Abstract

Thompson, J. A. (1970).Brit. J. industr. Med.,27, 189-194. Balance between intake and output of lead in normal individuals. The amount of lead ingested by a group of five `normal' individuals for a number of consecutive days was determined; during the same period, the amount of lead which was excreted in faeces and urine was also determined and hence, by difference, the amount of lead retained in the body was calculated. The results showed a wide variation from day to day in the lead content of the food, with a range from 70 μg to 750 μg; the average amount was 274 μg. The lead ingested was almost totally eliminated in faeces and urine; the amount of lead excreted daily ranged from 140 μg to 625 μg with an average of 264 μg. Only about 10 μg on average per day, less than 4% of the average daily intake, was retained. At this rate of retention the lead accumulated would almost wholly account for the `normal' body burden of lead found by tissue analysis.