Survey of chemical quality (Nitrate, Flouride, Hardness, Electrical Conductivity) of driking water in Khoy city

Water quality has directly related to personal and public health. Therefore monitoring of water supplies and theirs sanitary conditions is very important. The aim of this study was to investigate the chemical quality of drinking water in Khoy city (West Azarbaijan province، Iran) during 2008 and 2009. This resach was a descriptive study. All data of water quality was received from Water and Wastewater Co in Western Azerbaijan province. Collected data was for 24 months from March 2008 to February 2009. The data were analyzed by using Spss and Excel software and then compared with the national standards. the results showed that the mean concentration of nitrate was18. 9 ± 9. 4 mg / l during two years. The mean concentration of EC was 589 ±120µs/cm in the all studied wells. The mean concentration of fluoride was 0. 39 ± 0. 1 mg /l. The average hardness of water was 293 ±64 mg/l as calcium carbonate. Although the electrical conductivity and nitrate concentrations in Khoy city drinking water were lower than the standard values، the concentration had the increasing trend in two years consequently. According to average annual temperature of weather in the region، the fluoride content is lower than the standard value in all wells. The drinking water of Khoy city is calssifed in hard and very hard categories. The relation between hardness and electrical conductivity is a direct linear ratio.