The U.S. and Russia have surplus weapons-grade plutonium from dismantled nuclear weapons. Canada supports disposal to ensure the plutonium is not used for bombs.
Plutonium is produced as a result of fission in nuclear reactors.
It is not dangerous if handled with care in a contained facility, just as we handle other hazardous chemicals. MOX is a mixed oxide fuel containing one to three per cent plutonium. The fuel consists of ceramic pellets enclosed in metal and assembled into a fuel bundle. Once burned the plutonium in MOX is useless for weapons. Spent MOX fuel is not more hazardous than spent natural uranium fuel.