Concentrations of Radioactive and Stable Caesium in Bone and Soft Tissues

Abstract

The concentrations of both stable caesium and radioactive ¹³⁷Cs have been measured in human tissues from individuals who died in England during 1956 or in the 12 months February, 1960, to February, 1961. The concentration of stable caesium in bone was found to be of the same order as that for soft tissue, viz. 9 to 20 ng/g wet weight. Radioactive ¹³⁷Cs was measurable in only two of the 16 samples of femoral bone, while in liver and muscle the concentration ranged from 0·03 to 0·16 pc/g wet weight. It is estimated that from 2 to 7 per cent of the body caesium (radioactive or stable) is located in calcified bone. If 6 per cent of the total body ¹³⁷Cs is in the skeleton it is estimated that in 1960 the mean radiation dose to bone from ⁹⁰Sr, compared that from ¹³⁷Cs, was about 50 times greater in children and some five times greater in adults.