Determination of Some Anions in the Drinking Groundwater Around Tehran in Fall and Winter

Background and Objective: Some anions like nitrate and fluoride are important in health. Nitrate can cause methemoglobinemia in babies and high risk groups.Uptake of excess amounts of fluoride in long-term can contribute to chronic adverse effects. In this study we measured the concentrations of nitrate and fluoride in water of the wells around Tehran and compared it with international standards.Material and Method: Sampling from different wells was carried out in two stages in the fall and winter of 2010 in around Tehran . This study was done after transfering of samples to Institute Pasteur laboratory for analysing. Measurement of nitrate ion was performed using Ion chromatography(Metrohm Company, USA) with standard method. Fluoride level measured in the same way by Ion chromatography. Results: Our study showed that the average fluoride concentration in the fall and winter of 2010 in the wells around Tehran was 0.43 mg/L and 0.32 mg/L respectively. According to this study the level of nitrate in the wells surrounding Tehran was 29.59 mg/L in the fall and 37.27 mg/L in the winter of 2010.Conclusion: This study showed that the average levels of fluoride and nitrate in most samples were within the international standard limits. It also showed that the average concentration of nitrate is higher in the winter and fluoride is higher in the fall.

کلیدواژه ها:

fluoride ، nitrate ، drinking grounwater ، ion exchange ، Tehran