The world-wide growth in the use of nuclear materials, whether for weapons systems or in peaceful applications, leads to an increasing risk of theft of such materials by organized criminal groups, terrorists or even governments. The major risk lies with the possible theft of plutonium or uranium 233 or 238. Such materials may be stolen from nuclear power plants, uranium enrichment plants, or from the plants which prepare fuel elements for nuclear reactors. The main danger of theft occurs when such metals are moved from one location to another, but materials may also be stolen from the factories themselves.
It is estimated that almost 2.25 million kg of plutonium and enriched uranium are in storage around the world. The Atomic Energy Commission in the USA records losses of as much as 45 kg of uranium and 27 kg of plutonium per year, mostly due to inaccurate inventory taking, but the amounts involved are enough to manufacture more than 10 bombs. An estimated 2 tonnes of plutonium, enough for 400 bombs, is unaccounted for by British authorities.
As a result of the collapse of the former Soviet Union, considerable concern has been expressed regarding the control of nuclear arsenals and the illegal trade in nuclear materials. The disassembly and destruction of the large number of tactical nuclear warheads that Russia has committed itself to destroy by treaty or unilaterally will take years. This process should include the dismantling of an unknown number of warheads which were placed in storage as they ceased to be deployed. These older weapons, with their primitive locks, are an enticing target for seizure by unauthorized groups. Russian authorities reported that during 1993 there were 900 attempts to gain illegal entry to nuclear installations and a further 700 cases of efforts to smuggle materials out of such installations. In 1994 a wagon load of forgotten missiles was discovered by railway workers on a remote railway siding in Siberia. They had been on their way to be dismantled but had been mislaid, apparently due to the negligence of railway staff.
Stanford Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (DSTO) records that a total of about 40 kilograms of weapons-usable uranium and plutonium were stolen from poorly protected nuclear facilities in the former Soviet Union during the 1990s. Most of that material had been later retrieved, two kilograms of highly enriched uranium from a reactor in Georgia was still missing. The database registered 830 incidents of illicit trafficking of radioactive material. The real amount of missing weapons-grade material could be 10 times higher than the official figures. In 2001, the US-sponsored programme to secure nuclear components in the former Soviet Union had locked only one-third of the more than 600 tons of weapons-usable material.