Oral cadmium chloride intoxication in mice: effects of chelation.

In acute oral cadmium intoxication, the immediate target organ is the gastrointestinal tract. In this study, toxic effects following oral administration of CdCl2 to mice by stomach tube included intestinal paralysis, constipation and necrosis of the gastrointestinal epithelia. Tissue damage in liver, kidneys and testes developed in survivors due to the systemic toxicity of absorbed cadmium. Chelation of the Cd2+ ion by STPP, EDTA or DTPA prior to oral administration reduced mortality, tissue damage and whole body retention of cadmium. Other chelators (cysteine, NTA, DDC) only marginally affected the whole-body retention. DDC even enhanced the inhibition of intestinal motility caused by cadmium. DTPA and DDC decreased the relative deposition in the liver and increased the relative renal deposition. DDC also increased the relative cadmium deposition in brain, lung, spleen and testes. Among the chelators tested, DTPA was most efficient in preventing toxic effects of oral cadmium.