137 Cesium Retention in Mice of Different Ages ∗

Abstract

Summary

Analysis of the retention data of mice of various ages demonstrated that after intravenous injection the retention of ¹³⁷Cs chloride varied as a function both of the age of the animal at the time of injection and of the time since injection. The effective retention of cesium was lowest in the youngest mice, progressively higher for the older mice and then somewhat lower again for very old mice. Moreover, the retention does not change in a uniform manner that can be described by the sum of a series of exponential terms. If the retention is to be described accurately, it is frequently necessary to use a series of discontinuous exponential terms, each of which describes the retention over a limited time span.