環境および分析毒性学

Nitrate Content in Drinking Water in Gilan and Mazandaran Provinces, Iran

Abstract

Parisa Ziarati, Tirdad Zendehdel and Sepideh Arbabi Bidgoli

Water pollution issue has become one of the most important public awareness issues. The excessive use of the fertilizers and pesticides in agriculture with the threat of the chemicals in water and crops especially in the two north provinces of Iran is a major concern of Iranian environmental scientists. This project is a trial to find out the status of nitrate content in drinking water of two great provinces in the north of Iran. The objectives of the present research: Determination the level of nitrate (mg/L) in drinking water of some agricultural and industrial cities and comparing of the probable effects of different industrial factories on the level of nitrate in drinking water of them. The tap water samples of 60 different sites from Rasht , Bandar Anzali and Talesh in Gilan province and Sari, Behshar and Amol in Mazandaran province in three consequent months in summer season (July, August and September) in 2013, were collected and by spectroscopy method were determined. There are no wastewater collection, treatment and disposal system in these cities. Sampling was replicated twice within each month at intervals of two weeks and the mean value considered as a result of one sample. To evaluate variability of nitrate content within sub-samples, five sub-samples (900 sub-samples) on the whole were analyzed separately. The mean concentrations of NO3- (mg/L) in most examined water samples were lower than acceptable ranges (NO3- ≤ 50 (mg/L) and only 11% of all samples were higher than it. A highly significant, positive correlation was found between nitrate contents of the August and September drinking water samples , compared to July ones. Results shows a significant difference between locations (p<0.03) and in the different sites as nitrate content in drinking water in industrial locations were obviously higher than other locations in the cities.