; seasonal variability; water treatment