Mercuric chloride, toxicity

Naganuma A, Anderson ME, Meister A (1990) Cellular glutathione as a determinant of sensitivity to mercuric chloride toxicity. Biochem Pharmacol 40 693-697... 

Galen, a physician whose views outUved him by about a thousand years, died about 200 AD. He beUeved that mercurials were toxic, and did not use any mercury compound therapeutically. However, as a result of Arabian influence, the therapeutic uses of mercury were slowly recognized by Western Europe. In the thirteenth century mercury ointments were prescribed for treating chronic diseases of the skin. Mercury and its compounds, such as mercurous chloride, mercuric oxide, mercuric chloride, and mercuric sulfide, were used widely from the fifteenth to the nineteenth centuries, and to some extent in the twentieth century. During the first half of the twentieth century, the primary therapeutic uses of mercury included bactericidal preparations, such as mercuric chloride, mercuric oxycyanide, and mercuric oxide and diuretics, such as aryl HgX (Novasural) and mercurated ahyl derivatives (14). 

Fire Hazards - Flash Point Not flammable Flammable Limits in Air (%) Not flammable Fire Extinguishing Agents Not pertinent Fire Extinguishing Agents Not To Be Used Not pertinent Special Hazards (f Combustion Products Heat of fire may cause material to form fumes of mercuric chloride, which are toxic Behavior in Fire Not pertinent Ignition Temperature Not pertinent Electrical Hazard Not pertinent Burning Rate Not pertinent. 

Mercuric chloride, other mercury-containing antibacterials and silver will inhibit enzymes in the membrane, and for that matter in the cytoplasm, which contain thiol, -SH, groups. A similar achon is shown by 2-bromo-2-nitropropan-l,3-diol (bronopol) and iso-thiazolones. Under appropriate condihons the toxic action on cell thiol groups may be reversed by addition of an extrinsic thiol compound, for example cysteine or thioglycollic aeid (see also Chapters 12 and 23). 

El-Begearmi, M.M., H.E. Ganther, and M.L. Sunde. 1980. Toxicity of mercuric chloride in Japanese quail as affected by methods of incorporation into the diet. Poult. Sci. 59 2216-2220. 

Handy, R.D. and W.S. Penrice. 1993. The influence of high oral doses of mercuric chloride on organ toxicant concentrations and histopathology in rainbow trout, Oncorhynchus mykiss. Comp. Biochem. Physiol. 106C 717-724. 

Heisinger, J.F., C.D. Hansen, and J.H. Kim. 1979. Effect of selenium dioxide on the accumulation and acute toxicity of mercuric chloride in goldfish. Arch. Environ. Contam. Toxicol. 8 279-283. 

Koizumi, T. and Y. Yamane. 1984. Protective effect of molybdenum on the acute toxicity of mercuric chloride. III. Chem. Pharm. Bull. 32 2316-2324. 

The inhibition of amino-acid transport has been regarded as the main toxic effect of mercury compounds [82], The biochemical mechanism underlying the inhibition is unclear. In unfertilized sea-urchin eggs an interaction with the amino-acid carrier was found, whereas in fertilized eggs inhibition of amino-acid transport was indirect and might result from an elevation of the Na + content of the egg caused by the inhibition of the Na+ pump [83]. The action on the diffusional process could be mediated by an effect on membrane phospholipids or on membrane proteins, or by interaction with Ca2+ which stabilizes membrane structure. Mercuric chloride in skate liver cells inhibited amino acid transport, decreased Na + /K + -ATPase (adenosinetriphosphatase) activity, impaired volume regulatory mechanisms and increased the permeability of the plasma membrane to potassium [84]. It has been suggested that... 

Oral or parenteral administration of mercuric chloride promotes lipid peroxidation [127-129], possibly via a reduction of glutathione peroxidase activity. However, several studies argue against lipid peroxidation being responsible, at least for the early hours of cell toxicity of mercury [130-133]. 

Adams, P.M., Hanlon, R.T., and Forsythe, J.W. Toxic exposure to ethylene dibromide and mercuric chloride effects on laboratory-reared octopuses, Neurotoxicol. TeratoL, 19(6) 519-523, 1988. 

Mercurous salts are less toxic than mercuric salts, probably as a result of lower solubility. Exposure of human subjects to mercurous chloride (calomel) may result in hypersensitivity reactions. 

Mercury may be present in air in different chemical states such as the elemental form (as a vapour or adsorbed on particular matter) or in the form of volatile mercury compounds (mercury chloride, methyl-mercuric chloride, and dimethyl mercury). Although elemental mercury is only one of the mercury forms which is not as toxic as its organic or ionic forms, analytical determination of elemental mercury is of special importance. Such analysis is used not only for determination of elemental mercury in environment, but also as a method for determination of other forms of mercury after reductive treatment. 

Roderer, G., 1983. Differential toxic effects of mercuric chloride and methylmercuric chloride on the freshwater alga Poterioochromonas malhamensis. Aqu. Toxicol., 3 23-34. 

Another class of fixatives used significantly in the past is mercuric-chloride fixatives. These do not initiate aldehyde linkages, but react with a number of amino acid residues such as thiols, amino groups, imidazole, phosphate and hydroxyl groups. On the positive side, fixation times are short, in the order of five to eight hours. On the negative side, it should be noted that mercuric chloride is highly toxic,... 

Mercuric chloride is highly toxic, and ingestion of 1 g may prove fatal. A postmortem urine sample with a mercury concentration greater than 0.1 jJg/ml is highly indicative of mercury poisoning. 

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