Lead content of tissues of baby rats born of, and nourished by lead-poisoned mothers.

Three groups of Wistar rats (5 males and 5 females in each group) were given zero, 100 mg., and 200 mg. Pb(NO3) 2 per kilogram of body weight per day for 45 days and were mated. The lead feeding was continued throughout the duration of experiments. The blood and urinary lead, blood aminolevulinic acid dehydratase activity, and free erythrocyte protoporphyrin and urinary aminolevulinic acid were measured on these rats at the beginning of the study, at the time of mating, and prior to delivery. The tissues, incuding kidney, liver, heart, and brain of the newborn progeny were analyzed for lead content. The blood lead and aminolevulinic acid dehydratase were also measured (pooled blood). These tissues contained very high amounts of lead when the newborns were killed within half an hour after their birth, a very significant reduction being found after one day with further reduction after 7 days. Kidney and heart contained the highest amount of lead, the levels being dose-related. Three weeks after birth the lead content of tissues rose significantly but blood concentrations remained almost identical to the levels obtained 1 day after birth. There was no evidence of lead accumulation in the brain of the babies...