Different patterns of mutagenicity of arenediazonium ions in V79 cells and Salmonella typhimurium TA102 : evidence for different mechanisms of action

The edible mushroom Agaricus bisporus contains several arylhydrazines and arenediazonium ions that are genotoxins. The mechanism whereby arylhydrazines and arenediazonium ions are genotoxic is unknown and may be due to the arenediazonium ion itself or to aryl radicals. The reactions of four arenediazonium ions (p-X-C 6 H 5 N 2 + , X = -CH 3 , -CH 2 OH, -CH 2 OCH 3 , -CO 2 H) with purine bases, their mutagenicity, their ability to cause DNA damage, and their tendency toward free radical formation have been studied to elucidate the genotoxic species. It is suggested that either the arenediazonium or aryl radical can act as the ultimate genotoxin. Which species is dominant is dependent upon the arenediazonium ion reduction potential. This relationship may be useful in designing future studies of arenediazonium ion genotoxicity.