Survey of the effective factors in the production of HAAs and measuring their concentration in the Tehran outlet water treatment plants in the first half of 2010

Chlorination is the most common method of water disinfection. Chlorine reaction with natural organic compounds nor removed completely during treatment process would result in forming disinfection byproducts. Followed by trihalomethanes، Haloaceticacides are the second main byproducts of chlorination in water. The research works conducted in Iran have assessed trihalomethanes. Hence، this is the first time we are reporting haloacetic acids in Iran. Materials and We collected samples from surface water resources and treated water in Tehran for six consecutive months (first half، 2010). We measured temperature، pH، UV adsorption at 254 nm and TOC in each surface water sample and analyzed pH، residual chlorine، and haloacetic acids in the treated water samples. We found that TOC in surface water resources is 3. 6-4. 42 and 1. 78-2. 71 mg/l in spring and summer respectively. Moreover، haloacetic acids concentration was found to be 41. 7-55. 56 and 34. 83-43. 73 μg/l in spring and summer respectively. Our results revealed that concentration of NOM، TOC، and HAAs was more in spring than summer. In addition، concentration of HAAs was depended up on NOM and TOC. Considering maximum permeable concentration of HAAs (60 μg/l) by EPA، it can be claimed that concentration of HAAs was less than the maximum permissible level in all of the samples. However، the immanency of the monitored values to the standard values can be a warning for concerned authorities in water industry.