Sexual functions of mice neonatally exposed to DDT or pcb.

Since DDT and PCB occur in milk, young animals may ingest these substances during the critical period of neonatal life; For this reason lactating mice were given injections of DDT or PCB, 50 mg/kg body weight, once a week for four weeks, the first injection being administered on the day of delivery. The reproductive capacity of their young was studied by measuring the frequency of implanted ova. When both the male and the female of a mating pair had been nursed by DDT- or PCB-treated mothers this frequency decreased from 94% in the controls to 79 and 75% respectively. No significant decrease were found when only one of the mated animals in the pair had been nursed by a treated mother.