EFFECTS OF FUMONISIN B-1 IN PREGNANT RATS - PART-2

The developmental toxicity of purified fumonisin B-1 (FB1), a mycotoxi n from the common corn fungus Fusarium moniliforme, was examined in Ch arles River rats: Pregnant rats were dosed orally on gestation days 3- 16 at 0, 6.25, 12.5, 25 or 50 mg FB1/kg body weight/day. FB1 was not t eratogenic at the doses tested. At 50 mg/kg, maternal toxicity (inappe tence, emaciation, lethargy, death, resorption of entire litters) and foetal toxicity (increased number of late deaths, decreased foetal bod y weight, decreased crown-rump length, increased incidence of hydrocep halus, increased incidence of skeletal anomalies) were seen. The foeta l toxicity observed at 50 mg/kg may be related to maternal toxicity. H istopathological evaluation of tissues from dams of control and all tr eated groups revealed dose-related toxic changes in kidney and liver t issues. Acute toxic tubular nephrosis was seen in kidneys from all tre ated groups. Hepatocellular cytoplasmic alteration and individual cell ular necrosis of the liver was seen in the two high-dose groups. Sphin ganine (Sa) and sphingosine (So) were measured in day-17 adult and foe tal tissues. Dose related increases in Sa/So ratios were seen in mater nal liver, kidney, serum and brain, but there was no effect on foetal liver, kidney and brain. These data suggest that FBI does not cross th e placenta and further suggest that the observed foetal toxicity is a secondary response to maternal toxicity. (C) 1998 Elsevier Science Ltd . All rights reserved