26 Mars 2016
March 22, 2016
Materials that can be used to make nuclear weapons, such as plutonium and highly-enriched uranium, are controlled by international regulations.
That's to prevent them from being used for military purposes by countries other than the 5 nations that are allowed to possess such weapons under the Nuclear Non-Proliferation Treaty.
The 2001 attacks in the United States raised concerns about nuclear materials falling into the hands of terrorists. The international community has been taking steps to tighten nuclear security.
As part of counterterrorism measures, the US proposed that nuclear materials produced by power generation around the world should be collected.
Japan agreed to transfer plutonium to the US at the 2014 nuclear security summit in the Netherlands. The US praised the decision, saying this would increase the level of Japan's nuclear security, which is said to be weak.
Japan currently has 47 tons of plutonium produced by reprocessing spent fuel. The amount is said to be enough to produce nearly 6,000 atomic bombs.
It also accounts for about 17 percent of the 271 tons of worldwide stocks of civilian-use plutonium from reprocessed fuel. Japan's amount is the 4th largest, after Britain, France and Russia.
The international community is critical of Japan, saying the country had promised not to possess more plutonium than necessary.
Japan's stock is expected to rise further, as a fast-breeder reactor that burns plutonium is still under development, and is unlikely to go into use in the near future.
An additional 8 tons a year would be produced after the reprocessing plant now under construction in Rokkasho Village in the northern prefecture of Aomori goes into full operation.