فهرست مطالب ahmadreza yazdanbaksh

Nowadays increasing concentrations of nitrite and nitrate compounds in natural waters, especially underground water resources of large cities, is causing concern. Nitrate has long been considered as a chemical indicator of water pollution. The purpose of this study was to determine nitrite and nitrate levels in drinking water of Tehran provinces covered by the Shahid Beheshti University of Medical Sciences. This descriptive-analytical and cross-sectional study was done to determine nitrite and nitrate levels in drinking water of the respective areas of Tehran. Based on the findings of previous studies, in this study 150 points were randomly selected, sampling was done and then they were measured by a spectrophotometer. The Results indicated that the mean and standard deviation of nitrate are 18.09 mg/l and 22.67 mg/l respectively, from 2.65 to 87.50 mg/l and the mean and standard deviation of nitrite are 24.30 and 52.72 µg/l respectively, from 0 to 300 micrograms per liters. The means of nitrate concentration in many of the samples were less than the WHO standard and the latest standard of Iran for nitrate that is 50 mg/l. However, the protection of groundwater resources against the entry of pollutants, comprehensive studies to monitor the chemical quality of water resources and offer practical programs to accelerate the implementation of wastewater collection and treatment, and preventing the rising of nitrite and nitrate ions, seem necessary.