Know Nuclear



Ions are atoms that are either missing or have extra electrons and so have a charge. Let’s say an atom is missing a neutron or has an extra neutron, that type of atom is called an isotope.

Radioactive isotopes or radioisotopes are isotopes of an element having an unstable nucleus that decays (emitting alpha, beta, or gamma rays) until stability is reached. The stable end product is a nonradioactive isotope of another element. Uranium (U) is a metallic, silver-gray element that is a member of the actinide series. The radioisotope Uranium-238 has 3 more neutrons than Uranium and decays to Lead-206.

Since minute traces of radioactive isotopes can be detected to a high degree of precision, they have various uses in medical therapy, diagnostics, and research. Domestic sources of radioisotopes are needed to adequately sustain the growing use of this technology to ensure our productivity, security and competitiveness and to meet the growing needs of our medical and healthcare communities.

In medical therapy, radioisotopes are used to inhibit or kill specific malfunctioning cells. For example, radioactive phosphorus (P-32) is used to treat abnormal cell proliferation like that occurring in polycythemia (increase in red cells) and leukemia (increase in white cells).

Radioactive iodine (I-131) can be used in the diagnosis of thyroid function and in the treatment of hyperthyroidism. Since the iodine taken into the body concentrates in the thyroid gland, the radioactivity can be confined to that organ.

In research, radioactive isotopes used as tracer agents make it possible to follow the action and reaction of organic and inorganic substances within the body, many of which could not be studied by any other means. They also help to ascertain the effects of radiation on the human body. One out of three patients admitted to hospitals undergo at least one medical procedure that uses radioisotopes, amounting to more than 15 million diagnostic tests and several hundred thousand therapeutic treatments conducted each year.


Promising research, in areas such as cancer, cardiovascular disease and rheumatoid arthritis, has been delayed or abandoned because certain radioisotopes have been unavailable.

Geologists, archaeologists and police rely on radioisotopes to determine the age and chemical composition of materials. Biologists explore the use of radiation in food preservation and in agriculture to develop better fertilizers, control insects and improve plant breeds.

Carbon Dating

If we look at the Carbon-14 atom, we find that C-14 does not last forever. There is a time when it loses its extra neutrons and becomes Carbon-12. The loss of those neutrons is called radioactive decay. That decay happens regularly. For carbon, the decay happens in a few thousand years (5,730 years). Some elements take longer, and others have a decay that happens over a period of minutes. Archeologists are able to use their knowledge of radioactive decay when they need to know the date of an object they dug up. C-14 locked in an object from several thousand years ago will decay at a certain rate. With this knowledge, archeologists can measure how many thousands of years old an object is. This process is called carbon dating.

In industry, radioisotopes provide tracers that allow for inspection and detection of pollutants, gauges that measure precise amounts for better use of raw materials, radiography techniques that identify invisible cracks before they affect bridges, pipelines or heavy equipment.

Radioisotopes sterilize items including cosmetics, medical products and surgical instruments. Safer and cheaper than other methods, radiation sterilizes after an item is packaged and provides for an extended shelf life.

Know Nuclear

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