Critical concentration of 'unbound' cadmium in the rabbit renal cortex.

Critical concentration of 'unbound' cadmium in the rabbit renal cortex was around 13 micrograms Cd/g, which was far lower than the critical concentration of 'total' cadmium in the renal cortex, 200-300 micrograms Cd/g, and a little lower than the critical concentration of non-MT-Cd in the renal cortex, 35-60 micrograms Cd/g, respectively. The above result may suggest that it is necessary to identify the chemical form of 'active' cadmium in the renal cortex.