Cobalt-60: the heart of gamma-radiation sterilization.
Currently, more than three million cubic metres of single-use medical devices are sterilized by gamma radiation each year.  The wide use of this method of sterilization is a result of the lethal effects of ionizing radiation on microbial populations and the penetrative powers of cobalt-60.  This article describes how cobalt-60 is produced and used in gamma-radiation sterilization, and how it is disposed of once it has reached the end of its useful life.  Cobalt-60 sources typically have a life of 20 years, at which point they are returned to the suppliers for re-encapsulation, reprocessing, recycling, or disposal.
Brinston
R M
RM
Nordion International Inc., Kanata, Ontario, Canada.
Norton
J L
JL
D003037:Cobalt Radioisotopes; D004869:Equipment Safety; D005720:Gamma Rays; D006801:Humans; D011850:Radioactive Waste; D013242:Sterilization / Q000295:instrumentation / Q000379:methods*