Studies on the Relation between the Excretion of Sr and the Intake of Ca (Report 1)

Abstract

This experiment was attempted to know how to prevent or reduce the effect of contamination by radioactive substances by fallout. There are many kind of radioactive substances in the fallout, and above all 90Sr and 137Cs seem to be most important.As it has been indicated that the behaviour of Sr in and out of our bodies is very close to that of Ca, the experiment on the relation between the Ca content of diet and the excretion of Sr was performed by using albino rats.Experimental: Adult albino rats weighing about 200g were subjected to this experiment, and they were divided into four groups, the Ist group was fed with a high Ca diet and the 2nd a low Ca diet during experimental period, and the 3rd was fed with these high and low Ca diets alternately for 6 days each during this experiment. 90Sr was injected into the abdominal cavity of the rat, 1.3μc per capita. The 4th group was fed by standard diet and 90Sr was injected together with relatively large amount of non-radioactive Sr.Results: The percentage of total excretion 90Sr during 24 days of the Ist, 2nd and 3rd groups were 15%, 8%, 14% respectively, and of the 4th group was about 25% during 18days. The amount of excretion of 90Sr of high Ca diet group was superior to that of the low Ca diet group, and that of the group non-active Sr injected was the highest of all.