Predicting the retention of Cs in individuals

Various factors have been offered to explain and/or predict the wide variation in the retention of Cs among humans. For example, the biological half-time of Cs has been expressed as an increasing function of body mass and also as an increasing function of age throughout life. Some early investigators attempted to describe accumulation of Cs in the body in terms of discrimination factors between Cs and the chemically similar element K, but such factors were found to oversimplify the relation between Cs and K and they were soon abandoned. In this paper it is shown that K may be a useful index, after all, for predicting the retention patterns of Cs in individuals. A predictive model for individuals is constructed, using observed relationships between the mass of total-body K (Kt) and the parameters in the standard two-exponential retention model for Cs.