Organomercurial toxicity

DIFFERENTIAL EFFECTS OF SODIUM SELENITE AND METHYLMERCURY(II) ON MEMBRANE PERMEABILITY AND DNA REPLICATION IN HeLa S3 CARCINOMA CELLS A PRELIMINARY REPORT REGARDING THE MODIFICATION OF ORGANOMERCURIAL TOXICITY BY SELENIUM COMPOUNDS... 

SELENIUM COMPOUNDS AND ORGANOMERCURIAL TOXICITY RESULTS AND DISCUSSION... 

The acute toxicity of different types of organomercury compounds to mammals,... 

Eaton and co-workers also reported the synthesis of 1,3,5-trinitrocubane and 1,3,5,7-tetranitrocubane (39) ° The required tri- and tetra-substituted cubane precursors were initially prepared via stepwise substitution of the cubane core using amide functionality to permit ort/jo-lithiation of adjacent positions. The synthesis of precursors like cubane-1,3,5,7-tetracarboxylic acid was long and inefficient by this method and required the synthesis of toxic organomercury intermediates. Bashir-Hashemi reported an ingenious route to cubane-1,3,5,7-tetracarboxylic acid chloride (35) involving photochemical chlorocarbonylation of cubane carboxylic acid chloride (34) with a mercury lamp and excess oxalyl chloride. Under optimum conditions this reaction is reported to give a 70 8 22 isomeric mixture of 35 36 37... 

Since the 1950s, diuretic therapy has changed dramatically. Earlier, the major diuretics were acidforming salts, xanthines, organomercurial compounds, and carbonic anhydrase inhibitors. Either because of toxicity or lack of efficacy, these agents are rarely if ever used. 

Mercury is mined predominantly as HgS in cinnabar ore and is then converted commercially to a variety of chemical forms. Key industrial and commercial applications of mercury are found in the electrolytic production of chlorine and caustic soda the manufacture of electrical equipment, thermometers, and other instruments fluorescent lamps dental amalgam and artisanal gold production. Use in pharmaceuticals and in biocides has declined substantially in recent years, but occasional use in antiseptics and folk medicines is still encountered. Thimerosal, an organomercurial preservative that is metabolized in part to ethylmercury, has been removed from almost all the vaccines in which it was formerly present. Environmental exposure to mercury from the burning of fossil fuels, or the bioaccumulation of methylmercury in fish, remains a concern in some regions of the world. Low-level exposure to mercury released from dental amalgam fillings occurs, but systemic toxicity from this source has not been established. 

In the 1930s, the use of organomercurial fungicides became popular primarily as seed treatments but it has since been banned because of its high toxicity and persistence in the environment. 

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