Teratogenic effect of maternal zinc deficiency and its co-teratogenic effect with cadmium.

The teratogenic effects of feeding pregnant mice with the levels of zinc that were severely deficient (0.5 ppm), marginally deficient (10 ppm), or zinc replete (50 ppm) were studied. All groups of animals were fed the experimental diet from 1-18 days of gestation (dg) except for one additional group which received 0.5 ppm Zn diet from 5-14 dg. The effects of a single dose of 2.0 mg/kg of cadmium chloride (CdCl2) injected on 8 dg in mice fed the marginally zinc-deficient or the zinc-replete diets were also investigated. We found that more than 95% of fetuses exhibited a variety of external and skeletal malformations in the severely zinc-deficient groups and that the frequency of malformed fetuses in the marginally zinc-deficient group was similar to that of the control animals. Injection of CdCl2 produced a significant increase in the incidence of malformations in the marginally zinc-deficient mice, but not in zinc-replete animals. These results demonstrate that severe zinc deficiency is teratogenic in mice and that a marginal zinc intake influences the teratogenic potential of cadmium.