Strontium and Calcium in Municipal Water Supplies

attention given to the radioactive isotopes of the element strontium has intensified greatly in recent years. These isotopes, Sr89 and Sr90, are among the most potentially hazardous of the products of nuclear fission. This is true by virtue of their ease of absorption from contaminated food or water, their prolonged retention in the human skeleton, and their ability thus to impair the blood-forming functions of bone marrow and to induce bone tumors. Municipal water supplies conceivably might become contaminated with radiostrontium, as well as with other fission products, by fallout from bomb detonations, by deliberate contamination in radiological warfare, or by accidental spills and waste discharge from nuclear reactors. The expanding atomic-energy industry is producing large quantities of radioactive materials, the processing, use, storage, and disposal of which pose new problems to sanitary engineers concerned with water pollution. The purpose of the work reported here was to determine the concentrations of natural, nonradioactive strontium in the waters provided for human consumption by cities throughout the United States. By examination of the raw and tap water of a city, the removal of natural strontium by the particular water treatment applied could be estimated. This information would aid in the evaluation of conventional water treatment practices with regard to their potential effectiveness in removing dissolved radioactive strontium. In addition, the values for natural strontium in potable waters were needed in estimating the average daily intake of natural strontium by humans. Such data on natural strontium and calcium are of aid in attempting to predict the behavior of radioactive strontium isotopes in the human body. In an effort to extract as much infor-