Orphan source

From Wikipedia, the free encyclopedia
Jump to: navigation, search

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[edit]

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]
  • 1987 - 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 - Thailand - A defunct cobalt therapy machine was sold to a metal junkyard in Samut Prakan, leading to three deaths.[8]
  • 2000 - Egypt - A source was taken home by an unsuspecting person near Mit Halfa, 15 km north of Cairo Qaluobiya,[9]
  • 2001 - Georgia - Six Soviet era RTG's containing strontium-90 were found near the Inguri River [10][better source needed]
  • 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 1960s.[11]
  • 2010 - Mayapuri, India - An orphan source caused the death of one worker and irradiated seven others in a scrap yard in the Mayapuri radiological accident
  • 2011 - Prague, Czech Republic - A brachytherapy source was found buried in a Prague playground, radiating 500 µSv/h from one metre away.[12][13][14]
  • 2013 - Hueypoxtla, Mexico - A defunct cobalt therapy machine en route to proper disposal was stolen, apparently inadvertently, when the heavy truck transporting it was hijacked.[15]

References[edit]

  1. ^ "NRC: Orphan Sources". Nrc.gov. Retrieved 2014-03-05. 
  2. ^ [1][dead link]
  3. ^ "Casablanca orphaned source, 1984". Johnstonsarchive.net. Retrieved 2014-03-05. 
  4. ^ "Gilan orphaned source, 1996". Johnstonsarchive.net. Retrieved 2014-03-05. 
  5. ^ "Lilo orphaned sources, 1996-1997". Johnstonsarchive.net. Retrieved 2014-03-05. 
  6. ^ "Kingisepp orphaned source, 1999". Johnstonsarchive.net. Retrieved 2014-03-05. 
  7. ^ "Nükleer ihmal". Milliyet.com.tr. Retrieved 2014-03-05. 
  8. ^ "IAEA Bulletin Volume 47, No.2 - Reducing the Risk from Radioactive Sources". Iaea.org. Retrieved 2014-03-05. 
  9. ^ "Meet Halfa orphaned source, 2000". Johnstonsarchive.net. Retrieved 2014-03-05. 
  10. ^ "ECOLOGY WITHOUT NATURE: Hunting for a Source about Hunters and Radiation". Ecologywithoutnature.blogspot.com. 2011-09-11. Retrieved 2014-03-05. 
  11. ^ Baqir Sajjad Syed (2008-07-11). "Containers found with radioactive material". Dawn.Com. Retrieved 2014-03-05. 
  12. ^ ""Radioactive" little cylinder found underground in a park in Podolí". iDNES.cz. 29 September 2011. Retrieved 12 November 2012. 
  13. ^ Motl, Luboš. "Why a small cylinder buried in Prague radiates 500 μSv/h?". Retrieved 12 November 2012. 
  14. ^ Falvey, Christian (29 September 2011). "Passerby stumbles upon radioactive playground thanks to wristwatch". Radio Prague. Retrieved 21 November 2012. 
  15. ^ Will Grant (2013-12-05). "BBC News - Mexico radioactive material found, thieves' lives 'in danger'". Bbc.co.uk. Retrieved 2014-03-05.