Strontium

STRONTIUM, Strontium, Sr, an alkaline-earth metal of Group II of the Mendeleev system, atomic number 38, atomic weight 87.63. It occurs in nature in the form of celestine—SrSO₄, strontianite—SrCO₃, and others. Strontium salts are analogous to calcium salts both in their methods of preparation and in their principal properties. The difference from Ca is the solubility of Ca(NO₃)₂ in absolute alcohol and the insolubility of Sr(NO₃)₂ in it; the difference from Ba is the solubility of SrCrO₄ in weak acetic acid. Strontium salts color the flame red. Strontium possesses a significantly weaker antagonistic action relative to magnesium compared to calcium. Although it is deposited in small quantities in the bones of growing animals, dietary calcium cannot be replaced by it. Strontium is excreted mainly by the intestine and to a small extent by the kidneys. Its therapeutic significance is limited, and its salts have no advantages over potassium and sodium salts. The following salts are used: strontium bromide—white hygroscopic crystals, very easily soluble in water (1 : 1) and alcohol; in epilepsy up to 4 g per day. Highest single dose 1 g. The purified salt was used intravenously in fluoroscopy. It was suggested for hyperacidity. Strontium iodide—colorless crystals, very easily soluble in water, rapidly dampening in air and turning brown due to liberated iodine. It is used at 0.5–1 g per dose instead of potassium iodide. Strontium lactate is suggested for albuminuria and nephritis at 0.5 g per dose, and also as an anthelmintic agent. Abroad, a whole series of strontium compounds has recently been proposed for various purposes. Strontiuran—strontium monochloride with urea in a 10% solution; it was recommended without sufficient grounds for urticaria, asthma, hay fever, and as a solvent for salvarsan. Strontisan—salicylic acid strontium—for gout and rheumatism. Strontikol—a protein-phosphorus strontium preparation instead of calcium therapy. Strontianyl and strontiacol—compounds of strontium and barium; for colic in horses. When prescribing strontium salts in solutions, it must be kept in mind that SrCO₃, SrHPO₄, and SrSO₄ are insoluble in water; therefore, one should avoid prescribing strontium salts in the same mixture with carbonic, phosphoric, or sulfuric acid salts (e.g., with soda, codeine phosphate, Glauber's salt, or Epsom salt, etc.). Strontium salts are used in pyrotechnics to produce a red fire. I. Levinstein.