Effective cadmium compounds

Oberdorster G. 1992. Pulmonary deposition, clearance and effects of inhaled soluble and insoluble cadmium compounds. In Nordberg GF, Herber RFM, Alessio L, eds. Cadmium in the human environment Toxicity and carcinogenicity. Lyon International Agency for Research on Cancer,... 

In a review of the course and mechanism of the catalytic decomposition of ammonium perchlorate, the considerable effects of metal oxides in reducing the explosion temperature of the salt are described [1], Solymosi s previous work had shown reductions from 440° to about 270° by dichromium trioxide, to 260° by 10 mol% of cadmium oxide and to 200°C by 0.2% of zinc oxide. The effect of various concentrations of copper chromite , copper oxide, iron oxide and potassium permanganate on the catalysed combustion of the propellant salt was studied [2], Similar studies on the effects of compounds of 11 metals and potassium dichromate in particular, have been reported [3], Presence of calcium carbonate or calcium oxide has a stabilising effect on the salt, either alone or in admixture with polystyrene [4],... 

Production. Since soluble cadmium compounds have a toxic effect on human beings and the environment, all wastewater originating from the production of cadmium pigments must be treated to remove cadmium. In the EU, the following... 

In the United States, the National Toxicology Program (NTP) has shown that cadmium and different cadmium compounds (including cadmium sulfide) have a carcinogenic effect in animal experiments. 

U. Heinrich et al. Investigation of the Carcinogenic Effects of Various Cadmium Compounds after Inhalation Exposure in Hamsters and Mice, Exp. Pathol. 38, in press. 

Complexing of zinc and cadmium by amino acids, both natural and otherwise, and of polypeptides, has been the subject of study for many years because of the importance of zinc-protein systems and the physiological effect of cadmium compounds (see Section 56.1.14). 

Some cadmium compounds, including simple salts, were revealed to be excellent catalysts for the enantiosymmetric polymerisation of propylene sulphide [156,157], For instance, the proportion of isotactic diads in the polypropylene sulphide) sample obtained in polymerisation with the cadmium (7 )-tartrate catalyst was more than 95%, higher than the 69% which was characteristic of a polymer sample prepared using the zinc (i )-tartrate catalyst [158]. The superior stereoselectivity of the cadmium (i )-tartrate catalyst is also borne out by the more effective separation into fractions having opposite optical rotations of the polypropylene sulphide) yielded by cadmium tartrate, compared with that yielded by zinc (i )-tartrate. Note the quite different behaviour of these two catalysts in terms of their stereoelectivity in the polymerisation of propylene sulphide only very slight optical activity was found for the polypropylene sulphide) sample prepared using cadmium tartrate, whereas that associated with the polymer sample obtained with zinc tartrate was found to have a much higher value [158]. 

Milled rigid sheets of poly (vinyl chloride) on heating at 185°C. lose weight at a rate which increases with time. By polymer fractionation procedures, it was shown the rate of hydrogen chloride loss increases as the content of tetrahydro-furan-insoluble resin increases. The insoluble resin content accumulates at a rate which depends, in part, on the additive present. This insolubilization reaction is catalyzed by cadmium compounds. The increased dehydrochlorination rate of the insoluble crosslinked resins may result from the susceptibility of the crosslinked structures to oxidation and from the subsequent thermal degradation of the oxidation products. The effects of various common additives on the rates of insolubilization and weight loss are described. 

An experimental teratogen. Other experimental reproductive effects. Human mutation data reported. When heated to decomposition it emits toxic fumes of Cd. See also CADMIUM COMPOUNDS. 

NIOSH PEL (Cadmium, dust and fume) Reduce to lowest feasible level SAFETY PROFILE Confirmed human carcinogen. Moderately toxic to humans by inhalation. Human pulmonary system effects by inhalation, including coughing, difficult breathing, and cyanosis. A strong irritant via inhalation. When heated to decomposition it emits toxic fumes of Cd. See also CADMIUM OXIDE and CADMIUM COMPOUNDS. 

The effects of extensive cadmium exposure are not known, but are thought to include heart and kidney disease, high blood pressure, and cancer. A cadmium poisoning disease called itai-itai, Japanese for ouch-ouch, causes aches and pains in the bones and joints. In the 1970s, a number of cases of itai-itai were reported in Japan when waste from a zinc refinery got into the public water supply. Those wastes contained cadmium compounds. 

The earlierst reports of the carcinogenic effect of cadmium on man are from 1965 [91]. In workers exposed to the dust, carcinomas of the prostate and malignant processes in the gastrointestinal tract, kidneys, liver and lung were observed [92, 93]. Teratogenic effects are also reported for certain cadmium compounds (cadmium chloride, cadmium sulphate) [94]. 

Poisons can be acute (with immediate effect, e.g., hydrogen cyanide (HCN)) or chronic (referring to the systemic damage done after repeated exposure to low concentrations over long periods of time, e.g., heavy metals like mercury, lead, cadmium and also vinyl chloride). The chemicals most often associated with chronic toxicity are also carcinogens (e.g., benzene, cadmium compounds), which are problematic because when, if at all, the... 

The chemical basis of this time period may not be uniform for all of the type b metals. For mercury(II) it appears to be related to the occurrence of a minimum amount of what is literally the destruction of tissue and proteins. In the case of cadmium it appears to have a different basis at least in part. Subsequent to the injection of an otherwise lethal dose of a cadmium compound there is a relatively short period when it can be complexed and removed and the animal saved. As the interval between the cadmium injection and that of the antidote (e.g. CaEDTA or CaDTPA) increases, the cadmium becomes more and more difficult to mobilize and a point is soon reached where the antidote is without effect ( 5). In the same fashion, aged cadmium deposits are apparently resistant to mobilization by EDTA ). 

Table 4.1-162 Effective masses of electrons (in units of the electron mass mo) for cadmium compounds...

The most significant of the heat stabilizers are lead compounds, which accounted for nearly 68% of volume in 1989, but by 1994 had declined to 64%. Barium/cadmium compounds are the next most important, followed by organotin compounds (which actually come second in value terms). Barium/ zinc and calcium/zinc compounds have a high growth rate due to substitution in some cases of barium/zinc for barium/cadmium because of fears for the effects of cadmium on the environment and health, after it had been found that soluble cadmium products could have an adverse effect on the environment when used at above certain critical levels. 

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