Long-term oral cadmium produces bone marrow hypoplasia in mice.

Marrow hypoplasia is described in CBA/H mice that drank water containing 300 mg/liter cadmium chloride for 12 months. This was characterized by a significant reduction of the totipotent stem cells (CFU-s), granulocyte-monocyte progenitor cells (GM-CFUc), and erythroid progenitor cells (CFU-e). The bone marrow cellularity and the proliferative capacity of GM-CFUc in vitro were decreased. The animals reflected these marrow alterations by demonstrating an anemia with reticulocytopenia and neutropenia. They did not show increased mortality or increased susceptibility to infections; however, their body weight was significantly reduced. In addition, iron deficiency was demonstrated in the cadmium-treated mice. The animals had a hypochromia of the peripheral red cells and diminished marrow iron stores. Thus, the anemia of cadmium toxicity is probably the combined result of bone marrow hypoplasia and iron deficiency.