Technetium-99m is a radioactive substance used in the majority of nuclear medicine diagnosis in the world. In addition, to give a more accurate diagnosis of several diseases, such as cardiovascular disease and cancer, nuclear medicine also includes the treatment of cancer. Radioactive substances used in the radiation therapy against cancer include yttrium-90, iodine-131 and phosphorus-32.
Nuclear power stations use uranium as a fuel to produce energy. The heat generated during the fission process, which splits the nucleus of the uranium atom in several smalls parts, is what turns the turbines that will then produce electric energy. According to the U.S. Energy Information Administration, in 2008 nuclear power represented 20 percent of the total generated in the country.
Radioactive materials are used to make sterilizers, smoke alarms and highly-accurate industrial measuring devices. Americium-241, used in home alarms, emits a constant stream of electrically charged particles around it. With smoke in the air, the emission of particles is altered and this sets off the alarm. Radioactive material is also used to make sterilizers, which are used in hospitals and in the food industry.
Also called radiocarbon, carbon 14 is a radioactive isotope produced in the upper atmosphere, before diffusing through the the lower atmosphere as carbon dioxide. As carbon 14 decays with time, American scientist Willard Libby created the method of carbon 14 dating to identify the age of fossils and archaeological materials. It consists of measuring the small quantities of carbon 14 found in the sample, which is later compared with existing similar samples.