LACK OF EMBRYOTOXICITY OF FUMONISIN B-1 IN NEW-ZEALAND WHITE-RABBITS

Fumonisin B-1 (FB1) is one of a number of mycotoxins produced by fungi , especially Fusarium sp. As a contaminant of many maize-derived produ cts, this toxin is associated with a variety of animal diseases, inclu ding esophageal cancer and possibly neural tube defects in humans. We have investigated the embryotoxic potential of this compound in New Ze aland White rabbits. Animals were dosed by gavage daily on GD 3-19 wit h purified FB1 at 0.10, 0.50, or 1.00 mg/kg/day. Maternal lethality oc curred at the 0.50 and 1.00 mg/kg/day doses. When examined on GD 29, t here were no differences in maternal body weight, maternal weight gain , maternal organ weights, number of nonlive implantations, and number of malformations. Fetal weight was decreased at 0.50 and 1.00 mg/kg/da y (13 and 16%, respectively); this was true for male and female pups. Fetal liver and kidney weights were also decreased at these doses. Ana lysis of embryonic sphinganine to sphingosine ratios demonstrated no d ifferences between control and treated embryos on GD 20, although thes e ratios were increased in maternal urine, serum, and kidney when comp ared to control animals. These data suggest that FB1 did not cross the placenta and that the observed decreased fetal weight was probably th e result of maternal toxicity, rather than any developmental toxicity produced by FB1.