One group of rabbits were injected intraperitoneally with diethyllead dichloride (7.7 mg Pb/kg) and another group of rabbits were likewise injected with an equivalent lead dose of lead acetate. These rabbits were followed up for changes in the lead amounts excreted daily in the urine and feces from 24 h through 7 d after the injection, respectively. In the group of rabbits injected with diethyllead dichloride (one of 3 rabbits died during the observation), an amount of lead equivalent to about 25% of the injected dose was excreted in the urine during the first 24 h after the injection. Also, an amount of lead equivalent to about 28% of the injected lead was excreted in the feces during the first 3 d, and the total lead excretion during the 7 d after the injection corresponded to about 60% of the injected dose of diethyllead. One day after dosing, the total lead in the urine was made up of about 92% diethyllead, about 7% inorganic lead and about 1% triethyllead. One day after dosing, the total lead in the feces consisted of about 63% inorganic lead, about 28% diethyllead and about 9% triethyllead. Three days after dosing, the total lead in feces comprised about 98% inorganic lead, about 1% diethyllead and about 1% triethyllead. In the group of 3 rabbits injected with lead acetate, the total lead amount excreted in both the urine and feces during the 7 d after the injection corresponded to only about 9% of the injected dose of lead acetate.(ABSTRACT TRUNCATED AT 250 WORDS)