Radiological Dispersal Devices (RDDs)

The Issue | Obstacles | Q & A | Quick Facts | Legislation | Agreements | Talking Points | Recommendations

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The Issue

A radiological dispersal device (RDD), or "dirty bomb," uses conventional (non-nuclear) explosives to spread radioactive material. The damage caused by the detonation of an RDD can range from relatively minor to catastrophic, depending on the type of material used and the size of the explosion. Even if the explosion does not cause extensive loss of life, the potential consequences can be extremely serious in terms of mass panic, economic disruption, and the need to vacate and decontaminate the area. A dirty bomb is considered useful to terrorize a populace or to deny the use of the affected area, without resorting to mass killings.[1]

According to one analysis, an explosion in lower Manhattan dispersing powdered cesium-137 could contaminate roughly one quarter of the island to a level above the relocation threshold recommended by the International Commission on Radiological Protection.[2] The area would be rendered uninhabitable for months to years, depending on the material used and the area covered.

Dirty bombs are attractive to terrorists because the materials necessary to build the weapons are relatively easy to acquire and the technology is simple. Materials with the potential for serious attacks are used in hundreds of medical, industrial, and academic applications, including "destroying bacteria in food, sterilizing pharmaceutical products, killing cancer cells, inspecting welds, exploring for oil, and doing research in nuclear physics and engineering."[3] These materials include isotopes such as cobalt-60, cesium-137, americium-241, strontium-90, iridium-192, and plutonium. According to the International Atomic Energy Agency (IAEA), "Millions of radioactive sources have been distributed worldwide over the past 50 years, with hundreds of thousands currently being used, stored, and produced."[4] Even states with relatively strong security measures in place face significant challenges in preventing the diversion of radioactive materials; these materials, either through malevolence or human error, do get stolen or lost. Over 100 states have been found to have inadequate controls over these dangerous materials.[5]

According to Dr. Henry Kelly, President of the Federation of American Scientists, security systems for potential RDD materials work "reasonably well when the owners have a vested interest in protecting commercially valuable material. However, once the materials are no longer needed and costs of appropriate disposal are high, security measures become lax, and the likelihood of abandonment or theft increase."[6] There is an urgent need to determine the extent to which security can be heightened, which materials require immediate attention, and how to carry out a program to implement safety improvements. Since September 11, 2001, the Nuclear Regulatory Commission (NRC) and US state governments (some of which have agreements with the NRC to license organizations that use radioactive material) have attempted to enhance material security in the US.[7]

The problem of security is even more serious abroad. In January 2001, for instance, three woodcutters in the Republic of Georgia found two abandoned cans of strontium-90 and used the material to keep warm; all three were critically injured.[8] Between 2001 and 2004, twenty-nine different orphaned radioactive sources have been found in the southwest Russian republic of Chechnya.[9] An unknown number of dangerous sources still exist in the war-torn republic.[10] Approximately 1,000 radioisotope thermal generators, power sources for facilities like lighthouses and weather stations, are in numerous remote sites in Russia that are vulnerable to terrorists.[11]

Keeping these materials out of terrorists' hands is an immense and important challenge.

Recent Action

The US Government has organized several programs aimed at reducing the threat of radioactive materials. The NRC sets standards for the protection of these materials in the US and requires all American entities that work with radioactive sources to have a valid license. The NRC also provides information to nuclear facilities around the world, as well as to the IAEA. The Department of Energy contributes with two overarching programs focused on radioactive sources. The US Radiological Threat Reduction program, created in 2003, consolidated radioactive source security programs throughout the Department of Energy into one office. Primary among these programs is the Off Site Source Recovery Program (OSRP), which has recovered over 11,000 "excess, unwanted, abandoned and orphan radioactive sealed sources and other radioactive material from the environment."[12] The International Radiological Threat Reduction (IRTR) program has similar programs that work to secure radioactive sources around the globe. IRTR has secured over 200 sites with radioactive material, and has removed over 1,000 dangerous sources from Iraq.[13]

