TRANSMISSION OF RADIOIODINE (I131) TO INFANTS THROUGH HUMAN MATERNAL MILK

Abstract

We recently observed two infants, breast-fed by mothers who were given diagnostic tracer doses of radioactive iodine (I¹³¹) who demonstrated significant thyroid gland concentration of the isotope. The quantity of radioactive iodine in the milk and the quantity taken up by the thyroid gland of these infants suggested an element of danger in the use of radioactive iodine in lactating mothers and warranted a preliminary report of our observations. A survey of the literature on distribution of radioactive iodine in tissues did not reveal any instance of radioactive iodine activity in the milk of lactating human beings or transmission to the thyroid gland of nursing infants. Such transmission might have been anticipated from the animal experiments of Rugh¹ and Courrier and his co-workers,² who demonstrated sizeable uptakes of radioactive iodine by suckling mice and rabbits following intraperitoneal injection of radioactive iodine in nursing mothers, and the writings