Using thorium could reduce risk of nuclear power
The metal thorium could be a cheaper, cleaner and safer alternative to plutonium and uranium. So why is is not being used in nuclear reactors all over the world?
Professor Carlo Rubbia, from the European Organization for Nuclear Research (Cern), tells the World Service's One Planet why he has been pushing thorium as a nuclear alternative.
Though it was discovered in 1828, the metal has not been developed as a nuclear fuel until very recently when countries such as Russia, India and China started making plans to build reactors that use it.
This, says Professor Rubbia, is because the metal cannot be used to make an atomic bomb, and its potential was never exploited by Cold War scientists in the same way that uranium and plutonium was.