Effects of aniline hydrochloride in the mouse bone marrow micronucleus test after oral administration.

Mice are non-responsive to aniline-induced carcinogenicity. However, the present paper shows that aniline hydrochloride induces micronuclei in the bone marrow of male CRH mice 24 h after a single oral dose of 1000 mg/kg (in terms of free base) though not at the lower doses of 400 and 500 mg/kg. No micronucleus inductions was found 48 h after oral dosing. A positive response was also seen 24 h after a single i.p. dose of 380 mg/kg aniline. The high oral dose of aniline needed for micronucleus induction, the presence of micronuclei with abnormal morphology and the large inter-animal variability found within this group may possibly indicate a more complex mechanism of micronucleus induction than simple clastogenicity.