Some Radiation Information

Radiation Primer

Some revelant definitions and information:
A Sievert is a measure of radiation exposure, a millisievert is one-thousandth of a sievert, and a microsievert is one-millionth of a sievert.

Isotope: An atom with a particular neutron count in its nucleus. Whereas all the atoms of a given element will have the same number of protons present in the nucleus, the number of neutrons may vary. For example, hydrogen has one proton in its nucleus. It has three different isotopes: protium (most common form containing no neutrons), deuterium (one neutron), and tritium (two neutrons).

Iodine-131 and Cesium-137 are the most dangerous contaminants of concern so far. Iodine-131 is readily absorbed by the thyroid gland and can lead to thyroid cancer. By taking potassium iodide, one can saturate one's thyroid and effectively prevent the uptake. Since the half-life (the time it takes for half of the material to decay) of I-131 is only 8 days, this is an effective and practical method of reducing one's risk. In the case of Ce-137, however, the half-life is about 30 years and there is no effective means of reduction of risk other than physically preventing exposure. Cesium is incorporated in one's bones, primarily and can lead to bone cancer and leukemia.
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