Qi Wang, Fang Yee Lim, Jiangyong Hu
Department of Civil and Environmental Engineering, National University of Singapore, Block E1A, #07-03, No. 1 Engineering Drive 2, Singapore 117576 E-mail:
J Water Health. 2014 Dec;12(4):736-46. doi: 10.2166/wh.2014.117.
The presence of organic compounds in water sources is one of the concerns in water treatment. They are potential precursors of disinfection byproducts (DBPs) and thus induce health problems in humans. Among the emerging DBPs, carcinogenic compound N-nitrosodimethylamine (NDMA) has been receiving attention during the last decade. This study examined the characteristics of organic components in various water sources and investigated their relationships with NDMA formation. Experiments were carried out on selected water samples from both natural water and wastewater. Results showed similar NDMA formation kinetics for both water sources. However, more contribution of NDMA precursors was found to be from the wastewater due to its higher organic nitrogen content. NDMA formation potential (NDMAFP) of secondary effluent ranged from 264 to 530 ng/L. A correlation study between organic compound characteristics and NDMAFP indicated that the majority of NDMA precursors came from dissolved organic nitrogen (DON) compound with small molecular weight (smaller than 500 Da), with correlation R(2) = 0.898. Although secondary treatment removed more than 90% of NDMA precursors, the remaining precursors in secondary effluent would still pose a challenge for water quality.
水源中有机化合物的存在是水处理过程中令人担忧的问题之一。它们是消毒副产物（DBPs）的潜在前体，从而引发人类健康问题。在新兴的消毒副产物中，致癌化合物N-亚硝基二甲胺（NDMA）在过去十年中一直受到关注。本研究考察了各种水源中有机成分的特性，并研究了它们与NDMA形成的关系。对取自天然水和废水的选定水样进行了实验。结果表明，两种水源的NDMA形成动力学相似。然而，由于废水的有机氮含量较高，发现NDMA前体更多地来自废水。二级出水的NDMA形成潜力（NDMAFP）范围为264至530 ng/L。有机化合物特性与NDMAFP之间的相关性研究表明，大多数NDMA前体来自分子量较小（小于500 Da）的溶解有机氮（DON）化合物，相关系数R² = 0.898。尽管二级处理去除了超过9０%的NDMA前体，但二级出水中剩余的前体仍会对水质构成挑战。
