Tolerance to arsenic

Mineral Feed. Mineral feed supplements for domestic animals and fowl usually contain a pure form of pulverized limestone. In fact, some state laws require the supplement to be at least 35% available calcium. Other sources of calcium are bone meal and dicalcium phosphate. Use as mineral feed has been a steadily growing market for limestone. The material is ground to 90% minus 0.15 mm (100 mesh) or 80% minus 0.9074 mm (200 mesh), is low in silica, and has strict tolerances on arsenic and fluorine (see Feeds and feed additives). 

May, T.W. and G.L. McKinney. 1981. Cadmium, lead, mercury, arsenic, and selenium concentrations in freshwater fish, 1976-77 — National Pesticide Monitoring Program. Pestic. Monitor. Jour. 15 14-38. McDonald, L.J. 1986. Suspected lead poisoning in an Amazon parrot. Canad. Vet. Jour. 27 131-134. McLean, R.O. and A.K. Jones. 1975. Studies of tolerance to heavy metals in the flora of the rivers Ystwyth and Clarach, Wales. Freshwater Biol. 5 431 -444. 

Arsenic recoveries from the zinc column in the range 0.1-5pg ml-1 arsenic exceeded 97%. The concentrations at which certain elements interfere are shown in Table 12.16. Various other elements [A1 m, B m, Ca II, Cd II, Co II, Cr VI, Fe III, K I, Li I, Mg II, Mn H, Na I, Ni II, Pb II, S VI, Sn II and Zn II] showed no significant interference at the 500pg level. Only low senium concentrations in extracts can be tolerated. However, few environmental samples contain appreciable amounts of selenium. As selenium is not reduced to hydrogen selenide on the column, selenium will not interfere in the final determination step, but probably suppresses either arsenic reduction or arsine formation. Selenium appears to suppress arsine generation at high arsenic concentrations but causes a slight enhancement at low arsenic concentrations (around O.lpg), which could not be traced to arsenic impurities in the selenium standard used. 

Tolerance to heavy metals, specifically mercury and cadmium, has been associated with the induction of kidney metallothionein, a protein rich in sulfhydryl groups which protects by chelation (102). The synthetic antidote dimercaprol, introduced after World War I for arsenic-containing gases, works by a similar mechanism (103). 

Bismuth arsphenamine sulphonate (Bismarsen , Fig. 9) a yellow powder readily soluble in water, was first prepared by Raiziss in 1924 [70]. Stokes and Chambers [71] were the first to use the drug clinically, giving two injections a week for 14 weeks. Four such courses separated by intervals of a fortnight were administered in all. Nevertheless the effects were slow compared with the arsphenamines, although the tonic effect was greater and the side effects less numerous. Relapses, particularly in the central nervous system (CNS) were more frequent. Consequently, Rayburn and Boyd emphasized the fact that some individuals with neurosyphilis who were intolerant to arsenic in any other form could nevertheless tolerate it in the form of Bismarsen [72]. The low toxicity, the tonic effect, and the ease of administration were the chief advantages in favor of Bismarsen . The other compounds of bismuth with arsenic were not extensively tested in humans. 

Li, Y, Dankher, O.P., Carreira, L., Smith, A.P., and Meagher, R.B. 2006. The shoot-specific expression of g-glutamylcysteine synthetase directs the long-distance transport of thiol-peptides to roots conferring tolerance to mercury and arsenic. Plant Physiology, 141 288-98. 

There is evidence that tolerance to this lethal poison can develop. According to a physician, the arsenic eaters of the Styrian Alps in the seventeenth century thrived on a twice-weekly dose of arsenic. It was supposed to improve both their ability to work at high altitude and the women s complexions. The idea was initially ridiculed by scientists, until a peasant demonstrated at a conference that it was possible to eat 400 mg of arsenic trioxide and survive. 

Liu, J., H. Chen, D.S. Miller, J.E. Saavedra, L.K. Keefer, D.R. Johnson, C.D. Klaassen and M.P. Waalkes. Overexpression of glutathione S-transferase II and multidrug resistance transport proteins is associated with acquired tolerance to inorganic arsenic. Mol. Pharmacol. 60 302-309, 2001. 

Collinet M-N, Morin D (1990) Characterization of arsenopyrite oxidizing Thiobacillus. Tolerance to arsenite, arsenate and ferric iron. Antonie van Eeeuwenhoek 57 237-244 Collins MJ, Arciero DM, Hooper AB (1993) Optical spectropotentiometric resolution of the hemes of hydroxylamine oxidoreductase. Heme quantitation and pH dependence of Em. J Biol Chem 268 14655-14662... 

Campbell then sought to call hearings so that the tolerances, if too high, would at least be enforceable. The Industrial Hygiene Division delayed another year until its report was deemed ready for publication. At that point the growers and shippers, happy with the situation as it was, took up delaying tactics. Delay in wartime was easy to obtain, and enforceable tolerances for arsenic and lead were not set until 1950. By that time, it made little difference arsenical pesticides had been eclipsed in importance by new synthetic compounds.14... 

Gloeophyllum trabeum (brown-rot fungus, particularly tolerant to phenolic and arsenic compounds). 

There was extensive human testing, often involving scores of men at a time. Some of the tests were so drastic, one wonders what could possibly have motivated men to go through with them. In 1922, for example, twenty observers were placed in a gas chamber for ten minutes exposure ( the limit of tolerability ) to the arsenic gas DA and suffered... 

Bacterial resistance to arsenic ions governed by plasmids was first discovered by Novick and Roth (17) in a group of Staphylococcus aureus p-lactamase plasmids that determine resistances to antibiotics and also to heavy metals. Arsenic resistance plasmids confer tolerance to both arsenate and arsenite as well as to antimony (III) (18). Resistance to all three ions is inducible and cross-induction among them occurs (18). Arsenic resistance determinants are very common in plasmids of both gram-negative and gram-positive bacteria. 

M-N Collinet, D Morin. Characterization of arsenopyrite oxidizing Thiobacillus. Tolerance to arsenite, arsenate, ferrous and ferric iron. Antonie van Leeuwenhoek 57 237-244, 1990. 

The integrated reaction-separation system was tested for arsenic, selenium and antimony and was shown to provide improved tolerance to interferences due to better conditions in kinetic discrimination, but further refinements appear to be necessary to improve the sample throughput and sensitivities. 

Data on arsenic effects to soil biota and insects are limited. In general, soil microorganisms are capable of tolerating and metabolizing relatively high concentrations of arsenic. This adaptation seems usually to be due to decreased permeability of the microorganism to arsenic. Tolerant soil microbiota can withstand concentrations up to 1600.0 mg/kg however, growth and metabolism were reduced in sensitive species at 375.0 mg As/kg and, at 150.0-160.0 mg As/kg, soils were devoid of earthworms and showed diminished quantities... 

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