title: Effects of inorganic salts on denitrifying granular sludge: The acute toxicity and working mechanisms.
abstract: It is highly significant to investigate the toxicity of inorganic salts to denitrifying granular sludge (DGS) and its mechanism since the application of high-rate denitrification is seriously limited in the treatment of saline nitrogen-rich wastewaters. The batch experiments showed that the IC50 (half inhibition concentration) and LC50 (half lethal concentration) of NaCl, Na2SO4 and Na3PO4 on DGS were 11.46, 21.72, 7.46 g/L and 77.35, 100.58, 67.92 g/L respectively. Based on the analysis of specific denitrifying activity, the live cell percentage, the cell structure, and the DNA leakage, the toxicity of low salinity was ascribed to the inhibition of denitrifying activity and the toxicity of high salinity was ascribed to both the inhibition of denitrifying activity and the lethality of denitrifying cell.
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China.
authors.forename: Ru
authors.initials: R
authors.lastname: Wang
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China. Electronic address: pzheng@zju.edu.cn.
authors.forename: Ping
authors.initials: P
authors.lastname: Zheng
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China.
authors.forename: A-Qiang
authors.initials: AQ
authors.lastname: Ding
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China.
authors.forename: Meng
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China.
authors.forename: Abbas
authors.initials: A
authors.lastname: Ghulam
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Yang
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China.
authors.forename: He-Ping
authors.initials: HP
authors.lastname: Zhao
mesh_terms: D019149:Bioreactors; D058440:Denitrification; D009584:Nitrogen; D012492:Salts / Q000737:chemistry*; D012722:Sewage / Q000737:chemistry*; D012965:Sodium Chloride; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry
chemical_list: D009584:Nitrogen; D012492:Salts; D012722:Sewage; D012965:Sodium Chloride; D062065:Wastewater
keywords: Activity inhibition; Acute toxicity; Cell lethality; Denitrifying granular sludge; Inorganic salts