Cadmium ion toxicity

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.)...

The development of chelating agents for use in metal ion removal is still in its infancy and suitable antidotes are not yet available for treating poisoning by beryllium, cadmium, manganese, thallium and many other toxic metal ions. Radiostrontium and radium pose particular problems because of their chemical similarities to calcium. 

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. 

Endogenous substances other than metallothionein may be involved in minimizing the effects of heavy metals and excreting them from the body. Hepatic (liver) glutathione, discussed as a phase II conjugating agent in Section 7.4, plays a role in the excretion of several metals in bile. These include the essential metals copper and zinc toxic cadmium, mercury(II), and lead(II) ions and organometallic methyl mercury. 

Early life forms thriving near thermal vents in waters enriched in heavy metal ions would have had to have been endowed with mechanisms to deal with toxic metal ions and it is conceivable that efflux mechanisms for these metals evolved before or concomitandy with their use as cofactors. In line with such a hypothesis, the CPx-type ATPases encompass a wider spectrum of ion specificities than the non-heavy metal ATPases, now including Cu+, Ag+, Zn +, Cd +, and Pb. It is to be expected that other metal ions will be added to this list. ATPases transporting silver, zinc, cadmium, and lead are involved in bacterial resistance to these toxic metal ions, while copper-transporting ATPases have a role both in copper uptake to meet cellular demands and in copper extrusion when ambient... 

Cadmium is a divalent metal ion. It is a toxic metal ion that can induce damage to the reproductive system. In general, cadmium can bind to sites of proteins that are normally used to bind zinc, (t is possible that the cadmium-induced damage to the reproductive system results from the binding to the zinc fingers of the steroid hormone-binding proteins. 

Srivastava S.K., R, Tyagi, N. Pant, and N. Pal. 1989. Studies on the removal of some toxic metal ions. Part II. Removal of lead and cadmium by montmorillonite and kaolinite. Environ. Technol, Lett. 10 275-282. 

Acid rain is a threat to our environment because it can increase the concentration of toxic metal ions, such as Cd and Cr, in rivers and streams. If cadmium and chromium are present in sediment as Cd(OH)2 and Cr(OH)3, write reactions that demonstrate the effect of acid rain. Use the library to find the properties of cadmium and chromium responsible for their environmental impact. 

Stohs, S. J. et al., Oxidative mechanisms in the toxicity of chromium and cadmium ions, J. Environ. Pathol Toxicol Oncol, 20, 77, 2001. 

The removal of solvated cadmium ions (Cd ) from water has been studied because ionic cadmium is a toxic element (itai-itm disease in Japan) and one of the main metallic pollutants of industrial aqueous effluents (electrodeposition, Ni-Cd batteries etc.). When alumina-deposited nickel, previously reduced under a hydrogen flow, is suspended in a Cd solution, a quick and strong decrease in pH is observed, followed by a slow pH increase with time. The pH decrease has been interpreted by the reaction ... 

As a result of rapid industrialization, the disposal of heavy metals into the environment has increased. Many industries discharge aqueous effluents that contain heavy metals, such as copper, cadmium, zinc and mercury (Saygideger et al. 2005). These metal ions can be harmful to aquatic life, and water contaminated by toxic metal ions remains a serious public health problem for human health (Pehlivan et al. 2008). Therefore, it is of great practical interest to explore ways to effectively remove these heavy metal ions from the wastewaters before their discharge, and to possibly separate them for recovery and re-use. 

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