Canada's nuclear safety commission authorized Wednesday the restarting of a reactor that produced one-third of the world's supply of medical isotopes before it closed for repairs last year.
The half-century old National Research Universal reactor in Chalk River, Ontario, 185 kilometers (115 miles) northwest of Ottawa, could be restarted at the end of the month.
It was shut down in May 2009 after a leak of radioactive water inside the reactor.
Atomic Energy of Canada Limited (AECL) had initially estimated the stoppage would last only a few months.
Medical isotopes produced by the reactor are used to diagnose cancer and heart disease in patients around the world. The shutdown led to a global shortage of the precious radioactive material.