Representatives of 120 countries participated in the International Conference on Security of Radioactive Sources in Vienna on March 11-13, 2003. The conference recommended launching two international efforts under the aegis of the IAEA: the first, to facilitate the location, recovery, and securing of orphaned radioactive sources, and the second, to encourage and assist governments in their efforts to promote adequate radiation safety and security control infrastructures.[14] Both efforts are currently active under the auspices of the IAEA's Department of Nuclear Safety and Security. The conference also urged the IAEA to promote broad adherence to the Code of Conduct on the Safety and Security of Radioactive Sources, which was revised and released in 2004.[15]

The G8 Global Partnership Against the Spread of Weapons and Materials of Mass Destruction [See Issue Brief - Global Partnership] also acknowledged the threat of RDDs in 2003 by passing the Action Plan for Radioactive Source Security. The plan calls for guidance on export and import controls for high-risk radioactive sources, support for the IAEA's radiological source work, and assistance for the most vulnerable states.[16]

Not all recent developments have benefited radioactive source security. On July 29, 2005, Congress passed the Energy Policy Act of 2005, which relaxed restrictions on the export of highly enriched uranium (HEU) to be used in the production of medical isotopes. Not only can HEU be used to make a dirty bomb, it is also "the nuclear material of choice for terrorists, since HEU is the easiest material to use in manufacturing an improvised nuclear explosive device."[17] Increasing the amount of HEU globally, which in turn will increase the number of radioactive medical isotopes, provides terrorists with more material and sources for the development of dirty bombs, and seems to counteract other US programs aimed at securing dangerous radioactive sources.

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Obstacles

  • Materials for an RDD are widely available and often poorly secured. Although actions could be taken to secure the more dangerous radioactive materials, like many challenges, complete protection against RDD use cannot be guaranteed.
  • Similar to materials needed to produce chemical weapons, radioactive materials have a large number of commercial uses. There are 21,000 licenses to use radioactive materials in the United States alone. Consequently, actions to prevent proliferation and increase material security must be balanced against the need to ensure that industry can operate without unreasonable disruptions.
  • The Energy Policy Act of 2005 loosened the restrictions placed on highly enriched uranium exports from the US to be used in medical isotope production.

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Q & A

Q: What is a "dirty bomb" or radiological dispersal device (RDD)?
A: This is a device using a conventional (non-nuclear) explosive to scatter radioactive material to contaminate people in the vicinity or the environment in a larger area. RDDs do not rely on fission or fusion to create an explosion. [See Issue Brief - Nuclear Weapons]

Q: Why are RDDs believed to be attractive to terrorists?
A: The materials to build RDDs--conventional explosives and radioactive sources--are widely available. The explosives, or their ingredients, can be easily purchased. Radioactive sources are located in tens of thousands of facilities in the US and around the world where the level of security may not be adequate or where materials have been abandoned ("orphaned").

Q: What are the different categories of radioactive materials that are most likely to be found in dirty bombs?
A: The three types of nuclear materials most likely to be found in dirty bombs are alpha emitters, beta emitters, and gamma emitters. Alpha emitters, such as americium-241, decay by releasing a helium nucleus (two protons and two neutrons, called an alpha particle). Alpha emitters are relatively harmless unless they are ingested or inhaled or if they enter an open wound. Beta emitters, such as strontium-90, decay by releasing a high-energy electron (a beta particle). While Beta particles can cause the skin to burn, they are still relatively harmless unless internalized. Gamma emitters decay by releasing gamma rays, which consist of pure energy. Unlike alpha and beta particles, gamma rays easily penetrate the skin. In high doses they can cause Acute Radiation Syndrome (ARS).

