Walter E Cabrera, Iris Schrooten, M. de Broe
May 1, 1999
Citations
3
Influential Citations
149
Citations
Quality indicators
Journal
Journal of Bone and Mineral Research
Abstract
STRONTIUM (Sr; MW 87.62) is ranked fifteenth in the order of the elemental crustal abundance in which it occurs at a concentration of 450 mg/kg. The element was first isolated in an impure form in 1808 and named after “Strontian,” a Scottish town where it was found at high concentrations in calcareous rocks consisting of natural apatites in which strontium may occur at concentrations as high as 73 g/kg. In ocean water, strontium is the most abundant trace element, reaching values of up to 8 mg/l. Natural water sources, such as rivers, springs, and wells, contain smaller amounts of the element ranging from 0.021 mg/l up to 0.375 mg/l. Strontium is a natural constituent of food and beverages. Meat, poultry, vegetables, and fruit contain relatively low amounts of the element (range 0.3–5.1 mg/kg), whereas in cereals, grains, and seafood it may be present at concentrations of up to 25 mg/kg. Hence, the strontium content of the human diet and the daily intake of the element varies according to the geographic area and the type of food consumed. A limited number of the series of radioactive strontium isotopes have been applied to the fields of medicine, biology, and biochemistry. The therapeutic potential of intravenously administered strontium-89 was first recognized in 1940 with the discovery that it could be used for the treatment of bone pain from metastatic prostate cancer. The latter isotope, as well as strontium-85 and strontium-88 have been primarily used as markers of calcium metabolism. Research on the toxicity of strontium has so far been focused mainly on the biological effects of radioactive strontium-90, which is an important constituent of nuclear fallout. At that time dietary supplementation of stable strontium was reported to inhibit the intestinal absorption of strontium-90, thereby serving as a deterrent to ingestion of radioactive strontium. However, caution was warranted with these preventive measures since replacement of dietary calcium with strontium was found to result in diminished growth, improper bone mineralization, and an inhibition of intestinal calcium absorption.