Lack of clastogenic activity of aniline hydrochloride in the mouse bone marrow

Aniline has been reported to be positive in the mouse bone marrow micronucleus test. This finding is inconsistent with its lack of carcinogenicity in this species. Micronuclei can arise by mechanisms that do not involve direct interaction with DNA, e.g. induction of aneuploidy or stimulation of erythropoiesis. However, clastogenic materials would be expected to demonstrate an increased level of chromosomal damage in dividing precursor erythroblasts. In the present study we have investigated the ability of aniline HCl to induce chromosome aberrations in bone marrow metaphase cells. No evidence of clastogenicity was observed in this study. This suggests that the activity seen in earlier micronucleus assays may have arisen by a mechanism not involving direct DNA interaction. Aniline is known to be toxic towards the erythropoietic system and the possibility exists that micronuclei may be produced as a result of this toxicity.