TY - JOUR T1 - Survey the THMs Value in Drinking Water in Lahijan and Suggestions in Order to Product Control after Disinfection TT - بررسی مقدار ترکیب‌های سرطان‌زای تری‌هالومتان در آب آشامیدنی شهر لاهیجان و پیشنهاد کنترل پیش‌سازهای محصول جانبی گندزدائی JF - gums-med JO - gums-med VL - 17 IS - 68 UR - http://journal.gums.ac.ir/article-1-273-en.html Y1 - 2009 SP - 1 EP - 6 KW - Chlorine KW - Disinfections KW - Trihalomethanes KW - Water N2 - Abstract Introduction: Considering the surface water resource as one of the main potable water supplies and the application of chlorine as one of the main disinfectant drinking water has increased the rate of Disinfection By-Products (DBPs) formation. One of the main group of DBPs are THMs compounds that the studies showed they have the potential of increasing the rate of kidney, liver adverse effects and are carcinogen compounds. Objective: Survey the THMs concentration in lahijan drinking water and relation between THMs formation with temperature, pH, free residual chlorine and Total Organic Carbon (TOC). Materials and Methods: In this study, five locations in four steps were selected for sampling two points in sangar water treatment plant (SWTP) include: raw water and treated water and three points in lahijan distribution system include: before and after of chlorination unit and in termination of distributed water, where samples collected in winter (9 samples) and summer (7 sample) and then analyzed by the GC set with EC detector. Results: This study show that the THMs concentration in raw water and treated water in SWTP was normal and THMs concentration in treated water was less than raw water that showed effective efficiency of treatment plant units. THMs concentration in before of chlorination unit was normal and in after of this unit and termination of distributed water was more than US.EPA standard. This study showed a positive relation between THMs formation with temperature, pH, free residual chlorine and TOC. Minimum and maximum concentration of THMs compound was seen in treated water of SWTP and in termination of lahijan distributed water, respectively, that show the relation between exposure time and DBPs formation. Conclusion: Regarding to high statistic of digestive cancers in Guilan, epidemiological studies showed effective agents about this cancers including: genetic agents and usage of salty foods. But, high concentration of THMs in total samples in lahijan distributed water could be an effective agent in increase of statistic digestive cancers in lahijan. M3 ER -