title: Effect of soluble sulfide on the activity of luminescent bacteria.
abstract: Sulfide is an important water pollutant widely found in industrial waste water that has attracted much attention. S²⁻, as a weak acidic anion, is easy hydrolyzed to HS⁻ and H₂S in aqueous solution. In this study, biological tests were performed to establish the toxicity of sulfide solutions on luminescent bacteria. Considering the sulfide solution was contained three substances--S²⁻, HS⁻ and H₂S--the toxicity test was performed at different pH values to investigate which form of sulfide increased light emission and which reduced light emission. It was shown that the EC₅₀ values were close at pH 7.4, 8.0 and 9.0 which were higher than pH 5 and 10. The light emission and sulfide concentrations displayed an inverse exponential dose-response relationship within a certain concentration range at pH 5, 6.5 and 10. The same phenomenon occurred for the high concentration of sulfide at pH 7.4, 8 and 9, in which the concentration of sulfide was HS⁻ >> H₂S > S²⁻. An opposite hormesis-effect appeared at the low concentrations of sulfide.
authors.affiliation: Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 20092, China. 6598sy@tongji.edu.cn
authors.forename: Ying
authors.initials: Y
authors.lastname: Shao
authors.forename: Ling-Ling
authors.initials: LL
authors.lastname: Wu
authors.forename: Hong-Wen
authors.initials: HW
authors.lastname: Gao
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
mesh_terms: D001419:Bacteria / Q000187:drug effects* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D049449:Luminescence; D012995:Solubility; D012996:Solutions; D013440:Sulfides / Q000737:chemistry / Q000494:pharmacology*; D014873:Water Pollutants / Q000737:chemistry
chemical_list: D012996:Solutions; D013440:Sulfides; D014873:Water Pollutants