title: Dissolved organic nitrogen and its biodegradable portion in a water treatment plant with ozone oxidation.
abstract: Biodegradability of dissolved organic nitrogen (DON) has been studied in wastewater, freshwater and marine water but not in drinking water. Presence of biodegradable DON (BDON) in water prior to and after chlorination may promote formation of nitrogenous disinfectant by-products and growth of microorganisms in the distribution system. In this study, an existing bioassay to determine BDON in wastewater was adapted and optimized, and its application was tested on samples from four treatment stages of a water treatment plant including ozonation and biologically active filtration. The optimized bioassay was able to detect BDON in 50 μg L(-1) as N of glycine and glutamic solutions. BDON in raw (144-275 μg L(-1) as N), softened (59-226 μg L(-1) as N), ozonated (190-254 μg L(-1) as N), and biologically filtered (17-103 μg L(-1) as N) water samples varied over a sampling period of 2 years. The plant on average removed 30% of DON and 68% of BDON. Ozonation played a major role in increasing the amount of BDON (31%) and biologically active filtration removed 71% of BDON in ozonated water.
authors.affiliation: Department of Civil and Environmental Engineering, North Dakota State University, Dept. # 2470, P.O. Box 6050, Fargo, ND 58108-6050, USA.
authors.forename: Tanush
authors.initials: T
authors.lastname: Wadhawan
authors.affiliation: Department of Agriculture and Biosystems Engineering, North Dakota State University, Fargo, ND 58108, USA.
authors.forename: Halis
authors.initials: H
authors.lastname: Simsek
authors.affiliation: Moore Engineering, Inc., West Fargo, ND 58078, USA.
authors.forename: Murthy
authors.initials: M
authors.lastname: Kasi
authors.affiliation: City of Moorhead Drinking Water Treatment Plant, Fargo, ND 58102, USA.
authors.forename: Kristofer
authors.initials: K
authors.lastname: Knutson
authors.affiliation: Department of Veterinary and Microbiological Sciences, North Dakota State University, Fargo, ND 58108, USA.
authors.forename: Birgit
authors.initials: B
authors.lastname: Prüβ
authors.affiliation: Department of Veterinary and Microbiological Sciences, North Dakota State University, Fargo, ND 58108, USA.
authors.forename: John
authors.initials: J
authors.lastname: McEvoy
authors.affiliation: Department of Civil and Environmental Engineering, North Dakota State University, Dept. # 2470, P.O. Box 6050, Fargo, ND 58108-6050, USA. Electronic address: eakalak.khan@ndsu.edu.
authors.forename: Eakalak
authors.initials: E
authors.lastname: Khan
mesh_terms: D001419:Bacteria / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D001673:Biodegradation, Environmental / Q000187:drug effects; D002244:Carbon / Q000032:analysis; D009584:Nitrogen / Q000032:analysis*; D009930:Organic Chemicals / Q000032:analysis*; D010084:Oxidation-Reduction / Q000187:drug effects; D010126:Ozone / Q000494:pharmacology*; D012015:Reference Standards; D012995:Solubility; D018508:Water Purification
chemical_list: D009930:Organic Chemicals; D010126:Ozone; D002244:Carbon; D009584:Nitrogen
keywords: Biodegradable dissolved organic nitrogen (BDON); Dissolved organic nitrogen (DON); Drinking water; Total dissolved nitrogen (TDN)