Adult male Sprague-Dawley rats were injected sc with cadmium (Cd, as cadmium chloride) in doses ranging from 1.6 to 152 micromol Cd/kg body weight (body wt). Fourteen days after dosing, animals were evaluated for reproductive damage. Evaluations for each animal included tests, seminal vesicles, and epididymides weights, vas deferens sperm concentration, and human chorionic gonadotropin (hCG)-stimulated serum testosterone concentration. Since 10 to 60% mortality occurred in the two highest dose groups (74 and 152 micromol/kg), no additional evaluations were conducted om these groups. The weights of the tests, seminal vesicles, and epididymides were reduced at least 40 to 50% in groups receiving 16 or 33 micromol Cd/kg while vas deferens sperm concentrations and hCG-stimulated serum testosterone concentrations were essentially zero. Significant depressions in the sperm concentrations and in the hCG-stimulated serum testosterone concentrations were found in animals receiving the two lowest doses (1.6 and 7.4 micromol Cd/kg) although no changes in tissue weights were observed in these animals.