Quality assessment of drinking water in Temeke District (part II): Characterization of chemical parameters

This paper presents a study on drinking water quality in Temeke District (Dar es Salaam), which involved analyses of chemical parameters of drinking water samples from different drinking water sources. The drinking water sources examined included tap water, river water and well water (deep and shallow wells). Water quality studied includes pH, chloride, nitrate and total hardness levels. The concentrations of total hardness in mg CaCO3/L and chloride were obtained by titration method while the nitrate concentration levels were determined by spectrophotometer. Tap water was found to be of high quality than other sources in terms of chemical characteristics. The study revealed that the chemical parameters of water sources did not meet the permissible World Health Organization (WHO) and Tanzania Bureau of Standards (TBS) levels. Examining exceedence above the WHO standards, it was revealed that most of the samples contained chloride levels above allowable WHO limits. It was recommended that drinking water sources for domestic use should be protected from pollution sources.Key words: Drinking water quality, pH, chloride, nitrates, total hardness, exceedence

Water Quality Index for measuring drinking water quality in rural Bangladesh: a cross-sectional study

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