title: A low-cost intervention for cleaner drinking water in Karachi, Pakistan.
abstract: OBJECTIVE
  To pilot test an inexpensive, home-based water decontamination and storage system in a low-income neighborhood of Karachi.
  
  
  METHODS
  Fifty households received a 20-L plastic water storage vessel with a high-quality spout and a regular supply of diluted hypochlorite solution. Twenty-five control households were recruited. Water samples were collected at baseline and during unannounced follow-up visits 1, 3, 6, and 10 weeks later.
  
  
  RESULTS
  Baseline drinking water samples among intervention households were contaminated with a mean 9397 colony-forming units (cfu)/100 mL of thermotolerant coliforms compared with a mean 10,990 cfu/100 mL from controls. After intervention the mean concentration of thermotolerant coliforms decreased by 99.8% among the intervention households compared with an 8% reduction among controls. Two years after vessel distribution, 34 (68%) of the families were still using the vessel. Thirteen of the households had stopped using their vessel because it had broken after more than 6 months of use, a pattern most consistent with ultraviolet radiation-induced degradation of the plastic.
  
  
  CONCLUSIONS
  In a highly contaminated environment, a specifically designed water storage container and in-home water chlorination was acceptable and markedly improved water quality. Where plastic water vessels will be exposed to substantial sunlight, ultraviolet light stabilizers should be incorporated into the plastic.
authors.affiliation: Community Health Sciences, Aga Khan University, Karachi, Pakistan. sx12@cdc.gov
authors.forename: S
authors.initials: S
authors.lastname: Luby
authors.forename: M
authors.initials: M
authors.lastname: Agboatwalla
authors.forename: A
authors.initials: A
authors.lastname: Raza
authors.forename: J
authors.initials: J
authors.lastname: Sobel
authors.forename: E
authors.initials: E
authors.lastname: Mintz
authors.forename: K
authors.initials: K
authors.lastname: Baier
authors.forename: M
authors.initials: M
authors.lastname: Rahbar
authors.forename: S
authors.initials: S
authors.lastname: Qureshi
authors.forename: R
authors.initials: R
authors.lastname: Hassan
authors.forename: F
authors.initials: F
authors.lastname: Ghouri
authors.forename: R M
authors.initials: RM
authors.lastname: Hoekstra
authors.forename: E
authors.initials: E
authors.lastname: Gangarosa
mesh_terms: D003365:Costs and Cost Analysis; D003906:Developing Countries; D018508:Water Purification / Q000191:economics*; D014881:Water Supply