ABSTRACT
The overall expression of toxicity of several xenobiotics can be considered a function of their electrophilic character and their bimolecular reactions with critical cellular nucleophiles. 1 , 2 The electrophilic character could be an inborn property of the molecule as in the case of the quinones treated here or a result of biotransformation as in the case of several aromatic hydrocarbons. The bimolecular reactions with critical sulfur nucleophiles is of main relevance because of the wide distribution and high intracellular concentration of these compounds in the form of high and low molecular weight thiols. 3
