Which radio isotope is used for treating bone cancer?

Sr 89 is a sho lived aificial isotope which is used in the treatment of bone cancer. In cancer patients with widespread bony metastasis, administration of Sr 89 results in the delivery of radioactive missions to the site of increased bone turnover. Sr 90 is a byproduct of nuclear fission which is found in nuclear fallout. This isotope is one of the best long lived high energy beta emitters known and is used in Systems for nuclear auxillary power devices.