Benzene hepatotoxicity

Potential hepatotoxic effects of various brominated benzenes, however, should be considered. Bromobenzene which is a monobrominated compound, is used in various experiments as a model hepatotoxic compound (refs. 9-11). 

The purpose of this study was to compare hepatotoxic effects of monobromo-benzene, 3 dibromobenzene isomers, hexabromobenzene and tetrabromobisphenol A with special attention paid to the dynamics of changes of selected indicators of liver necrosis during acute poisoning. 

In conclusion, the obtained results suggest that the studied compounds differ from the point of view of acute hepatotoxicity. Only 2 and 2 after a single dose result in equal hepatotoxicity, as found previously for monobromo-benzene. The results obtained in part of experiments in which repeated doses were used, suggest the porphyrogenic properties of the compounds. This requires, however, an extended investigation with more specific indicators of such properties. 

The reactions of nucleophiles with benzoquinone and related compounds can also be viewed as Michael reactions. Benzoquinone is one of the reactive metabolites of benzene, a solvent also associated with aplastic anemia (Fig. 8.14). A similar reactive metabolite is responsible for the hepatotoxicity of acetaminophen (Fig. 4.71), the most common cause of acute liver failure however, most of this reactive metabolite is detoxified by reaction with glutathione, and it is only when glutathione is depleted to approximately 10% of the normal level that significant toxicity ensues. 

Benzene hexachloride Hyperexcitability, neurologic disorders, myoclonic jerks, aplastic anemia, hepatotoxicity, neurotoxicity, cerebral seizures... 

Tetrachloromethane (carbon tetrachloride) 77 -21 None Nonpolar compounds Diethyl ether, benzene, petrol, pentane, hexane Reacts with some nitrogen bases hepatotoxic and nephrotoxic traces can affect microanalytical data... 

A study of petrochemical workers exposed to a mixture of benzene (2.13), toluene (2.73), and xylene (3.15), each below its TLV (and total VOCs below all three individual TLVs) produced hepatotoxic effects. No reason for the observed effect was offered, but it was concluded that exposure to low level aromatic hydrocarbon mixtures can cause liver damage. 43 ... 

Coke oven emissions are complex mixtures of hydrocarbons, including benzene and polynuclear aromatic compounds heavy metals including arsenic, beryllium, and cadmium and other particulates and vapors. In a study of coking workers in Taiwan, it was found that liver function profiles were altered by exposures to coke oven emissions and that exposure to even low levels of these emissions was hepatotoxic. The authors of the study suggest that the adverse hepatotoxic effects are caused by a mixture of chemicals rather than by any one identifiable speciesJ36 ... 

All organic solvents represent a health hazard, but some are more harmful than others. Benzene is leukemic, hexane is neurotoxic, and tetiachlo-romethan is hepatotoxic and should be avoided. Diethyl ether is very inflammable and explosive and should be avoided wherever possible. 

A number of simple chemical compounds such as acetaminophen, bromo-benzene, furosemide, methapyrilene (Graham et al. 2008), and thiobenzamide (Ikehata et al. 2008) produce hepatotoxicity, with damage to extrahepatic tissues... 

Historically the first cases attributing chloroform to liver toxicity were described in 1887, 1889 and 1904. The role of carbon tetrachloride and liver injury has been originally described in 1967 and 1973. In general, the understanding of hepatotoxicity is extremely complex, and the reader is referred to the outstanding text by Hyman J. Zimmerman. A typical example of how metabolism and toxicity of a water takes place is the aromatic chemical such as benzene attached to bromine. The effect on the liver has been originally studied by Mitchell in 1975 who have shown that a change in the rate of the metabolism of this compound is required to create its toxic products. While bromobenzene and carbon tetrachloride share a similar place of metabolism in the liver, the toxicity of bromobenzene and carbon tetrachloride are different, since the bromobenzene toxicity is related to the metabolic capacity of the liver, while that of carbon tetrachloride is not. 

Toluene, benzene and xylenes are generally considered to have limited hepatotoxicity.Exposure to xylene is reported to cause mild steatosis. Exposure to a mixture of solvents, inclusive of xylene and toluene have been reported to produce elevated serum bile acids. ... 

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