title: Water Quality Index for measuring drinking water quality in rural Bangladesh: a cross-sectional study.
abstract: BACKGROUND
  Public health is at risk due to chemical contaminants in drinking water which may have immediate health consequences. Drinking water sources are susceptible to pollutants depending on geological conditions and agricultural, industrial, and other man-made activities. Ensuring the safety of drinking water is, therefore, a growing problem. To assess drinking water quality, we measured multiple chemical parameters in drinking water samples from across Bangladesh with the aim of improving public health interventions.
  
  
  METHODS
  In this cross-sectional study conducted in 24 randomly selected upazilas, arsenic was measured in drinking water in the field using an arsenic testing kit and a sub-sample was validated in the laboratory. Water samples were collected to test water pH in the laboratory as well as a sub-sample of collected drinking water was tested for water pH using a portable pH meter. For laboratory testing of other chemical parameters, iron, manganese, and salinity, drinking water samples were collected from 12 out of 24 upazilas.
  
  
  RESULTS
  Drinking water at sample sites was slightly alkaline (pH 7.4 ± 0.4) but within acceptable limits. Manganese concentrations varied from 0.1 to 5.5 mg/L with a median value of 0.2 mg/L. The median iron concentrations in water exceeded WHO standards (0.3 mg/L) at most of the sample sites and exceeded Bangladesh standards (1.0 mg/L) at a few sample sites. Salinity was relatively higher in coastal districts. After laboratory confirmation, arsenic concentrations were found higher in Shibchar (Madaripur) and Alfadanga (Faridpur) compared to other sample sites exceeding WHO standard (0.01 mg/L). Of the total sampling sites, 33 % had good-quality water for drinking based on the Water Quality Index (WQI). However, the majority of the households (67 %) used poor-quality drinking water.
  
  
  CONCLUSIONS
  Higher values of iron, manganese, and arsenic reduced drinking water quality. Awareness raising on chemical contents in drinking water at household level is required to improve public health.
authors: BRAC Research and Evaluation Division, BRAC Centre, 75 Mohakhali, Dhaka, 1212, Bangladesh. Tahera.a@brac.net.
authors: Tahera
authors: T
authors: Akter
authors: BRAC Research and Evaluation Division, BRAC Centre, 75 Mohakhali, Dhaka, 1212, Bangladesh. fatema.jhohura@brac.net.
authors: Fatema Tuz
authors: FT
authors: Jhohura
authors: BRAC Research and Evaluation Division, BRAC Centre, 75 Mohakhali, Dhaka, 1212, Bangladesh. fahmida.akter@brac.net.
authors: Fahmida
authors: F
authors: Akter
authors: BRAC Research and Evaluation Division, BRAC Centre, 75 Mohakhali, Dhaka, 1212, Bangladesh. tridib.rc@brac.net.
authors: Tridib Roy
authors: TR
authors: Chowdhury
authors: BRAC Research and Evaluation Division, BRAC Centre, 75 Mohakhali, Dhaka, 1212, Bangladesh. sabuj.km@brac.net.
authors: Sabuj Kanti
authors: SK
authors: Mistry
authors: BRAC Water, Sanitation and Hygiene Programme, BRAC Centre, 75 Mohakhali, Dhaka, 1212, Bangladesh. digbijoy.de@brac.net.
authors: Digbijoy
authors: D
authors: Dey
authors: BRAC Water, Sanitation and Hygiene Programme, BRAC Centre, 75 Mohakhali, Dhaka, 1212, Bangladesh. milan.kb@brac.net.
authors: Milan Kanti
authors: MK
authors: Barua
authors: BRAC Tuberculosis Programme, BRAC Centre, 75 Mohakhali, Dhaka, 1212, Bangladesh. akramul.mi@brac.net.|BRAC Water, Sanitation and Hygiene Programme, BRAC Centre, 75 Mohakhali, Dhaka, 1212, Bangladesh. akramul.mi@brac.net.
authors: Md Akramul
authors: MA
authors: Islam
authors: BRAC Research and Evaluation Division, BRAC Centre, 75 Mohakhali, Dhaka, 1212, Bangladesh. mahfuzar.rahman@brac.net.
authors: Mahfuzar
authors: M
authors: Rahman
mesh_terms: D000465:Algorithms; D001151:Arsenic / Q000032:analysis*; D001459:Bangladesh; D003430:Cross-Sectional Studies; D060766:Drinking Water / Q000737:chemistry* / Q000592:standards; D005191:Family Characteristics; D017408:Guidelines as Topic; D006306:Health Surveys; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000032:analysis*; D008345:Manganese / Q000032:analysis*; D012423:Rural Health; D054712:Salinity; D014874:Water Pollutants, Chemical / Q000032:analysis*; D060753:Water Quality / Q000592:standards; D014944:World Health Organization
chemical_list: D060766:Drinking Water; D014874:Water Pollutants, Chemical; D008345:Manganese; D007501:Iron; D001151:Arsenic