Compounds of Arsenic

Arsenic Peroxides. Arsenic peroxides have not been isolated however, elemental arsenic, and a great variety of arsenic compounds, have been found to be effective catalysts ia the epoxidation of olefins by aqueous hydrogen peroxide. Transient peroxoarsenic compounds are beheved to be iavolved ia these systems. Compounds that act as effective epoxidation catalysts iaclude arsenic trioxide, arsenic pentoxide, arsenious acid, arsenic acid, arsenic trichloride, arsenic oxychloride, triphenyl arsiae, phenylarsonic acid, and the arsenates of sodium, ammonium, and bismuth (56). To avoid having to dispose of the toxic residues of these reactions, the arsenic can be immobi1i2ed on a polystyrene resia (57). 

The commercial uses of arsenic compounds in 1988, measured in terms of elemental arsenic, are wood (qv) preservatives, 69% agricultural products (herbicides (qv) and desiccants (qv)), 23% glass (qv), 4% nonferrous alloys and electronics, 2% and animal feed additives and pharmaceuticals (qv), 2% (see Feeds AND feed additives). Chromated copper arsenate (CCA) [11125-95-4] is the most widely used arsenic-based wood preservative. The Environmental Protection Agency has, however, restricted the use of arsenical wood preservatives to certified appHcators. 

Arsenic compounds must be considered extremely poisonous. Dust or fumes irritate mucous membranes and lead to arsenical poisoning. When swallowed they irritate the stomach and affect the heart, Hver, and kidneys. Nervousness, thirst, vomiting, diarrhea, cyanosis, and coUapse are among the symptoms of arsenical poisoning (3). In spite of the toxicity of arsenic compounds, there is evidence that arsenic is an essential nutrient for several animal species (4). 

Caution Because tellurium compounds have toxic effects similar to those of arsenic compounds care should be taken not to bring tellurium tetrachloride and its reaction products into contact with the skin. Avoid breathing fumes and dust of tellurium compounds. In addition, hydrogen chloride is evolved in Step A, and pyrophoric Raney nickel is used in Step B. Therefore all manipulations described in this procedure must be carried out in an efficient fume hood. 

The physiological properties of selenium compounds are similar to those of arsenic compounds. Any selenium dioxide solid or solution spilled on the skin should be removed immediately by washing under running water. 

Dechnicke K, Shihada A-F (1976) Structural and Bonding Aspects in Phosphorus Chemistry-Inorganic Derivates of Oxohalogeno Phosphoric Acids. 28 51-82 Denning RG (1992) Electronic Structure and Bonding in Actinyl Ions. 79 215-276 Dhubhghaill OMN, Sadler PJ (1991) The Structure and Reactivity of Arsenic Compounds. 

The mobility of arsenic compounds in soils is affected by sorp-tion/desorption on/from soil components or co-precipitation with metal ions. The importance of oxides (mainly Fe-oxides) in controlling the mobility and concentration of arsenic in natural environments has been studied for a long time (Livesey and Huang 1981 Frankenberger 2002 and references there in Smedley and Kinniburgh 2002). Because the elements which correlate best with arsenic in soils and sediments are iron, aluminum and manganese, the use of Fe salts (as well as Al and Mn salts) is a common practice in water treatment for the removal of arsenic. The coprecipitation of arsenic with ferric or aluminum hydroxide has been a practical and effective technique to remove this toxic element from polluted waters... 

Arsenic is a major constituent of at least 245 mineral species, of which arsenopyrite is the most common (NAS 1977). In general, background concentrations of arsenic are 0.2 to 15 mg/kg in the lithosphere, 0.005 to 0.1 pg/m3 in air, <10 pg/L in water, and <15 mg/kg in soil (NRCC 1978 ATSDR 1992). The commercial use and production of arsenic compounds have raised local concentrations in the environment far above the natural background concentrations (Table 28.1). 

Cancer incidence and other abnormalities in natural resources from areas with elevated arsenic levels, and the relation to potential carcinogenicity of arsenic compounds... 

