Environment cadmium speciation

Hirsh D., Banin A. Cadmium speciation in soil solutions. J Environ Qual 1990 19 366-372. 

Hirsch, D., and Banin, A. J. (1990). Cadmium speciation in soil solutions the residual effect of sewage sludge on heavy metal content of tobacco and peanut. J. Environ. Qual. 19, 366-372. 

Abstract This chapter reports an analysis of literature dedicated to the speciation of cadmium in various environmental compartments, i.e., atmosphere, natural waters, soils and sediments. The difficulty of the cadmium speciation studies, due to the variability of composition of different natural systems and to the low cadmium concentration in the environment, is highlighted. As an alternative approach, cadmium behavior is assessed by modelling its reactivity towards the main classes of ligands usually present in natural systems. The stability of cadmium complexes with... 

As already discussed in previous chapters, speciation plays an important role in cadmium toxicity and exposure to living organisms, influences its availability, accumulation, bio-modification, as well as its transport inside the organisms, and within and between environmental compartments too. That is why speciation studies are of fundamental importance to fully appreciate how this element behaves in the environment. Unfortunately, a careful analysis of literature dedicated to the speciation of cadmium reveals that this term is often abused and erroneously used, resulting in a consistent reduction of the papers really matching lUPAC recommendations and being effectively dedicated to cadmium speciation. 

Fig. 15-11 Effects of strong complexation on metal ion toxicity, (a) Increasing concentration of NTA, a strong multi-dentate complexing agent, decreases the toxicity of Cd to grass shrimp. All systems have equal concentrations of total Cd. (b) When the results are replotted showing survival as a function of Cd concentration, the data for all concentrations of NTA collapse to a single curve. (Reprinted with permission from W. G. Sunda et al. (1978). Effect of chemical speciation on toxicity of cadmium to grass shrimp, Palaemonetes pugio importance of free cadmium ions. Environ. Sci. Technol. 12,409-413, American Chemical Society.)...

Sandrin, T. and Maier, R., Effect of pH on cadmium toxicity, speciation, and accumulation during naphthalene biodegradation, Environ Toxicol Chem, 21 (10), 2075-2079, 2002. 

Kim, N.D. and Fergusson, J.E., Effectiveness of a commonly used sequential extraction techniques in determining the speciation of cadmium in soils. Sci Total Environ 1991 105 191-209. 

Cadmium is a silver-white, blue-tinged, lustrous metal that melts at 321°C and boils at 767°C. This divalent element has an atomic weight of 112.4, an atomic number of 48, and a density of 8.642 g/cm3. It is insoluble in water, although its chloride and sulfate salts are freely soluble (Windholz et al. 1976 USPHS 1993). The availability of cadmium to living organisms from their immediate physical and chemical environs depends on numerous factors, including adsorption and desorption rates of cadmium from terrigenous materials, pH, Eh, chemical speciation, and many... 

Luten, J.B., W. Bouquet, M.M. Burggraaf, and J. Rus. 1986. Accumulation, elimination, and speciation of cadmium and zinc in mussels, Mytilus edulis, in the natural environment. Bull. Environ. Contam. Toxicol. 37 579-586. 

Sunda, W.G., Engel, D.W. and Thuotte, R.M., 1978. Effects of chemical speciation on toxicity to grass shrimp, Paleometes pugio importance of free cadmium ion. Environ. Sci. Technol., 12 409-413. 

Berggren, D. (1989) Speciation of aluminium, cadmium, copper, and lead in humic soil solutions - a comparison of the ion exchange column procedure and equilibrium dialysis. Int.J. Environ. Anal. Chem., 35, 1-15. 

Berggren, D. (1990) Speciation of cadmium(II) using Donnan dialysis and differential-pulse anodic stripping voltammetry in a flow-injection system. Int. J. Environ. Anal. Chem., 41, 133-148. 

Chakrabarti, C.L., Lu, Y., Gregoire, D.C., Back, M.H. and Schroeder, W.H. (1994) Kinetic studies of metal speciation using Che lex cation exchange resin application to cadmium, copper, and lead speciation in river water and snow. Environ. Sci. Technol, 28, 1957-1967. 

Lamy, L, Gambier, P., and Bourgeois, B. (1994). Lead and cadmium complexation with soluble organic carbon and speciation in alkaline soil leachates. Environ. Geochem. Health 16, 1-16. 

Raspoe B (1980) Distribution and speciation of cadmium in natural waters. In Nriagu JO, ed. Cadmium in the environment. Part I, Chapter 6, pp.147-236. John Wiley Sons, New York. 

Sauve, S., Norvell, W.A., McBride, M.B., Hendershot, W, 2000. Speciation and complexation of cadmium in extracted soil solutions. Environ. Sci. Technol. 34, 291-296. 

In the following sections, the original speciation of metals released during various industrial activities are reviewed, and possible changes in speciation in the environment outlined. The spatial location of metallic compounds at specific types of site is not discussed in detail the reader is referred to the Department of the Environment s Industry Profiles (Department of the Environment 995a-o). The present review is focused on cadmium, arsenic, chromium, mercury, lead, copper, nickel and zinc because they are conunon at industrially contaminated sites in forms which are considered hazardous. Cadmium, arsenic, chromium, mercury and lead were identified as groundwater contaminants representing threats to human health in a comprehensive US survey (Knox Canter 1996). 

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