Balance of Potassium, Rubidium and Cæsium between Japanese People and Diet and Assessments of their Biological Half-Times

Abstract

THE biological half-times of radionuclides of the alkali metals have been determined by several investigators by using laboratory animals and even man; excretion and retention analyses were used following a single dosage of radionuclide for the calculation. These methods, however, are subject to criticism because of the extrapolations of animal data to man and also the use of a single dose for a long-term administration; this is especially the case with cæsium-137, which has been incorporated in man through foodstuffs as a result of world-wide contamination from nuclear weapon testings.