Orphan source
An orphan source is a self-contained radioactive source that is no longer under proper regulatory control.
The United States Nuclear Regulatory Commission defines an orphan source more exactly as:[1]
...a sealed source of radioactive material contained in a small volume--but not radioactively contaminated soils and bulk metals--in any one or more of the following conditions
- In an uncontrolled condition that requires removal to protect public health and safety from a radiological threat
- Controlled or uncontrolled, but for which a responsible party cannot be readily identified
- Controlled, but the material's continued security cannot be assured. If held by a licensee, the licensee has few or no options for, or is incapable of providing for, the safe disposition of the material
- In the possession of a person, not licensed to possess the material, who did not seek to possess the material
- In the possession of a State radiological protection program for the sole purpose of mitigating a radiological threat because the orphan source is in one of the conditions described in one of the first four bullets and for which the State does not have a means to provide for the material's appropriate disposition
Orphan source incidents
Most known orphan sources were, generally, small radioactive sources produced legitimately under governmental regulation and put into service for radiography, generating electricity in radioisotope thermoelectric generators, medical radiotherapy or irradiation.[citation needed] These sources were then "abandoned, lost, misplaced or stolen" and so no longer subject to proper regulation.[2]
For example, in different incidents, various orphan sources have been:
- 1984 - Morocco - A source was lost during radiography and taken home by other people who initially failed to recognize the source [3]
- 1985 - Praça Cívica, Brazil - A caesium-137 based teletherapy unit left behind at Goiânia’s Instituto Goiano de Radioterapia (IGR)[3]. This is one of the most disastrous orphan source incidents, the event is known as the Goiânia accident.
- 1996 - Gilan, Iran - A source was temporarily lost during radiography at a power plant and found by an unsuspecting worker who put the source in his chest pocket for about 90 minutes. 1 person was severely injured [4]
- 1997 - Tbilisi, Georgia - The Lilo Training Center had multiple sources dating back to Soviet era military activity; 11 were injured. [5]
- 1999 - Leningrad, Russia - Stolen from an RTG in a Russian lighthouse and then recovered 50 kilometres away at a bus station [6]
- 1999 - Istanbul, Turkey - A source was sold to a junkyard for its lead container in the city of İkitelli [7]
- 2000 - Egypt - A source was taken home by an unsuspecting person near Mit Halfa, 15km north of Cairo Qaluobiya, [8]
- 2001 - Georgia - Six Soviet era RTG's containing strontium 90 were found near the Inguri River [9]
- 2008 - Karachi, Pakistan - An orphan source was discovered within the vicinity of the OGDCL (Oil & Gas Development Company Limited). Two containers were found buried which were suspected to be left over from Soviet oil drilling operations before the OGDCL took over in late 60s. [10]
- 2010 - Mayapuri, India - An orphan source caused the death of one worker and irradiated seven others in a scrap yards in the Mayapuri radiological accident
References
- ^ NRC: Orphan Sources http://www.nrc.gov/materials/miau/miau-reg-initiatives/orphan.html
- ^ http://www.irlgov.ie/committees-29/c-environment/20030923-J/Page1.htm
- ^ Casablanca orphaned source, 1984
- ^ Gilan orphaned source, 1996
- ^ Richard Stone (European news editor for Science), "The Hunt for Hot Stuff", Smithsonian v33 n12, March 2003, p. 58 [1] ]
- ^ Kingisepp orphaned source, 1999
- ^ Nuclear Negligence, 1999
- ^ Meet Halfa orphaned source, 2000
- ^ Richard Stone (European news editor for Science), "The Hunt for Hot Stuff", Smithsonian v33 n12, March 2003, p. 58 [2] ]
- ^ [3]