In order to study teratogenecity, fetal toxicity and placental transfer of lead nitrate I rats, single doses of 30~70mg/kg of lead nitrate were administered intraperitoneally to pregnant rats on days 8~16 of gestation(day 1=sperm found).
@ES The results were as follows;
@EN 1. From the fetal toxicity of view, the resorption rate was 3.57~6.90% in control group, but experimental groups showed that 12.00~35.71% for Group 1,20.00~66.67% for Group II and 60.00~91.67% for Group III. So, the resorption rate was
depending on
the lead concentrations and the day on which lead was administered.
2. In case of litter size according to gestation days, there was no significant differences between first half of gestation (8~10 days) ad second half of gestation(12~16 days) in each groups. But, the litter sized of experimental groups were
significantly reduced than that of Control group.
3. From the intrauterine growth of view, the mean values of body weight were 6.03±0.76 g for Control group, 5.58±0.57 g for Group I, 5.52±0.78 g for Group II and 4.97±1.13 g for Group III. But, there was no significant differences between
first
half of gestation (8~10 days) and second half of gestation( 10~16 days), except Group II.
In case of corwn-rump length, the result was similar to that of body weight.
So the body weight and crown-rump were significantly reduced at all dosage levels.
4. There were no external malformations, such as sirenomelia, impreforate anus and absent external genitalia, in this study.
5. In the lead concentrations of maternal tissues, the highest concentration was detected in the liver tissue and the next is kidney and so on.
In case of fetus, lead concentrations significantly increased at all dosage levels, but in case of placenta, lead concentration were detected in only group III.
|