Breast-milk radioactivity after 99mTc-MAA lung studies.

The concentration of radioactivity in the breast milk of four nursing mothers who had received injections of 99mTc macroaggregated albumin (MAA) was measured. The results were compared with previous measurements, and an estimate of the radiation dose to an infant from internal and external sources was obtained for various times of recommencement of breast feeding. It is suggested that feeding can recommence earlier than the normally recommended 24 h if this is thought to be clinically desirable.