Monitoring, Analyzing and Human Health Risk Assessment Produces Disinfection By-Products in Tabriz Drinking Water Network

Document Type : Research Paper


1 MSc. Student, Faculty of Environment, University of Tehran, Tehran, Iran

2 PhD. Student, Faculty of Environment, University of Tehran, Tehran, Iran


Chlorine has the high oxidation power of natural organic matter in water. Chlorine injection produces disinfection by-products as carcinogens and more dangerous (THMs). We used descriptive and hierarchical analysis to understand the characteristics and dangerous factors affecting human health in the face of DBPs in the drinking water of Tabriz City. This research was done in order to provide key and strategic information to perform managerial and practical measures to reduce the risk of cancer and non-cancer. Monitoring and analysis was done by collecting sufficient samples of this research in the dry and wet seasons of the year, focused on the relative factors of the population density of the region and the topography of the urban fabric for functional and management zoning of drinking water distribution network in Tabriz City; Also, by reading some physical and chemical parameters at the sampling site. Samples were transferred to the laboratory in the shortest possible time and samples were prepared and trihalomethane compounds were measured by gas chromatography and mass spectrometer detector. The results showed that the highest average concentration in the Urban network, belongs to the region where a higher percentage of surface water is supplied, which is chloroform 1.3049 ppb, bromoform 2.0961 ppb, bromodichloromethane 2.7713 ppb and dibromochloromethane 4.1891 ppb, which is still less than the guidelines stated by the National Standard of Iran and USEPA and WHO. Conclusion: The results were divided into several subgroups in terms of dry or wet season, different urban areas, surface water or underground water as a source to evaluate the risk of human health. In addition, we also estimated population health risks by gender and age. In the time division, the health risk from exposure to DBPs in drinking water in the wet season was 7.3% higher than the dry season. The total cancer risk for people living in the area all their life was 7.63E-06. Also, the non-carcinogenic hazard index (HI=3.43E-02<1). It shows that there is no health risk in the present situation. In the age and gender division, the health risk assessment of men exposed to DBPs compared to women was equalized as an adult group. But there were differences between different age subgroups. The risk of developing cancer in children was 52% higher than in adults.


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