Metabolism of o-, m- and p-fluoro-, -bromo- and -iodo-nitrobenzenes in the rabbit

Abstract

The metabolism of o-, m- and p-fluoro, o-, m- and p-bromo-and o-, m- and p-iodo-nitrobenzene was studied in the rabbit. The ortho and para compounds form mercapturic acids (over 30% of the dose with the fluoro- and o-bromo-compounds) but the meta compounds do not. Except with p-fluoronitrobenzene (less than 10%) about 30-60% of the dose is excreted as phenols conjugated with glucuronic and sulfuric acids; except with p-bromo- and p-iodo-nitrobenzene (30%) less than 10% of the dose is excreted as the corresponding anilines. The main phenolic metabolite of p-fluoronitrobenzene is p-amino-phenol. o- and m-Fluoronitrobenzenealso probably undergo hydroxyl-defluorination. Apart from hydroxyldehalogenation in the fluoro compounds the metabolic fate of the fluoro-, bromo- and iodo-nitrobenzenes is, in general, qualitatively similar to that of the corresponding chloro compounds.