Though not nearly as powerful as a nuclear weapon, a so-called dirty bomb, a type of Radiological Dispersal Device (RDD), may yield fear and panic, contaminate property, and offer a powerful psychological weapon. It is often used as an area of denial device against civilian populations that may spread radioactive material within a range of a few hundred yards to several miles of the explosion site. Though one has never been detonated, the radioactive contaminants of a dirty bomb are speculated to be far less than that of a nuclear explosion. The use of dirty bomb may nonetheless be considered an act of terror for its ability to produce mass panic.
What Is A Dirty Bomb?
A dirty bomb is, in theory, a conventional weapon that has been augmented with a radiological substance. The delivery method could be a missile, an airplane stocked with radioactive materials, or a strategically planted improvised explosive device. Although such a device has never been used, there have been reports of terrorists seeking RDDs, and governments have tried to prepare for the potential terrorist use of such devices.
A small-scale conventional explosive, such as backpack bomb, would not inflict widespread destruction. Much of the radioactive material will burn upon ignition, meaning that health effects may also be marginal. However, the psychological effects could be monumental if a dirty bomb were to go off in a heavily populated area, creating unsubstantiated mass panic about radioactive fallout.
What Are Radiological Materials?
Radiological materials go through a process of radioactive decay, which makes exposure to them potentially harmful and radioactive. Fissile materials — or those that can sustain an explosive fission chain reaction — present the largest threat. These materials include Plutonium-239 (PU-239), Uranium-235 (U-235), and Uranium-233 (U-233) — all of which are sourced for fission and fusion nuclear weapons.
Many radiological materials used for legitimate commercial uses may be instrumentalized for a dirty bomb. For instance, Americium-241, Cesium-137, and Cobalt-60 are all used in gauges for the gas and oil industries. Strontium-90 has medical applications in radiotherapy. Iridium-192, recently a source of concern in Mexico and Iraq following thefts and misplacements, is used in gauges for welding and in certain cancer treatments. Any of these isotopes could be a component in a dirty bomb.
What Is Being Done?
Theft and loss of radiological material present substantial threats that are augmented by human negligence and poor physical security regimes. To overcome these challenges, the international community has prioritized tracking incidents of theft, establishing best practices for protecting the materials, and securing or removing materials from vulnerable locations.
Tracking/Reporting: The International Atomic Energy Agency’s (IAEA) Incident and Trafficking Database was developed to keep track of any and all international cases of theft or loss of material around the world, of which there were a total of 3,686 confirmed incidents between 1993-2019. The US Nuclear Regulatory Commission (NRC) also creates public incident reports on radiological mishaps.
Building Consensus: Four Nuclear Security Summits were held from 2010-2016 and have produced greater coordination and emphasis on the importance of securing nuclear and radiological material. The final summit in 2016 concluded with the announcement that an amendment to the the decades-old Convention on the Physical Protection of Nuclear Material (CPPNM) will enter into force, setting standards for adequate fissile materials security and holding countries accountable for failing to meet those standards.
Securing and Removing Materials: As part of their commitments under the summits, countries pledged to secure their most dangerous radioactive sources. The United States is also partnering with businesses, hospitals, and government organizations in more than 85 countries to assist in securing these dangerous materials. However, momentum has slowed and a group of nuclear security experts has urged the Biden administration to quickly restore U.S. leadership in strengthening global nuclear security and lists priorities.
Sources: IAEA, Nuclear Regulatory Commission, Nuclear Threat Initiative, White House