Do you think that the USA or any other country should be producing more plutonium?
Plutonium, MOX
Plutonium is a metallic chemical element with the symbol Pu and the atomic number 94. It is radioactive, and used in most modern nuclear weapons. Most plutonium is manufactured, but trace amounts can exist in uranium ores. Contrary to some media reports, plutonium is by no means the most toxic substance known. It is dangerous when inhaled or ingested, however. Its main danger lies in its use in weapons and the risk of a runaway nuclear reactions. Two Los Alamos scientists died in 1945 from radiation due to careless handling of plutonium. Another death occurred in 1958. Other deaths have occurred in other countries. Plutonium can also catch fire, as happened at the Rocky Flats Plant near Boulder, Colorado in 1969.
Plutonium was secretly discovered in 1941 at the Berkeley Radiation Laboratory at the University of California, Berkeley and was produced for the Manhattan Project. After a test bomb was detonated at the Trinity site, a plutonium bomb was dropped on Nagasaki, Japan. Experiments involving the injection of plutonium into humans were carried out by the USA between April 1945 and July 1947 without informed consent.
The isotope Plutonium 239, or 239Pu, is radioactive with a half-life of 24,200 years and is fissile, being used in most modern nuclear weapons. There are many other isotopes of plutonium. Weapons grade plutonium is over 90% 239Pu. The minimum amount of 239Pu needed to achieve critical mass is between 10 kg and 16 kg.
238Pu emits alpha particles and has a half-life of 87 years. It can supply power for devices which need to function without maintenance for a human lifetime, such as the Galileo and Cassini space probes and artificial heart pacemakers (though it is no longer used in new pacemakers).
300,000 kg of plutonium was accumulated by Russia and the USA by 1982. Safe storage or disposal is a major worry, as is nuclear proliferation. About 10 tons have been released as a result of nuclear explosions. One way to dispose of weapons grade plutonium stockpiles would be to convert nuclear power plants from enriched uranium fuel to MOX (mixed oxide) fuel, which is a blend of 239Pu with depleted uranium. The resultant mix behaves similarly to the enriched uranium that many reactors use.
239Pu is usually manufactured in nuclear reactors by exposing 238U (Uranium 238) to neutron radiation which turns some of it into 239U; two beta decays soon produce 239Pu. The 239Pu and the remaining 238U and any other isotopes of other elements are then separated chemically. Reactor-grade plutonium contains at most 80% 239Pu. Whilst a commercial reactor using unenriched uranium can be used to produce uranium, most need to shut down for weeks to change fuel elements, and unsuitable mixes of the isotopes are produced. Such reactors may be shut down more frequently, or have mechanisms for swapping 238U slugs frequently, so the IAEA inspects them frequently. The RBMK and CANDU types of commercial processor can refuel without shutdowns. In designs which cater for refueling like this, it is not possible to fully contain the reactor, which led to the Chernobyl accident being far worse than it might otherwise have been.
Plutonium reactors are usually fast breeder reactors, as they produce more plutonium than they use fuel.
U.S. to resume plutonium 238 production-report
The New York Times reported that the United States intends to resume production of highly radioactive plutonium 238 at the Idaho National Laboratory, saying most of it will be used for secret missions, perhaps to power espionage devices. The process would produce over 50,000 drums of hazardous and radioactive waste. Since production was halted in the 1980s America has imported about 35 pounds (16 kg) from Russia. Plutonium 239, which is hundreds of times less radioactive than plutonium 238, is used in nuclear arms. Inhaling just one speck of plutonium 238 can cause lung cancer.
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