Q: What is being done to deny terrorists access to the radioactive material they could use to build RDDs?
A: Organizations licensed to use radioactive sources in the US have been asked to increase the security of their facilities and materials; and in June 2002, the US, Russia, and the International Atomic Energy Agency (IAEA) established a working group that is developing a strategy to locate, secure, and recycle orphaned radiological sources throughout the states of the former Soviet Union. The US and the international community also have taken action, through the formation of The Global Initiative to Combat Nuclear Terrorism, which aims to secure all radioactive source material around the world. [See Issue Brief - Global Initiative]

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Quick Facts

  • There are millions of radioactive devices in the US alone; 21,000 licenses have been issued to permit the use of radioactive materials.[18]
  • Radioactive materials can be found in nearly every country around the world.
  • Detailed instructions for building RDDs were found in al Qaeda caves in Afghanistan.
  • Alpha and beta emitters from an RDD that are inhaled, swallowed, or exposed to an open wound can cause damage ranging from cancer to acute radiation syndrome (ARS), depending on the amount of the internalized radioactive material. Intense exposure to gamma rays, both internally and externally, can cause ARS. The type of radiation produced depends on the type of radioactive material.
  • RDDs can scatter radioactive materials that can chemically bind to concrete and asphalt or become lodged in crevices on the surfaces of buildings and streets.
  • RDDs could contaminate scores or even hundreds of blocks in an urban area, resulting in severe economic dislocations and many billions of dollars in decontamination, demolition, and reconstruction costs.
  • In 1987 in Brazil, thieves took a medical device containing a large amount of radioactive cesium from an abandoned cancer clinic. The material killed four people and gave eight people radiation sickness.
  • In January 2001, three woodcutters in the former Soviet Republic of Georgia found two cans of strontium-90 in the woods and were critically injured when they used them as a source of heat carried in their backpacks.

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Recent Legislation

  • The Dirty Bomb Prevention Act of 2005 (S. 1150 and H.R. 2689 in the 109th Congress, not enacted) would have enhanced restrictions on importing and exporting radioactive sources, established a mandatory source tracking system, and created a Task Force on Radiation Source Protection and Security.
  • Title II of the Nuclear Safety and Security Act of 2005 (S. 864, not enacted), as amended by the Senate Committee on Environment and Public Works, incorporated the proposed legislation of the Dirty Bomb Prevention Act.
  • The Energy Policy Act of 2005 (H.R. 6, which became Public Law 109-58) relaxed restrictions on the export of highly enriched uranium (HEU) for the production of medical isotopes. HEU can be used to make both RDDs and nuclear weapons.

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Applicable Treaties, Legislation, and Other International Agreements

  • The Atomic Energy Act of 1954 (42 USC §§2011-2259), the Energy Reorganization Act of 1974 (42 USC §§5801-79), and the Department of Energy Organization Act of 1977 (42 USC §§7101-7352) give primary responsibility for managing the control of nuclear energy and radioactive materials to the Nuclear Regulatory Commission (NRC) and the Department of Energy (DOE).
  • The Global Initiative to Combat Nuclear Terrorism aims to enhance nonproliferation cooperation and prevent nuclear materials from falling into the hands of terrorists. [See Issue Brief - Global Initiative]

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Talking Points

  • Because the materials and technology needed for production of a dirty bomb are relatively easy to acquire, an RDD is one of the most likely weapons of choice for terrorist organizations.
  • Although detonation of an RDD may not cause a massive number of casualties, the resulting radiological contamination could cause severe economic repercussions as well as strike a psychological blow to the population.
  • The US and the international community are in the beginning stages of the effort to protect against terrorist use of RDDs.
  • In June 2002, the US, Russia, and the International Atomic Energy Agency (IAEA) established a working group that is developing a strategy to locate, secure, and recycle orphaned radiological sources throughout the states of the former Soviet Union. However, such materials are available virtually worldwide, requiring broad-based international cooperation.
  • Even the best countermeasures will require a focus on the human element in ensuring the safe and secure handling of radioactive materials.

