Method for the theoretical determination of the biological half-lives of 137Cs and 90Sr in man, on the basis of K and Ca metabolisms

The formula, used for the calculation is the following: t = ln2/lna+b/a, where t - the biological half-life in days, a - the total quantity of the examined element (K, Ca, Sr, Cs) in the organism, b - the daily need, respectively, the daily average absorbed and accumulated quantity in the body tissues. According to the calculations the average biological half-life in man amounts to approximately 81 days for the K-Cs system, and approximately 1664 days for the Ca-Sr system. (author)