Ben-Gurion University of the Negev engineers have developed a practical technique to "denature" plutonium created in large nuclear reactors and make it unsuitable for a dozen countries that are building reactors - mostly Arab or Islamic states - to produce nuclear arms. However, it will probably not be a significant deterrent against Iran, which has invested in other options as well, such as centrifuges and small reactors designed for plutonium production. Russia claims it is supplying Iran with what it needs to build a reactor - including nuclear fuel - for "peaceful purposes" including power production, but does not want that "bandit" country to develop nuclear weapons. The Beersheba researchers, headed by Prof. Yigal Ronen, think their work could help "de-claw" some countries if nuclear fuel producers - the US, Russia, Germany, France and Japan - agree to put the denaturing additive they have proven effective into all plutonium. However, the BGU nuclear engineer told The Jerusalem Post on Monday that Iran had two other options - the centrifuges like those Iraq had, and small plutonium reactors. "Our work could solve only one part of the problem. The reality is more complicated, and denaturing is not relevant for Iran's other options. Iran would be able to continue to threaten the world with the other two options if the world doesn't stop it," he explained. "When you purchase a nuclear reactor from one of the five countries, it also provides the nuclear fuel for the reactor. Thus if the five agree to insert the additive into fuel for countries now developing nuclear power - such as Bahrain, Egypt, Kuwait, Libya, Malaysia, Namibia, Qatar, Oman, United Arab Emirates, Saudi Arabia and Yemen - they will have to use it for peaceful purposes rather than warfare," said Ronen. Ronen, who worked on the project with Dr. Eugene Shwageraus and master's student Leonid Golyand, was told last month that in May he would receive an honorary doctorate from the Russian Academy of Sciences - the highest honor awarded in Russia to foreign scientists - for his "outstanding scientific achievements." Nuclear fuel used in nuclear reactors has two isotopes of uranium. One is fissionable, while the other is not. The unfissionable component undergoes a number of nuclear reactions, turning some of it into plutonium. The plutonium also includes fissionable and unfissionable components. The amount of fissionable components created in nuclear reactors is enough to be used as nuclear weapons. The BGU engineer, who has been working on this subject for a long time, and his colleagues thought of putting an additive into nuclear fuel that would be composed of a form of americium (Am 241), a basic synthetic element with the atomic number 95. The radioactive metallic element - obtained in 1944 by Glenn Seaborg, who bombarded plutonium with neutrons - is commonly utilized in commercial ionization-chamber smoke detectors, as well as in neutron sources and industrial gauges. Ronen said he had originally worked on neptonium 237 for the purpose of denaturing plutonium, but had "some problems with it" and switched to americium, which is meant for pressurized water reactors (PWRs) such as the one being built in Iran. The BGU scientists have shown that adding americium 241 to nuclear fuel prevents plutonium from being used for nuclear weapons. "Countries that purchase nuclear reactors usually give the spent fuel back to the producer. They wouldn't be able to get new plutonium for weapons if it is denatured, but countries that make nuclear fuel could decide not to denature it for themselves," Ronen explained. He and his team appeared at a scientific conference in Switzerland in October and disclosed the basic achievement to hundreds of participants. However, they have not yet told even the Israeli government, which will read it in the papers on Tuesday. A detailed article about their discovery will appear in a month in the Science and Global Security journal.