Aposhian, H.V., R. Zakharyan, Y. Wu, S. Healy, and M.M. Aposhian. 1997. Enzymatic methylation of arsenic compounds. II. An overview. Pages 296-321 in C.O. Abernathy, R.L. Calderon, and W.R. Chappel (eds.). Arsenic. Exposure and Health Effects. Chapman Hall, London. 

Irgolic, K.J., E.A. Woolson, R.A. Stockton, R.D. Newman, N.R. Bottino, R.A. Zingaro, P.C. Kearney, R.A. Pyles, S. Maeda, W.J. McShane, and E.R. Cox. 1977. Characterization of arsenic compounds formed by Daphnia magna and Tetraselmis chuii from inorganic arsenate. Environ. Health Perspec. 19 61-66. 

Kaise, T. and S. Fukui. 1992. The chemical form and acute toxicity of arsenic compounds in marine organisms. Appl. Organometall. Chem. 6 155-160. 

Spehar, R.L., J.T. Fiandt, R.L. Anderson, and D.L. DeFoe. 1980. Comparative toxicity of arsenic compounds and their accumulation in invertebrates and fish. Arch. Environ. Contam. Toxicol. 9 53-63. 

Yoshida, T., Shimamura, T., and Shigeta, S., Immunological Effects of Arsenic Compounds on Mouse Spleen Cells In Vitro, Tokai J. Exp. Clin. Med, 11, 353, 1986. 

The introduction of the arsinic acid group into the aromatic nucleus is of great interest in connexion with the therapeutic application of arsenic compounds in combating certain infectious diseases (atoxyl = sodium arsanilate salvorsan). 

Cullen, W.R. Eigendorf, G.K. Peigantis, S.A. DCI-MS of Arsenic Compounds Present in the Marine and Terrestrial Environment. Rapid Commun. Mass Spectrom. 1993, 7,33-36. 

Chouchane, S. Snow, E. T. in Vitro Effect of Arsenical Compounds on Glutathione-Related Enzymes. Chem. Res. Toxicol. 2001, 14, 517-522. 

Arsenic trioxide is used as a starting material to prepare metallic arsenic and a number of arsenic compounds. It is also used as a decolorizer for bottle glass in pigments and ceramic enamels for preserving hides as a wood preservative as an analytical standard in oxidimetry titrations and in many rodenticide and herbicide formulations. 

Arsine is used as a reducing agent and to synthesize many organoarsine derivatives. It is also used as a doping agent for solid state electronic components. Earlier, it was used as a military poison gas. It does not occur freely in nature but is susceptible to form upon contact of arsenic compounds with acid in presence of a metal. Thus commercial acids stored in metal tanks and contaminated with arsenic impurities may produce arsine. 

DubhghaUI. O. M. Ni, Sadler, P. J. The Structure and Reactivity of Arsenic Compounds. Biological Activity and Drug Design. Vol. 78, pp. 129-190. 

B.6 Speciation of Arsenic Compounds by Ion-Exchange High-Performance Liquid Chromatography with Hydride Generation Atomic Fluorescence Detection. 

Recently, Sakai et al. have combined flame Zeeman atomic absorption spectrometry (FZAAS) with selective vapourisation of the spaaes from a sample, placed in a crucible which is slowly heated, to investigate the speciation of arsenic compounds in oyster tissue. This method could prove useful if the top temperature reached by the system is high enough to allow the vapourisation of a wider variety of species that may exist in biological samples. Presently, the highest temperature attainable is 400 °C. 

No m loration of this series has yet been made. The members of it will doubtless be found to present dose analogies with e corresponding series of arsenic compounds. 

The use of arsenic and its organic derivatives as herbicides, pesticides, and wood preservatives has been increasing steadily each year. Large quantities of arsenical compounds are manufactured by the chemical industry and eventually find their way into the environment (l ). About seventy percent of these chemicals are inorganic in form and the rest are organoarsenicals (2). Of the organoarsenicals, the most important species from the point of view of use and health effects are monomethylarsonic acid (MMA), dimethylarsenic acid (DMA), and p-aminophenylarsonic acid (p-APA). 

Occurrence and Distribution of Arsenic Compounds in Marine Samples... 

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