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Japanese Scientists Pursue Safer Plutonium

Japanese scientists are working to create plutonium that could not be used to make nuclear weapons, the Daily Yomiuri reported today (see GSN, June 16).

Researchers at the Tokyo Institute of Technology in 2003 began a five-year study on ways to create plutonium unusable for weapons. The scientists have found that if neptunium and other transuranic elements are mixed into uranium and burned as fuel, the plutonium in the resultant spent fuel consists more of plutonium 238, which is less usable for weapons, than of plutonium 239, according to the Daily Yomiuri. Institute researchers have also praised the process for eliminating neptunium, which is currently disposed of as waste.

However, there are some concerns about the process, according to the Daily Yomiuri. For example, some scientists question whether there is enough neptunium, which is only contained in small amounts in spent nuclear fuel, for the process. In addition, plutonium 238 is dangerous because of the large amount of heat it generates, the Daily Yomiuri reported.

The Tokyo Institute of Technology plans to begin an experiment with U.S. researchers that would involve uranium mixed with neptunium being used as fuel in a nuclear power plant in Idaho, according to the Daily Yomiuri.

“If the experiment is successful, it will be the first step toward making plutonium that can be used for peaceful purposes only,” Tokyo Institute of Technology associate professor Masaki Saito said (Masae Honma, Daily Yomiuri, July 20).

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Country Profile

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This article provides an overview of Japan’s historical and current policies relating to nuclear, chemical, biological and missile proliferation.

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