Transfer of Cs-137 from food into milk of breast-feeding women

Between May 1987 and May 1988 a duplicate of the food taken in as well as a specimen of the milk of 8 nursing mothers was daily collected during 3-4 weeks and the Cs 137 activity was measured. Moreover the mothers' whole-body activity was measured once during the collection period. The measured values show that apart from the direct transfer of Cs 137 from the food taken in into the breast milk a transfer of cellular Cs 137 from the mother's body into the breast milk is also taking place. During this process about 12% of the mother's Cs 137 activity concentration and about 19% of the Cs 137 activity daily taken in with the food are transferred into one liter of breast milk. (orig.)