One of the scientists working in the U.S. Manhattan Project, the Italian physicist Enrico Fermi (1901-1954), who used radium and beryllium dust to build a neutron source for the creation of new radioactive materials . Fermi and his team managed the production of radioisotopes of sodium, iron, copper, gold, and many other elements. As a result of work by Fermi, who won the Nobel Prize in Physics 1938, scientists have been able to virtually all versions of radioactive elements to develop. Interestingly, the ideas of radioactivity, fission reactions and fusion reactions collectively represent the achievement of an objective pursued by the medieval alchemists: the transformation of one element into another, especially in the precious base metals. Alchemists, precursor chemicals, it is believed that ordinary metals into gold using various beverages, but an impossible dream. But under the radio-isotopes produced by neutron source Fermi golden era. The "catch" is, of course, that gold was unstable, moreover, energy and human mental effort required to build that far exceed the monetary value of gold itself. Radioactivity in the modern imagination, mostly related to the consequences of nuclear war, or the dangers of nuclear dangers, it seems, are greatly exaggerated, if radioactivity is not always harmful to humans. Examples of applications in medicine as a means of diagnosing and treating thyroid problems, or as a treatment for cancer may actually save lives. It's good that not only radiation but even the variety of harmful radiation, known as ionizing radiation, is not fatal in small doses, as evidenced by the fact that every person on earth is exposed to small amounts of radiation is now and then. Approximately 82% of this comes from natural sources and only 18% of artificial sources. Of course, some people are at higher risk of exposure to radiation than others, for example, miners are exposed to high levels of radon-222 isotope present underground, while smokers much higher radiation of ordinary people due to the polonium-210, lead-210 and radon-222 isotopes in the nitrogen fertilizer used for cultivation of snuff. Nuclear weapons, as most people know, produce a large proportion of the radioactive pollution, but the tests of nuclear weapons has been banned, and although the isotope released in these tests are expected in the atmosphere for about a century, significant health risk for most Americans. (Note that countries tend to follow international protocols may have to perform atmospheric testing despite the prohibitions of proof.) Nuclear power plants, despite the great attention they have received from the media and environmental groups, do not risk it is often claimed: in fact, coal and oil burning power plants are responsible for many radioactive contamination in the United States. This does not mean that nuclear power produces no danger, as the disaster at Chernobyl in the former Soviet Union has shown. In April 1986, an accident at a nuclear reactor in what is now Ukraine killed 31 workers immediately and resulted in the deaths of about 10,000 people and therefore later. The fact that radiation can propagate much had to do with the secret tactics of the Communist government, trying to ignore the problem rather than the area to evacuate. Another danger associated with nuclear radioactive waste. Spent fuel rods and other waste from these factories must be dumped somewhere, but simply can not be buried in the ground, because it is a continuing risk to health will be created by the water supply. Not entirely safe secure storage system was developed, and the problem of waste is an ongoing threat because of the extremely long half life of some of the isotopes. Besides its use in applications related to nuclear energy, isotopes play an important role in dating techniques. The latter may sound like a topic that has something to do with romance, but not: dating techniques involve the use of materials, including isotopes, the age of organic and inorganic materials estimate. Uranium-238, for example, has a half life of 4.47 per 109 years, almost the age of the Earth, in fact, uranium is used dating techniques to age the planet, estimated at