Relationship between turnover of cesium-137 and dietary potassium content in potassium-restricted mice

The biological half-life of Cs-137 and its organ distribution were investigated in mice fed various potassium-deficient diets, The biological half-life, which was 6.1 days in mice receiving the normal level of potassium, became longer as the dietary potassium content decreased, and Cs-137 was hardly excreted from the body when dietary potassium content was restricted to 200 mg/kg or less, The muscle showed the highest concentration of Cs-137 in both mice that had sufficient amounts of potassium and those that were potassium-deficient. Clearance of Cs-137 from tissues was generally suppressed when mice were fed a potassium-deficient diet, but the relative distribution pattern of Cs-137 was not affected by dietary potassium content. These results suggest that dietary potassium intake, which may vary with eating habits, affects the biological half-life of Cs-137 in humans. (C) 1997 by Radiation Research Society.