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This experimental study was designed to investigate a pattern of lead distribution in various tissues when an individual was exposed to inorganic lead. Sprague Dawley male albino rats weighing 250∼300 g were used for the study. The rats were divided into several groups and 1% lead nitrate solution was administered into abdominal cavity, 0.01, 0.03, 0.05 and 0.07 ml/g of body weight, respectively, to each group of rats. The lead levels in tissues were analyzed consecutively following the administration of the lead by dithizone methods of Keenan et al. Effects of alcohol on lead absorption was also discussed. 1. Lead contents per gram of fresh weight of tissue of normal rats were the highest in spleen and liver, and high in heart and kidney, and the lowest in brain, muscle and blood. The pattern of lead distribution in tissues of rat was similar with that in human. The lead concentrations of normal rats were much higher than those in human tissues. 2. Lead concentrations in spleen and liver increased promptly showing the highest levels 30 minutes or 1 hour following the administration of lead and kept higher levels until 16 hours of observation. The lead concentration in kidney steadily increased until it reached the maximum level at 4 hours after the administration, when the actual lead level per gram of fresh weight of the tissue was much lower than those in liver and spleen. Blood lead concentration reached the highest value 4.35㎍/ml 2 hours following the administration of lead. Even though the actual lead levels in blood is lower than in other tissues, rate of increase was 41 times as high as normal blood levels of rats. 3. It seemed to enhance the rate of lead absorption from the abdominal cavity when the 50% of ethanol was simultaneously administered with lead. 4. As the dosage of lead increased, the rate of lead absorption in each tissue decreased. This suggests that each tissue has its own limitation in the capacity of lead absorption that varies by each tissue.
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