"An inspector at the No. 502 Power Plant in the southwestern province of Sichuan discovered 63 pieces of Cobalt-60 and 14 empty lead casings missing in late February, the semi-official China News Service said in a report seen by Reuters on Sunday" "Cobalt-60 produces gamma rays that increase the chances of cancer in those exposed to it, but it can also be used as a medical tracer and to treat various types of cancer and irradiate food. As one of several radioactive materials less closely guarded than uranium or plutonium, experts say it could be used in a so-called "dirty bomb" - a conventional explosive combined with a radioactive material that could spread the harmful material over a wide area." http://www.threegorgesprobe.org/tgp/index.cfm?DSP=content&ContentID=4921