Toxicity of minimal amounts of cadmium to the developing rat lung and pulmonary surfactant.

Pregnant rats were injected subcutaneously with 0, 1, 2, 4 or 8 mg cadmium chloride/kg each day during mid-gestation from day 12-15. Dams were sacrificed on day 21. The treatment resulted in a dose-related increase in prenatal mortality, and decreases in body weight, lung weight and saturated fatty acid containing lecithin content in the fetus but no change in pulmonary sphingomyelin. Although the lowest dose produced no changes in fetal viability, body weight or lung weight, a significant reduction in the amount of saturated fatty acid containing lecithin occurred. Since saturated fatty acid containing lecithin is a major component of pulmonary surfactant, fetuses from CdCl2-treated dams may be subject to respiratory distress postnatally.