title: An ignored and potential source of taste and odor (T&O) issues-biofilms in drinking water distribution system (DWDS).
abstract: It is important for water utilities to provide esthetically acceptable drinking water to the public, because our consumers always initially judge the quality of the tap water by its color, taste, and odor (T&O). Microorganisms in drinking water contribute largely to T&O production and drinking water distribution systems (DWDS) are known to harbor biofilms and microorganisms in bulk water, even in the presence of a disinfectant. These microbes include T&O-causing bacteria, fungi, and algae, which may lead to unwanted effects on the organoleptic quality of distributed water. Importantly, the understanding of types of these microbes and their T&O compound-producing mechanisms is needed to prevent T&O formation during drinking water distribution. Additionally, new disinfection strategies and operation methods of DWDS are also needed for better control of T&O problems in drinking water. This review covers: (1) the microbial species which can produce T&O compounds in DWDS; (2) typical T&O compounds in DWDS and their formation mechanisms by microorganisms; (3) several common factors in DWDS which can influence the growth and T&O generation of microbes; and (4) several strategies to control biofilm and T&O compound formation in DWDS. At the end of this review, recommendations were given based on the conclusion of this review.
authors.affiliation: College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
authors.forename: Xinyan
authors.initials: X
authors.lastname: Zhou
authors.affiliation: College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, Zhejiang, 310058, China. zhangkj@zju.edu.cn.|Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province, Hangzhou, Zhejiang, 310058, China. zhangkj@zju.edu.cn.
authors.forename: Kejia
authors.initials: K
authors.lastname: Zhang
authors.affiliation: College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, Zhejiang, 310058, China. ztq@zju.edu.cn.|Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province, Hangzhou, Zhejiang, 310058, China. ztq@zju.edu.cn.
authors.forename: Tuqiao
authors.initials: T
authors.lastname: Zhang
authors.affiliation: College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, Zhejiang, 310058, China.|Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province, Hangzhou, Zhejiang, 310058, China.
authors.forename: Cong
authors.initials: C
authors.lastname: Li
authors.affiliation: College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
authors.forename: Xinwei
authors.initials: X
authors.lastname: Mao
mesh_terms: D001419:Bacteria / Q000254:growth & development / Q000378:metabolism; D018441:Biofilms / Q000254:growth & development*; D004203:Disinfection / Q000379:methods; D060766:Drinking Water / Q000382:microbiology*; D005421:Flavoring Agents / Q000378:metabolism*; D005658:Fungi / Q000254:growth & development / Q000378:metabolism; D058086:Microalgae / Q000254:growth & development / Q000378:metabolism; D009812:Odorants; D013649:Taste
chemical_list: D060766:Drinking Water; D005421:Flavoring Agents
keywords: Control methods; Drinking water distribution systems; Mechanisms; Microorganisms; Taste and odor