title: Chlorination and chloramination of tetracycline antibiotics: disinfection by-products formation and influential factors.
abstract: Formation of disinfection by-products (DBPs) from chlorination and chloramination of tetracycline antibiotics (TCs) was comprehensively investigated. It was demonstrated that a connection existed between the transformation of TCs and the formation of chloroform (CHCl3), carbon tetrachloride (CCl4), dichloroacetonitrile (DCAN) and dichloroacetone (DCAce). Factors evaluated included chlorine (Cl2) and chloramine(NH2Cl) dosage, reaction time, solution pH and disinfection modes. Increased Cl2/NH2Cl dosage and reaction time improved the formation of CHCl3 and DCAce. Formation of DCAN followed an increasing and then decreasing pattern with increasing Cl2 dosage and prolonged reaction time. pH affected DBPs formation differently, with CHCl3 and DCAN decreasing in chlorination, and having maximum concentrations at pH 7 in chloramination. The total concentrations of DBPs obeyed the following order: chlorination>chloramination>pre-chlorination (0.5h)>pre-chlorination (1h)>pre-chlorination (2h).
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China.
authors.forename: Shiqing
authors.initials: S
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China; China Academy of Urban Planning & Design, Beijing 100037, China. Electronic address: yishengshao@163.com.
authors.forename: Yisheng
authors.initials: Y
authors.lastname: Shao
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China.
authors.forename: Naiyun
authors.initials: N
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China.
authors.forename: Shumin
authors.initials: S
authors.lastname: Zhu
authors.affiliation: Shanghai Urban Water Resources Development and Utilization National Engineering Center Co. Ltd., Shanghai 200092, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Ma
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Deng
mesh_terms: D000097:Acetonitriles / Q000138:chemical synthesis; D000900:Anti-Bacterial Agents / Q000737:chemistry*; D002700:Chloramines / Q000737:chemistry*; D002713:Chlorine / Q000737:chemistry*; D004203:Disinfection; D054879:Halogenation; D006863:Hydrogen-Ion Concentration; D013754:Tetracyclines / Q000737:chemistry*
chemical_list: D000097:Acetonitriles; D000900:Anti-Bacterial Agents; D002700:Chloramines; D013754:Tetracyclines; D002713:Chlorine; C030816:chloramine; C051716:dichloroacetonitrile
keywords: Chlorine dosage; Disinfection modes; Reaction time; Tetracycline antibiotics; pH