Selenium with Silver

The metabolic interactions of selenium with silver and their influence 

As shown in Table V, silver significantly depressed plasma copper levels and ceruloplasmin activity but had no influence on plasma zinc levels. As expected, silver accumulated in the plasma. The depressing effect of silver on ceruloplasmin activity is in agreement with earlier work (Whanger and Weswig, 1970). These workers found silver to have the most depressing effect on plasma ceruloplasmin activity, followed by cadmium, molybdenum, zinc, and sulfate in descending order. 

Silver accumulated in the liver with each increase of dietary silver, and this significantly increased hepatic copper and iron content (Table VI). However, silver had no influence on the zinc content of the liver. Dietary selenium significantly increased the silver content of the liver, consistent with the results of Wagner et al. (1975). The metabolic interaction of silver with copper in the rat is in agreement with findings by others using the chick (Hill et al, 1964 Peterson and Jensen, 1975b). 

Diet Ag effect significant (P 0.01). Diet Ag effect significant (P 0.01). 

Slightly different effects of silver on the renal mineral content were observed (Table VII). In contrast to the liver, silver had no significant effect on renal copper and iron levels. As for the liver, silver had no effect on renal zinc levels. Also consistent with the liver, silver accumulated in the kidneys, and selenium caused a significant increase in this accumulation. However, in contrast to the liver, there was a significant interaction between selenium and silver with respect to the accumulation of silver in this organ. This indicates that only a combination of selenium and silver brings about this effect. 

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Present data indicate that silver has no effect on zinc in any rat tissue. This finding is in agreement with work with the chick (Hill and Matrone, 1970). Since the Ag ion is like the cupric ion and unlike the cuprous and zinc ions, it is proposed that divalent silver is the metabolic active form. Furthermore, the data of Tables V-VII indicate that the effect of silver on copper and iron metabolism, and the interaction of selenium with silver, are tissue dependent. Hence, there appears to be a metabolic interaction between selenium and silver in some tissues, and this interaction influences copper and iron levels. 

Pesticide wastes that are hazardous by reason of the characteristics are those which are either solvent based and have a flash point <60 °C are aqueous and have a pH <2.0 or >12.5 release HCN or H2S upon contact with acids or leach greater than threshold levels of one or more of the elements arsenic, barium, cadmium, chromium, lead, mercury, selenium and silver, or the pesticides endrin, lindane, methoxychlor, toxa-phene, 2,4-D or 2,4,5-TP. To date, these are the only pesticides for which thresholds have been established. 

The next five chapters deal with deposition of specific groups of semiconductors. In Chapter 4, II-VI Semiconductors, all the sulphides, selenides, and (what little there is on) tellurides of cadmium (most of the chapter), zinc (a substantial part), and mercury (a small part). (Oxides are left to a later chapter.) This chapter is, understandably, a large one, due mainly to the large amount of work carried out on CdS and to a lesser extent on CdSe. Chapter 5, PbS and PbSe, provides a separate forum for PbS and PbSe, which provided much of the focus for CD in earlier years. The remaining sulphides and selenides are covered in Chapter 6, Other Sulphides and Selenides. There are many of these compounds, thus, this is a correspondingly large chapter. Chapter 7, Oxides and Other Semiconductors, is devoted mainly to oxides and some hydroxides, as well as to miscellaneous semiconductors that have only been scantily studied (elemental selenium and silver halides). These previous chapters have been limited to binary semiconductors, made up of two elements (with the exception of elemental Se). Chapter 8, Ternary Semiconductors, extends this list to semiconductors composed of three elements, whether two different metals (most of the studies) or two different chalcogens. 

The three samples with the optimum reagent ratios (Ratio A, B, and C) were subjected to TCLP analysis and the leachate was analyzed for arsenic, barium, cadmium, chromium, cobalt, lead, mercury, nickel, selenium and silver. 

In the absence of the halogens the selenium may be oxidised to selenious acid by heating with nitric acid in a Carius tube at 240° to 300° C. The resulting liquid is nearly neutralised, excess of zinc oxide added, and the mixture titrated with silver nitrate using chromate as external indicator 3... 

A wide range of ligands of the type RXCH2C02H where R = alkyl, alkenyl or aryl and X = S, Se or Te have been reacted with silver ions and thermodynamic data for some representative examples are given in Table 49.358,359 The silver-selenium complexes were found to be more stable than their silver-sulfur analogues as a result of both larger favourable enthalpy and smaller unfavourable entropy changes. 

Cabe PA, Carmichael NG, Tilson FIA. 1979. Effects of selenium, alone and in combination with silver or arsenic, in rats. Neurobeh Toxicol 1 275-278. 

Ganther HE. 1980. Interactions of vitamin E and selenium with mercury and silver. Ann NY Acad Sci 355 212-226. 

Whanger PD. 1985. Metabolic interactions of selenium with cadmium, mercury, and silver. Adv Nutr Res 7 221-250. 

The 1-phenyl 3-carboxaldehyde, was found to resist oxidation with silver oxide or selenium dioxide, but was destroyed with permanganate. °9 H as recently converted to l-phenyl-4-methyl-7-azaindole-3-acetic acid and l-phenyl-4-methyl-7-azatryptophan via its azlactone derivative. 9 ... 

Germanium minerals are extremely rare but the element is widely distribnted in trace amounts. Its abundance ratio is about 7 x 10 % and it is mainly associated with copper, zinc, lead, selenium, arsenic, silver, iron, and so on. There are twenty-one isotopes Ge, Ge, Ge, Ge, Ge are naturally occurring. Germaiuum is common in organisms, but it is not an indispensable trace element. In humans, it is nontoxic, but when it reaches 1000 ppm in animal s food, the growth of animals wifi be inhibited and 50% of them will die. 

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