investigating the chemical quality and chlorination status of drinking water in kashan’s villages

background: according to the health world organization drinking water must be free of chemicals and microbial contaminations which are risk to human health. therefore water quality control is very important. the purpose of this study is investigating the chemical quality and chlorination status of drinking water in kashan’s villages. methods: this cross-sectional study was conducted on drinking water in kashan’s villages in the second-half of 2007. in this study, the physicochemical parameters of the water resources and free chlorine residue of the water in delivery points were measured for one and three times respectively. findings: the findings of this study indicated that in all villages the densities of nitrate, nitrite, chloride, calcium, and ph were within the standard limit. but the density of sulfate, magnesium, sodium, tds, and turbidity were respectively at 5.3%, 5.3%, 8.8%, 5.3%, and 3.5% which are higher than the standard limits, and fluoride density at 50.9% is lower than the maximum contaminant levels. also in view of free chlorine residue, 40.0% of under coverage rural population, 1.5% of non-covered population by kashan rural water and wastewater company (krwwc), and 34.8% of the whole population of kashan’s villages use desirable quality water. conclusion: based on the findings of this study, it can be expressed that the mean density of most chemical parameters in kashan’ villages drinking water is within the 1053 standard limit  in iran, but the fluoride density is lower than the maximum contaminant levels in many villages. also, the desirability index of free chlorine residue of drinking water in kashan’s villages is lower than countrywide average.