Though an RDD would be designed to disperse radioactive material over a large area, a bomb that uses conventional explosives and produces a blast wave would be far more lethal to people than the hazard posed by radioactive material that may be mixed with the explosive. At levels created from probable sources, not enough radiation would be present to cause severe illness or death. A test explosion and subsequent calculations done by the United States Department of Energy found that assuming nothing is done to clean up the affected area and everyone stays in the affected area for one year, the radiation exposure would be "fairly high" but not fatal. Recent analysis of the nuclear fallout from the Chernobyl disaster confirms this, showing that the effect on many people in the surrounding area, although not those in proximity, was almost negligible.
Since a dirty bomb is unlikely to cause many deaths by radiation exposure, many do not consider this to be a weapon of mass destruction. Its purpose would presumably be to create psychological, not physical, harm through ignorance, mass panic, and terror. For this reason dirty bombs are sometimes called "weapons of mass disruption". Additionally, containment and decontamination of thousands of victims, as well as decontamination of the affected area might require considerable time and expense, rendering areas partly unusable and causing economic damage.
Dirty bombs and terrorism
Since the 9/11
attacks the fear of terrorist groups using dirty bombs has increased
immensely, which has been frequently reported in the media. The meaning of terrorism used here, is described by the U.S. Department of Defense's
definition, which is "the calculated use of unlawful violence or threat
of unlawful violence to inculcate fear; intended to coerce or to
intimidate governments or societies in the pursuit of goals that are
generally political, religious, or ideological objectives".
There have only ever been two cases of caesium-containing bombs, and neither was detonated. Both involved Chechnya. The first attempt of radiological terror was carried out in November 1995 by a group of Chechen separatists, who buried a caesium-137 source wrapped in explosives at the Izmaylovsky Park in Moscow. A Chechen rebel leader alerted the media, the bomb was never activated, and the incident amounted to a mere publicity stunt.
In December 1998, a second attempt was announced by the Chechen
Security Service, who discovered a container filled with radioactive
materials attached to an explosive mine. The bomb was hidden near a
railway line in the suburban area Argun, ten miles east of the Chechen capital of Grozny. The same Chechen separatist group was suspected to be involved.
Despite the increased fear of a dirty bombing attack, it is hard to
assess whether the actual risk of such an event has increased
significantly.
The following discussions on implications, effects and probability of
an attack, as well as indications of terror groups planning such, are
based mainly on statistics, qualified guessing and a few comparable scenarios.
Effect of a dirty bomb explosion
When dealing with the implications of a dirty bomb attack, there are two main areas to be addressed: (i) the civilian impact, not only dealing with immediate casualties and long term health issues, but also the psychological
effect and then (ii) the economic impact. With no prior event of a
dirty bomb detonation, it is considered difficult to predict the impact.
Several analyses have predicted that RDDs will neither sicken nor kill
many people.
Accidents with radioactives
The effects of uncontrolled radioactive contamination have been reported several times.
One example is the radiological accident occurring in Goiânia, Brazil, between September 1987 and March 1988: Two metal scavengers broke into an abandoned radiotherapy clinic and removed a teletherapy
source capsule containing powdered caesium-137 with an activity of 50
TBq. They brought it back to the home of one of the men to take it apart
and sell as scrap metal. Later that day both men were showing acute
signs of radiation illness with vomiting and one of the men had a swollen hand and diarrhea. A few days later one of the men punctured the 1 mm thick window of the capsule, allowing the caesium chloride
powder to leak out and when realizing the powder glowed blue in the
dark, brought it back home to his family and friends to show it off.
After 2 weeks of spread by contact contamination causing an increasing
number of adverse health effects, the correct diagnosis of acute radiation sickness
was made at a hospital and proper precautions could be put into
procedure. By this time 249 people were contaminated, 151 exhibited both
external and internal contamination of which 20 people were seriously
ill and 5 people died.
The Goiânia incident to some extent predicts the contamination
pattern if it is not immediately realized that the explosion spread
radioactive material, but also how fatal even very small amounts of
ingested radioactive powder can be. This raises worries of terrorists using powdered alpha emitting material, that if ingested can pose a serious health risk, as in the case of deceased former K.G.B. spy Alexander Litvinenko, who either ate, drank or inhaled polonium-210. "Smoky bombs" based on alpha emitters might easily be just as dangerous as beta or gamma emitting dirty bombs.
Public perception of risks
For
the majority involved in an RDD incident, the radiation health risks
(i.e. increased probability of developing cancer later in life due to
radiation exposure) are comparatively small, comparable to the health
risk from smoking five packages of cigarettes on a daily basis. The fear of radiation
is not always logical. Although the exposure might be minimal, many
people find radiation exposure especially frightening because it is
something they cannot see or feel, and it therefore becomes an unknown
source of danger. Dealing with public fear may prove the greatest
challenge in case of an RDD event.
Policy, science and media may inform the public about the real danger
and thus reduce the possible psychological and economic effects.
Statements from the U.S. government after 9/11 may have contributed unnecessarily to the public fear of a dirty bomb. When United States Attorney General John Ashcroft on June 10, 2002, announced the arrest of José Padilla, allegedly plotting to detonate such a weapon, he said:
[A] radioactive "dirty bomb" (...) spreads radioactive material that is highly toxic to humans and can cause mass death and injury.
