SINCE 1828

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strontium 90

noun

Definition of strontium 90

:a heavy radioactive isotope of strontium of mass number 90 that has a half-life of 29 years, that is present in nuclear waste and fallout, and that is hazardous because like calcium it can be assimilated in biological processes and deposited in the bones of human beings and animals

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First Known Use of strontium 90

1952

Medical Dictionary

strontium 90

noun

medical Definition of strontium 90

:a heavy radioactive isotope of strontium having the mass number 90 that is present in the fallout from nuclear explosions and is hazardous because like calcium it can be assimilated in biological processes and deposited in the bones of human beings and animals — called also radiostrontium

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