Lack of micronuclei induction by fumonisin B1 mycotoxin in BALB/c mice

The genotoxic potential of fumonisin B-1 (FB1) in vivo in BALB/c mice (male and female) was assessed by induction of micronuclei (MN) formation in bone marrow polychromatic erythrocytes. The ratio of polychromatic erythrocytes to normochromatic erythrocytes (PCE/NCE) was also determined. Mice were injected intraperitoneally (i.p.) with FB1 at a low dose (0.1 mgkg(-1) body mass), middle dose (1.0 mgkg(-1) body mass) and high dose (10 mgkg(-1) body mass) as single and multiple doses in normal saline to test the genotoxicity. Mitomycin C, a known clastogen, was used as positive control. The frequency of MN and the PCE/NCE value in animals treated with FB1 at low, middle, and high doses in single dose studies, and the frequency of MN in multiple dose studies, were statistically non-significant from that of the controls injected with saline only. The multiple dose studies at all doses revealed that the PCE/NCE value was found to be reduced upon exposure to FB1 as compared to the controls. In animals injected with multiple low doses of FB1, the PCE/NCE value was found to be 0.66 in males and 0.82 in the females; at multiple middle doses the value was 0.30 in males and 0.41 in the females and was statistically significant (p<0.001); however, at multiple high doses, the ratio was found to be 0.36 in both males and females. The present study confirms that FB1 is non-genotoxic in nature while the reduced ratio of PCE/NCE suggests the cytotoxic nature of FB1.