Concentration of Nitrate in Bottled Drinking Water in Qom, Iran

Background & Aims of the Study: Consumption of bottled water in the world is increasing. The highest growth rates are occurring in Asia and South America. Biological and chemical monitoring of these waters is necessary. The aim of current study was determination of nitrate concentration in bottled drinking water in Qom, Iran in 2012. Materials & Methods: A cross-sectional study carried out in Qom, Iran. First of all, 18 most frequent brands of bottled drinking waters were purchased in June 2012 randomly. Then concentration of nitrate was measured according to the spectrophotometric method. In next step, experiment data were analyzed by Excel Software and Pvalue was obtained by statistical calculations. Finally data were comprised with written nitrate concentration on labels and recommended permissible values. Results: The median nitrate concentration was 2.1 mg/L with the minimum 0.8 mg/L and maximum 8.1 mg/L. In 66.7 % of the samples, the measured nitrate concentrations were less than the written nitrate concentrations and in 33.3% of samples, the nitrate concentration was higher. The statistical calculation proved the significant difference between the median of written nitrate concentration on the label and investigated nitrate concentration (Pvalue > 0.05). Conclusions: It be concluded that the measured nitrate concentration in all of the water samples is below the recommended permissible level.