Transfer kinetics and coefficients of 90Sr, 134Cs, and 137Cs from forage contaminated by Chernobyl fallout to milk of cows

A experiment was conducted to study kinetics, transfer coefficients, and biological half-lives of {sup 90}Sr, {sup 134}Cs, and {sup 137}Cs from feed to milk. A cow was fed a diet containing alfalfa hay contaminated by Chernobyl fallout for 14.5 wk. The time-dependent activity in milk was approximated by a two-compartment model with fast biological half-lives of 2, 0.9, and 1 d and slow biological half-lives of 36.9, 8.7, and 12.4 d for {sup 90}Sr, {sup 134}Cs, and {sup 137}Cs respectively. The transfer coefficients determined in the experiment were 0.0008 d L{sup -1} for {sup 90}Sr, 0.0029 d L{sup -1} for {sup 137}Cs, and 0.0031 d L{sup -1} for {sup 137}Cs. The biological elimination phases of {sup 134}Cs and {sup 137}Cs were described by a two-compartment model while a one-compartment model was proposed for {sup 90}Sr. 18 refs., 4 figs., 2 tabs.