Fetal uptake and distribution of metallic mercury vapor in the mouse: influence of ethanol and aminotriazole.

The placental transport of mercury in pregnant mice and its localization in the embryo and fetus from early organogenesis through the whole fetal period was studied by whole-body autoradiography and gamma counting. Metallic mercury (203Hg0) (after inhalation) was compared to inorganic 203HgCl2 (after i.v. injection). Hg0 appears to be oxidized to Hg2+ in the fetal tissues and Hg0 inhalation results in about 4-fold higher fetal mercury concentration than Hg2+ injection (9.9 versus 2.4% gram dose per gram tissue). Preadmission to the dams with ethanol or aminotriazole resulted in higher fetal concentrations (especially in the liver) of mercury after inhalation of Hg0 but not after injection of Hg2+. A high placental concentration and accumulation in the corpora lutea of mercury after Hg0 inhalation should be also noted.