In vivo screening of potential antidotes for chronic cadmium intoxication.

Nineteen chelating agents have been screened under identical conditions of metal loading in an attempt to establish their relative ability to mobilize cadmium from the liver and kidney in mice with chronic cadmium intoxication. The compounds investigated were divided into five groups: polyaminocarboxylic acids, monothiols, dithiols, macrocycles, and a miscellaneous category. Only 2,3-dimercaptopropanol (BAL) and sodium diethyldithiocarbamate (NaDDTC) were able to produce a statistically significant (at the 95% level) reduction in the cadmium content of the kidney. The closely related dithiols sodium 2,3-dimercaptopropane-1-sulfonate and 2,3-dimercaptosuccinic acid produced statistically significant increases in the liver cadmium contents, as did N-(2-mercaptopropionyl)-glycine. The reduction in kidney cadmium levels produced by both BAL and NaDDTC was just under 40%.