British officials are still puzzled by the use of this poison, the radioactive isotope Polonium 210.

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For example, a radioactive isotope such as nickel-63 releases so-called beta particles a highly energetic form of electrons.

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Today, one of these monitoring stations in Sacramento, California that feeds into the IMS detected miniscule quantities of the radioactive isotope xenon-133.

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In Vermont, legislators voted in February to prevent Vermont Yankee from continuing to operate because of safety fears and recent leaks of tritium, a radioactive isotope of hydrogen.

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There are many different isotopes of carbon and one that we have probably heard of is in the form of carbon-14, known for radio-carbon dating, but where does this radioactive isotope come from?

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The nuke has had its share of scary moments, including a cooling tower collapse, and, more recently, discoveries of leaks of the radioactive hydrogen isotope tritium.

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When the Sun becomes more active, this isotope becomes more abundant along with beryllium, another radioactive element.

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Cesium-137 has a radioactive half-life of about 30 years, and traces of the isotope still persist from above-ground nuclear bomb tests in the 1950s and '60s.

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And this whole topic completely ignores the other, even rarer form of Heliem, the Isotope Helium3, which is formed only as a biproduct of the radioactive decay of the Tritium used in making nuclear missiles.

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