Toxicity, of arsenic

The toxicity of arsenic ranges from very low to extremely high depending on the chemical state. Metallic arsenic and arsenious sulfide [1303-33-9] AS2S2, have low toxicity. Arsine is extremely toxic. The toxicity of other organic and inorganic arsenic compounds varies (28). 

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). 

A mixture of dihydroxyacetone and inorganic arsenate can replace DHAP due to the transient formation of a monoarsenate ester which is recognized by the aldolase as a DHAP mimic21. This approach suffers from the high toxicity of arsenate, especially at the relatively high levels (>0.5 M) needed for efficient conversion, and from problems in product isolation. 

Marine algae transform arsenate into nonvolatile methylated arsenic compounds such as methanearsonic and dimethylarsinic acids (Tamaki and Frankenberger 1992). Freshwater algae and macrophytes, like marine algae, synthesize lipid-soluble arsenic compounds and do not produce volatile methylarsines. Terrestrial plants preferentially accumulate arsenate over arsenite by a factor of about 4. Phosphate inhibits arsenate uptake by plants, but not the reverse. The mode of toxicity of arsenate in plants is to partially block protein synthesis and interfere with protein phosphorylation — a process that is prevented by phosphate (Tamaki and Frankenberger 1992). 

The toxicity of arsenicals conforms to the following order, from greatest to least toxicity arsines > inorganic arsenites > organic trivalent compounds (arsenoxides) > inorganic arsenates > organic pentavalent compounds > arsonium compounds > elemental arsenic. 

Bryant, V., D.M. Newbery, D.S. McLusky, and R. Campbell. 1985. Effect of temperature and salinity on the toxicity of arsenic to three estuarine invertebrates (Corophium volutator, Macoma balthica, Tubifex costatus). Mar. Ecol. Prog. Ser. 24 129-137. 

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

Lima, A.R., C. Curtis, D.E. Hammermeister, T.P. Markee, C.E. Northcott, and L.T. Brooke. 1984. Acute and chronic toxicities of arsenic (III) to fathead minnows, flagflsh, daphnids, and an amphipod. Arch. Environ. Contam. Toxicol. 13 595-601. 

McGeachy, S.M. and D.G. Dixon. 1990. Effect of temperature on the chronic toxicity of arsenate to rainbow trout (Oncorhynchus rnykiss). Canad. Jour. Fish. Aquat. Sci. 47 2228-2234. 

Passino, D.R.M. and AJ. Novak. 1984. Toxicity of arsenate and DDT to the cladoceran Bosmina longirostris. Bull. Environ. Contam. Toxicol. 33 325-329. 

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. 

Done, A.K. and Peart, A.J. (1971). Acute toxicities of arsenical herbicides, Clin. Toxicol., 4, 343-355. 

The degree of toxicity of arsenic is dependent on the form, either inorganic or organic, and the oxidation state of the arsenical. Inorganic arsenicals are generally more toxic than organic, and the trivalent forms are more toxic than the pentavalent. 

Earlier in this century the toxicity of arsenic was utilized in medicine and, later, in warfare. In 1909 Ehrlich developed salvarsan, the first effective antisyphilis agent and one of the first... 

Magnesium arsenate has lost its industrial importance because of the toxicity of arsenic. 

Arsenate, As043, is chemically similar to phosphate in size and geometry and in its ability to enter into biochemical reactions. However, arsenate esters are far less stable than phosphate esters. If formed in the active site of an enzyme, they are quickly hydrolyzed upon dissociation from the enzyme. This fact accounts for some of the toxicity of arsenic compounds.1... 

Drobna, Z., Waters, S.B., Devesa, V. et al. (2005) Metabolism and toxicity of arsenic in human urothelial cells expressing rat arsenic (+3 oxidation state)-methyltransferase. Toxicology and Applied Pharmacology, 207(2), 147-59. 

Mkandawire, M., Lyubun, Y.V., Kosterin, P.V. and Dudel, E.G. (2004) Toxicity of arsenic species to Lemna gibba L. and the influence of phosphate on arsenic bioavailability, Environmental Toxicology 19 (1), 26-34. 

K.S. Squibb, and B.A. Fowler, The toxicity of arsenic and its compounds, in Fowler, B.A., ed., Biological and Environmental Effects of Arsenic, Amsterdam Elsevier Science, 233, 1983. 

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