Strontium 90 has a wide range of medical uses. It is used as a radioactive tracer, allowing it to be followed through a patient to troubled areas. It is also used in radiotherapy on certain types of cancers. Other uses for Strontium 90 have been found in the treatment of certain types of heart disease, as it can be used to unclog arteries, and it has also been used to treat some joint problems, such as rheumatoid arthritis.
Strontium 90 is also used in power generation in nuclear power stations isolated from power lines. These power generators are called Systems for Nuclear Auxiliary Power and are often used in such remote areas as the Arctic and in some spacecraft and weather balloons. The Russian military also makes use of Strontium 90 power generation at its remote areas.
Strontium 90 has a use in metals manufacturing processes. When the exact thickness of a sheet of metal is important, Strontium 90 is used. A sheet of metal is passed under a Strontium 90 isotope, and a certain amount of radiation will pass through it; by measuring this amount, a factory can keep an exact measurement of the thickness of the sheet. Similar processes use Strontium 90 to measure the density of tobacco and silk.
Strontium 90 is also used as a tracer in agriculture. By placing small amounts of the isotope into animal feeds, the digestive systems, metabolisms and the distribution of nutrition throughout the body can all be conveniently followed. This can then be used to see what elements may be lacking from current animal feeds and to learn more about animal physiology.