|
(26-07) Measuring the Bioavailable/Toxic Concentration of Copper in Reconstituted Water by Using Anodic Tripping Voltammetry and Vibrio-qinghaiensis sp.Nov.-Q67 Bioassay. Wang, Zijian*,1, Huang, Shengbiao2, 1 State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Beijing, China2 ABSTRACT- The speciation of a metal, rather than its total concentration, is the key to understanding its effect on the biota. Morel formulated the free-ion-activity model (FIAM) to imply that a constant degree of biological effect will occur at a constant chemical activity of the free ion of metal. These studies have lead to the conviction that the concentration of free ionic metal is the key determinant of toxicity. This appears to be not supportable in some other studies. Labile concentration of Cu measured by differential pulse anodic stripping voltammetry with double acidification method (DAM-DPASV) gived a good approximation of electroactive metal fraction, which led to the deposition procedure of labile concentration of a metal on the surface of electrode approximating to the kinetics of its uptake processes by cells of organisms as closely as possible. This papers studied relationship between labile concentration and toxicity of Cu by using Vibrio-qinghaiensis sp.Nov.-Q67 bioassays and (DAM-DPASV), under joint function of multi-ligands (NaHCO3, Cl-, EDTA and FA) and spiked natural waters. The results showed that [Cu*] or a defined bioavailable concentration of Cu, could be a suitable parameter for the biological response to Cu in synthetic media. Key words: Copper, speciation, toxicity, model |
