Association of Nitrate, Nitrite, and Total Organic Carbon (TOC) in Drinking Water and Gastrointestinal Disease

Objective. We aimed to investigate the amounts of nitrate, nitrite, and total organic carbon (TOC) in two drinking water sources and their relationship with some gastrointestinal diseases. Methods. This cross-sectional study was conducted in 2012 in Iran. Two wells located in residential areas were selected for sampling and measuring the TOC, nitrate (NO3？), and nitrite (NO2？). This water is used for drinking as well as for industrial and agricultural consumption. Nitrate and nitrite concentrations of water samples were analyzed using DR 5000 spectrophotometer. The information of patients was collected from the records of the main referral hospital of the region for gastrointestinal diseases. Results. In both areas under study, the mean water nitrate and nitrite concentrations were higher in July than in other months. The mean TOC concentrations in areas 1 and 2 were 2.29 ± 0.012 and 2.03 ± 0.309, respectively. Pollutant concentration and gastrointestinal disease did not show any significant relationship . Conclusion. Although we did not document significant association of nitrite, nitrate, and TOC content of water with gastrointestinal diseases, it should be considered that such health hazards may develop over time, and the quality of water content should be controlled to prevent different diseases. 1. Introduction Nitrate is considered as the most prevalent chemical contaminant in the world’s groundwater. Organic and inorganic sources of nitrogen are converted to nitrate. After reducing, nitrate can be biologically transformed to nitrogen gas. The growing contamination of public and private well drinking water by nitrate is mostly because of the widespread use of commercial fertilizers and waste [1]. Groundwater is used for agricultural and industrial consumption as well as for drinking water. Humans have altered the nitrogen cycle dramatically over the last decades, and as a result, nitrate is increasingly accumulating in water resources. Globally, human nitrogen production has increased significantly since 1950 due to the use of nitrogen fertilizers. In agricultural areas, groundwater and private and low depth wells have higher levels of nitrate. Fertilizers are most important contributing factor in agricultural areas; however, nitrogen from human waste seems to be an essential source in urban areas with deficient centralized water and sanitation systems [2]. Nitrate is in solution form and is mobile. It could become spread in groundwater and is one of the most common pollutant and concern for human health. It may have several health hazards.