STUDIES OF INHIBITION OF INTESTINAL ABSORPTION OF RADIOACTIVE STRONTIUM. IV. ESTIMATION OF THE SUPPRESSANT EFFECT OF SODIUM ALGINATE.

A method is reported which permits selective suppression of absorption of radioactive strontium from ingested food material, allowing calcium to be available to the body. Studies were carried out on the inhibitory effect of various amounts of sodium alginate and the dose-response relationship of Sr(89) and bone uptake. The results obtained indicated that under laboratory conditions sodium alginate effectively reduces Sr(89) uptake in a constant proportion. This effect was observed at the three levels of administration of 1.4%, 12% and 24% of sodium alginate. The linear relationship between the dosage of the radioisotope and the bone uptake in the presence of sodium alginate suggests that the same proportion is maintained at the lower levels of intake of radioactive strontium.Previous studies with small constant doses of sodium alginate were extended in rats to a period corresponding approximately to three years of human life span. Low doses were sufficient to reduce appreciably bone uptake of radiostrontium.