بررسی غلظت کلروفرم در آب شرب تهران در سال 1388

Background and purpose: Chloroform is a disinfection byproducts (DBPs) that results from reactions between residual chlorine and organic compounds as precursors. The presence of these DBPs in chlorinated drinking water can pose a severe public health threat including potential carcinogenicity. In this study chloroform concentrations as an indicator of DBPs of chlorinated water was evaluated in Tehran’s drinking water system. Material and Methods: This study was a cross-sectional study in which the samples were taken from water treatment outlet and from certain points of the water distribution network in different seasons during 2009. The samples were analyzed for presence of chloroform compounds using standard methods. The temperature, pH, and residual chlorine concentration were measured as the most important factors associated with chloroform concentrations. Results: Total average concentrations of chloroform in the water treatment plant outlet and in the distribution network were 11.2 and 36.5 micrograms per liter, respectively. These amounts in distribution network concentrations were almost 3.3 times more than the amount of water treatment outlet concentrations. Conclusion: Evaluation of chloroform concentrations in the water treatment plant outlet and distribution network involving temperature, pH, and chlorine residual indicated a direct correlation between them, which was significant in distribution network system and non-significant in the water treatment plant.