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Recommendations

  • A National Security Council designee should spearhead an interagency process to provide a detailed and timely reassessment of the global role of nonproliferation efforts in today's context, including those that have arisen in the past few years. This assessment should include provisions on how to secure radioactive sources from the threat of acquisition by non-state actors.
    [See Book Recommendation #1]
  • At the start of any program, the US agency involved should build consensus with the respective host country regarding threat perceptions. For example, Russia and the US differ in their threat perceptions of radiological dispersal devices and improvised nuclear devices, meaning their priorities for securing specific types of nuclear material differ as well.
    [See Book Recommendations #5 and #10]
  • Create a bicameral congressional task force whose objective is to regularly provide briefings from a broad array of the actors involved in actual implementation of nonproliferation initiatives. Greater Congressional understanding of the relevant issues and activities could lead to more effective programming for reducing the potential threat posed by RDDs. If a task force is politically infeasible, program directors at NNSA in charge of radiological threat reduction programs could brief Members of Congress.
    [See Book Recommendations #7 and #19]
  • The State Department should create an "information clearinghouse" for US Government-wide nonproliferation activities. The array of US Government and international non-and counter-proliferation programs necessitates a single gateway for information.
    [See Book Recommendation #22]

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Endnotes

[1] Anthony H. Cordesman, "Radiological Weapons as Means of Attack," Center for Strategic and International Studies, 8 November 2001, accessed at: http://www.csis.org/media/csis/pubs/radiological%5B1%5D.pdf.

[2] Michael Levi and Henry Kelly, "Weapons of Mass Disruption," Scientific American, 77, November 2002.

[3] Levi and Kelly, op. cit., note 2.

[4] International Atomic Energy Agency, "Q & A: Safety and Security of Radioactive Sources," Features: Radioactive Sources, accessed at: http://www.iaea.org/NewsCenter/Features/RadSources/radsrc_faq.html.

[5] Ibid.

[6] Henry Kelly, "Testimony before the Senate Committee on Foreign Relations," 6 March 2002, accessed at:

http://www.fas.org/ssp/docs/kelly_testimony_030602.pdf.

[7] Nuclear Regulatory Commission, "NRC: Backgrounder on Nuclear Security Enhancements Since Sept. 11, 2001," February 2005, accessed at: http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/security-enhancements.html.

[8] Nuclear Threat Initiative, "NIS Trafficking: Document Code 20020030," NIS Nuclear Trafficking, 2003, accessed at: http://www.nti.org/db/nistraff/2002/20020030.htm.

[9] Nuclear Threat Initiative, "NIS Trafficking: Document Code 20060060," NIS Nuclear Trafficking, February 2006, accessed at: http://www.nti.org/db/nistraff/2006/20060060.htm.

[10] Ibid.

[11] Rashid Alimov, "Radioisotope Thermoelectric Generators," Bellona, April 2005, accessed at: http://www.bellona.org/english_import_area/international/russia/navy/northern_fleet/incidents/37598.

[12] Los Alamos National Laboratory, "Off-Site Source Recovery Project," 2006, accessed at: http://osrp.lanl.gov/.

[13] Office of Defense Nuclear Nonproliferation, "International Radiological Threat Reduction Program," accessed at: http://www.nnsa.doe.gov/na-20/rtr.shtml.

[14] International Atomic Energy Agency, "Stronger Controls Needed to Prevent Terrorist 'Dirty Bombs,'" Press

Release, 13 March 2003, accessed at: http://www.iaea.org/NewsCenter/PressReleases/2003/prn200303.html.

[15] Ibid.

[16] Ministry of Foreign Affairs, France, "Nonproliferation of Weapons of Mass Destruction: Securing Radioactive Sources - A G8 Action Plan," Sommet D'Evian 2003, accessed at:
non_proliferation_of_weapons_of_mass_destruction_securing_radioactive_sources_-_a_g8_action_plan.html>.

[17] Scott Parrish, "Despite Nuclear Terrorism Risks, Congress Relaxes HEU Export Controls," Center for Nonproliferation Studies, 4 August 2005, accessed at: http://cns.miis.edu/pubs/week/050804.htm.

[18] Nuclear Regulatory Commission, "NRC: Backgrounder on Dirty Bombs" (April 2005), accessed at: http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/dirty-bombs-bg.html.

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Last Updated on May 31, 2007