strontium90yttrium90
Strontium-90 (Sr-90) is a radioactive isotope of strontium with mass number 90. It is produced primarily as a fission product in nuclear reactors and in nuclear weapons tests, and it can persist in the environment for decades. Sr-90 decays by beta-minus emission to yttrium-90 (Y-90) with a half-life of about 28.8 years. The emitted beta particles have a maximum energy of about 0.546 MeV.
Yttrium-90, the daughter nuclide, has a half-life of about 64 hours and decays by beta emission to
Chemically, strontium behaves similarly to calcium, so Sr-90 tends to be incorporated into bone tissue when
Applications and significance: Sr-90 itself has been used as a heat source in some radioisotope thermoelectric
Safety and regulation: Due to its long half-life and bone-seeking properties, handling and disposal of Sr-90