Cadmium organ toxicity

Regarding the toxicity of some metal ions, it is well known that mercury, lead and cadmium are toxic to organisms, and early detection in the environment is... 

At emulsion crumb rubber facilities, a well-operated biological treatment facility permits compliance with BPT limitations and reduces organic toxic pollutant levels. Toxic metals that may not be reduced include chromium, cadmium, copper, selenium, and mercury. Tables 16 and 17 show pollutant removal efficiencies at two emulsion cmmb plants. 

Thus, cadmium causes multi-organ toxicity, and at least some of the toxic effects are due to it being a divalent metal similar to zinc and able to bind to sulfydryl groups. 

Cadmium is a relatively rare metal and its abundance in the earth s crust is estimated at less than 1 mg kg Cadmium is closely related to zinc in its chemical properties and in nature is always found associated with zinc. It is a divalent metal, readily forming halides of which chloride is the most reactive. It is soluble in most inorganic and some organic acids, but insoluble in alkalies. In the presence of sulfide, cadmium precipitates out of solution as cadmium sulfide (Figure 12.16). Cadmium is toxic to living organisms in virtually all of its chemical forms. The environmental presence of cadmium is... 

Research on cadmium pollution has received increasing international attention inasmuch as cadmium is toxic and can cause severe human health problems such as kidney disorder and itai-itai disease (Webb, 1979 Alloways, 1995). The influence of residence time and organic acids on Cd desorption from pure goethite has been studied (Glover et al., 2002). However, pure iron oxides rarefy... 

Cadmium is absorbed more efficiently by the lungs (30 to 60%) than by the gastrointestinal tract. For inhalation exposure, both the lungs and kidneys are target organs for cadmium-induced toxicity. Inhalation exposure to cadmium and cadmium compounds may result in effects including headache, chest pains, muscular weakness, pulmonary edema, and death. Renal toxicity (tubular proteinosis) may also result from inhalation exposure to cadmium. 

Metals that are soft Lewis acids, for example cadmium, mercury, and lead, are extremely hazardous to living organisms. Tin, in contrast, is not. One reason is that tin oxide is highly insoluble, so tin seldom is found at measurable levels in aqueous solution. Perhaps more important, the toxic metals generally act by binding to sulfur in essential enz Tnes. Tin is a harder Lewis acid than the other heavy metals, so it has a lower affinity for sulfur, a relatively soft Lewis base. 

Other studies use soil or sediment samples for a more accurate indication of microbial activity in natural environments. In these samples, organic matter and clay particles play a role in metal toxicity.76112113 Both organic material and clay particles in soil can bind metals and reduce their bioavailability. For example, Pardue et al.87 demonstrated that much less solution-phase cadmium was required to inhibit trichloroaniline (TCA) dechlorination in a mineral-based soil than in a soil containing a higher concentration of organic matter. Other studies have shown that adding clay minerals to a medium mitigates toxicity. Clay minerals, such as kaolinite, montmorillonite, bentonite, and vermiculite, can bind to metals to decrease the amount that is bioavailable.112 115... 

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