Uranium

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More information on uranium mining and its impacts you find on an extra page.

Uranium as a chemical element was discovered in 1789 by Martin Heinrich Klaproth while analyzing pitchblende samples from a silver mine. He named the element after the planet Uranus. In the 1800s the only use of uranium was to colour glass and ceramics. 1840 the French chemist Péligot succeeded in producing uranium in metal form. 1896 Henry Becquerel discovered the natural radiation in uranium ore from Joachimsthal. Marie and Pierre Curie 1898 found in the same uranium ore the irradiant elements radium and polonium and formed the term "radioactivity". 1927 for the first time the genetic impact of radioactive rays was detected on Drosophilidae. 1934 Maria Curie dies the aftermath of the radioactive radiation (leukemia). Research by Enrico Fermi lead to uranium as a nuclear weapon and nuclear fuel source. 1938 Otto Hahn discovered together with Fritz Straßmann the uranium's fission and so the theoretic basis of a new energy source enormous extent. With the Manhattan Project in the USA the development of the atomic bomb was forced. 1942 under management of Robert Oppenheimer the first nuclear chain reaction succeeded. In July 1945 the first nuclear explosion took place at the experimental site of Alamogordo in New Mexico (USA). In August 1945 the USA released an atomic bomb on each of the Japanese cities Hiroshima (bomb called "Little Boy" and contained 64 kg of uranium) and Nagasaki (bomb called "Fat Man"). In Hiroshima about 100,000 people died immediately, in Nagasaki about 70,000. 1946 the Soviet Union started uranium mining in the Ore Mountains (D). In September 1949 the Soviet Union tested their first atomic bomb. The atomic arms race started. Lighting four ordinary light bulbs at an experimental nuclear reactor in Idaho Falls 1951 the myth of "peaceful use of nuclear power" was started. 1952 the United Kingdom detonated their first atomic bomb. 1953 US President Eisenhower delivered his historic "Atoms for Peace" speech to the UN envisioning the creation of an international body to promote and control "peaceful use" of atomic energy and to inhibit its use for military purposes. 1954 the first atomic power station worldwide was taken into operation in Obninsk near Moscow (SU). The so-called "peaceful" utilization of atomic power started. 1957 the International Atomic Energy Agency (IAEA) is formed. 1963 the USA and USSR signed a treaty on a partial stop of atomic weapons tests. 526 atomic explosions had taken place on surface by then polluting the environment all-around earth with radioactive fission products of uranium. 1980 more than 17,000 atomic warheads existed on earth. 1985 there are 374 atomic power stations in 26 countries. 1986 in Chernobyl the so far biggest accident in an atomic power station took place. 1986 Mikhail Gorbachev submitted the Soviet proposal to abolish all atomic weapons until the year 2000.[1][2]

Low concentrations of uranium occur naturally in soil, granite and seawater. As uranium decays it provides a major heat source for the earth causing convection and continental drift.[2]



Uranium - A Deadly Material

extract of the homonymous flyer

This is the story of the stages of the uranium chain and gives an overview of the threats connected to each step of the processing of that radioactive material. It starts with the mining of the uranium ore, continues with the conversion of the milled "Yellow Cake" into the gaseous UF6, then it is enriched and, in the next step, the fuel elements are fabricated. After that the uranium is used in nuclear reactors and for nuclear weapons - leaving long-lasting radioactive waste. Each stage of the uranium chain is connected to dangerous transports and the release of huge amounts of carbon dioxide.

There are 92 naturally occurring elements but only one, uranium, has become the key to the operation of the nuclear fuel cycle. This singular use of uranium stems from its unstable, radioactive atomic structure. The safety problems arising from the use of uranium as an energy source stem from this highly radioactive property of uranium and the wastes it produces. The nucleus of uranium-235 has 143 neutrons and 92 protons and uranium-238 has 146 neutrons and 92 protons. The half-life of uranium-235 is 713,000,000 years and for uranium-238 it is 4,500,000,000 years. Uranium-238, unlike uranium-235, rarely fissions. But an uranium-238 atom can capture a neutron to produce a plutonium-239 atom; though, also plutonium-238, -240 and -242 are formed in lesser amounts.

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Uranium-238

Natural decay chain of uranium-238

Uranium-238 is not only radiating itself but also produced a series of radioactive daughter elements which all are existing in the ore. The main problems for the surroundings of the ore are radium and radon, because radium binds easily to soluble substances and will be washed out by rain and goes to ground water. Radon is gaseous und leaves the mineral at open surfaces and is in the air to be inhaled. Its half-life is only short, 3.8 days, but it is continuously produced again by radium.[3]

Table 1 Natural decay chain of uranium-238
Nuclide Half-life Radiation Relative activity
Uranium 238 4,5 x 109 y α γ 100
Th 234 24 d β γ 100
Pa 234m 1,2 m β γ 100
U 234 2,5 x 105 y α γ 100
Th 230 8,0 x 104 y α γ 100
Radium 226 1622 y α γ 100
Radon 222 3,8 d α 100
Po 218 3,05 m α 100
Pb 214 26,8 m β γ 100
Bi 214 19,7 m β 100
Po 214 1,6 x 10-4 s α γ 100
Tl 210 1,3 m β γ 100
Pb 210 22 y β γ 100
Bi 210 5,0 d β 100
Po 210 138 d α 100
Tl 206 4,2 m β 100
Pb 206 stable

The radiations of the nuclides in Table 1 are alpha-, beta- and gamma-rays. Gamma-rays are penetrating matter, they are very similar to x-rays. Beta- and alpha-rays are high energetic particles with electrical charge. All these rays produce mutations in tissues.[3]

Alpha-rays are of high biological effectiveness if they can get into the body via the lungs or into the stomach. Fig.1 shows tracks of single alpha particles sent out by radium. The path length in air is some centimeters, in tissue it would be only 1/1000 of that: some 10 micrometers. They are only dangerous if incorporated.[3]


Finde more articles about Uranium on the Nuclear Heritage Network webpage.


Legal limits for uranium in drinking water


  1. translated from: untitled document from GDR time connected to the WISMUT uranium mine (German)
  2. 2.0 2.1 http://www.visualcapitalist.com/uranium-metal-of-tomorrow as at August 14, 2013
  3. 3.0 3.1 3.2 Prof. Dr. Inge Schmitz-Feuerhake, Hannover, Germany, German Society of Radiation Protection: Health Effects of Uranium Mining in Workers and Residents and the Experience in Germany. Lecture hold at the independent experts' hearing in Ranua on November 7, 2009