title: Exploring the biological stability situation of a full scale water distribution system in south China by three biological stability evaluation methods.
abstract: Bacterial regrowth especially opportunistic pathogens regrowth and contamination in drinking water distribution systems (DWDS) have become an emerging threat to public health in the whole world. To explore bacterial regrowth and biological stability, assimilable organic carbon (AOC), biodegradable dissolved organic carbon (BDOC) and bacterial regrowth potential (BRP) were evaluated in a full scale DWDS and bench tests in South China. A significant correlation between BRP and AOC in both water treatment processes (WTP) and DWDS was obtained. For BRP and BDOC, the correlation was more significant in WTP than in DWDS. Both AOC and BRP were significantly correlated with UV254, total organic carbon (TOC), and heterotrophic plate count (HPC) (p < 0.01), whereas BDOC was only significantly associated with UV254, temperature and chlorine residual (p < 0.01). Through a bench test, when chlorine was higher than 0.5 mg/L, the HPC level was low and AOC concentration almost unchanged. On contrary the HPC level increased quickly and declined slightly, with chlorine lower than 0.15 mg/L, which was in accordance with the large amount of biological stability data obtained from DWDS. Through another bench test, the HPC level was positively correlated to AOC concentration and when AOC was below 135 μg/L, the growth rate of HPC was low, which was verified by the analysis of biological stability data from DWDS.
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China.
authors.forename: Junpeng
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Yangtze Aquatic Environment, Ministry of Education College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. Electronic address: 123lwyktz@tongji.edu.cn.
authors.forename: Wei-Ying
authors.initials: WY
authors.lastname: Li
authors.affiliation: College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.affiliation: College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Qian
authors.affiliation: College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Xu
authors.affiliation: College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Liu
authors.affiliation: College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
authors.forename: Wanqi
authors.initials: W
authors.lastname: Qi
mesh_terms: D001419:Bacteria / Q000254:growth & development*; D002244:Carbon / Q000032:analysis*; D002681:China; D002713:Chlorine / Q000032:analysis; D004203:Disinfection; D060766:Drinking Water / Q000032:analysis / Q000737:chemistry / Q000382:microbiology; D009930:Organic Chemicals / Q000032:analysis*; D014871:Water Microbiology / Q000592:standards*; D018508:Water Purification / Q000379:methods*; D014881:Water Supply / Q000379:methods*
chemical_list: D060766:Drinking Water; D009930:Organic Chemicals; D002713:Chlorine; D002244:Carbon
keywords: Assimilable organic carbon (AOC); Bacterial regrowth potential (BRP); Biodegradable dissolved organic carbon (BDOC); Biological stability evaluation; Disinfectant effect; Full scale water distribution systems