— Attorney General John Ashcroft
This public fear of radiation also plays a big role in why the costs
of an RDD impact on a major metropolitan area (such as lower Manhattan)
might be equal to or even larger than that of the 9/11 attacks. Assuming the radiation levels are not too high and the area does not need to be abandoned such as the town of Pripyat near the Chernobyl reactor,
an expensive and time consuming cleanup procedure will begin. This will
mainly consist of tearing down highly contaminated buildings, digging
up contaminated soil and quickly applying sticky substances to remaining
surfaces so that radioactive particles adhere before radioactivity
penetrates the building materials. These procedures are the current state of the art for radioactive contamination
cleanup, but some experts say that a complete cleanup of external
surfaces in an urban area to current decontamination limits may not be
technically feasible.
Loss of working hours will be vast during cleanup, but even after the
radiation levels reduce to an acceptable level, there might be residual
public fear of the site including possible unwillingness to conduct
business as usual in the area. Tourist traffic is likely never to resume.
There is also a psychological warfare
element to radioactive substances. Visceral fear is not widely aroused
by the daily emissions from coal burning, for example, even though a National Academy of Sciences study found this causes 10,000 premature deaths a year in the US population of 317,413,000. Medical errors leading to death in U.S. hospitals are estimated to be between 44,000 and 98,000. It is "only nuclear radiation that bears a huge psychological burden — for it carries a unique historical legacy".
Constructing and obtaining material for a dirty bomb
In
order for a terrorist organization to construct and detonate a dirty
bomb, it must acquire radioactive material. Possible RDD material could
come from the millions of radioactive sources used worldwide in the
industry, for medical purposes and in academic applications mainly for
research. Of these sources, only nine reactor produced isotopes stand out as being suitable for radiological terror: americium-241, californium-252, caesium-137, cobalt-60, iridium-192, plutonium-238, polonium-210, radium-226 and strontium-90, and even from these it is possible that radium-226 and polonium-210 do not pose a significant threat. Of these sources the U.S. Nuclear Regulatory Commission has estimated that within the U.S., approximately one source is lost, abandoned or stolen every day of the year. Within the European Union the annual estimate is 70.
There exist thousands of such "orphan" sources scattered throughout the
world, but of those reported lost, no more than an estimated 20 percent
can be classified as a potential high security concern if used in a
RDD. Especially Russia is believed to house thousands of orphan sources, which were lost following the collapse of the Soviet Union.
A large but unknown number of these sources probably belong to the high
security risk category. Noteworthy are the beta emitting strontium-90
sources used as radioisotope thermoelectric generators for beacons in lighthouses in remote areas of Russia. In December 2001, three Georgian
woodcutters stumbled over such a power generator and dragged it back to
their camp site to use it as a heat source. Within hours they suffered
from acute radiation sickness and sought hospital treatment. The International Atomic Energy Agency (IAEA) later stated that it contained approximately 40 kilocuries (1.5 PBq) of strontium, equivalent to the amount of radioactivity released immediately after the Chernobyl accident (though the total radioactivity release from Chernobyl was 2500 times greater at around 100 MCi (3,700 PBq)).
Although a terrorist organization might obtain radioactive material through the "black market",
and there has been a steady increase in illicit trafficking of
radioactive sources from 1996 to 2004, these recorded trafficking
incidents mainly refer to rediscovered orphan sources without any sign
of criminal activity, and it has been argued that there is no conclusive evidence for such a market.
In addition to the hurdles of obtaining usable radioactive material,
there are several conflicting requirements regarding the properties of
the material the terrorists need to take into consideration: First, the
source should be "sufficiently" radioactive to create direct
radiological damage at the explosion or at least to perform societal
damage or disruption. Second, the source should be transportable with
enough shielding to protect the carrier, but not so much that it will be
too heavy to maneuver. Third, the source should be sufficiently
dispersible to effectively contaminate the area around the explosion.
An example of a worst-case scenario is a terror organization
possessing a source of very highly radioactive material, e.g. a
strontium-90 thermal generator, with the ability to create an incident
comparable to the Chernobyl accident. Although the detonation of a dirty
bomb using such a source might seem terrifying, it would be hard to
assemble the bomb and transport it without severe radiation damage and
possible death of the perpetrators involved. Shielding the source
effectively would make it almost impossible to transport and a lot less
effective if detonated.
Due to the three constraints of making a dirty bomb, RDDs might
still be defined as "high-tech" weapons and this is probably why they
have not been used up to now.
Possibility of terrorist groups using dirty bombs
The present assessment of the possibility of terrorists using a dirty bomb is based on cases involving ISIS.
This is because the attempts by this group to acquire a dirty bomb
coming to light in all forms of media, in part due to the attention this
group received for their involvement in the London bridge attack.
On 8 May 2002, José Padilla
(a.k.a. Abdulla al-Muhajir) was arrested on suspicion that he was an
Al-Qaeda terrorist planning to detonate a dirty bomb in the U.S. This
suspicion was raised by information obtained from an arrested top
Al-Qaeda official in U.S. custody, Abu Zubaydah,
who under interrogation revealed that the organization was close to
constructing a dirty bomb. Although Padilla had not obtained radioactive
material or explosives at the time of arrest, law enforcement
authorities uncovered evidence that he was on reconnaissance for usable
radioactive material and possible locations for detonation.
It has been doubted whether José Padilla was preparing such an attack,
and it has been claimed that the arrest was highly politically
motivated, given the pre-9/11 security lapses by the CIA and FBI.
Later, these charges against José Padilla were dropped. