Inhibition of erythropoiesis by benzene and benzene metabolites

Mice were injected sc with benzene or one of its metabolites, phenol, catechol, or hydroquinone. The ability of these compound to inhibit erythropoiesis was quantified by measuring the incorporation of ⁵⁹Fe into developing erythrocytes. Benzene decreased ⁵⁹Fe incorporation into developing erythrocytes in a dose-dependent manner. Maximum inhibition was observed when benzene was administered 48 hr prior to initiation of the ⁵⁹Fe uptake test. The three metabolites of benzene also significantly inhibited ⁵⁹Fe incorporation when they were administered 48 hr prior to initiation of ⁵⁹Fe uptake assay. The degree of inhibition observed with the metabolites was not as great as that observed with benzene. Coadministration of the microsomal mixed-function oxidase inhibitor, 3-amino-1,2,4-triazole, abolished the erythropoietic toxicity of benzene and phenol but had no effect on the catechol- or hydroquinone-induced toxicity.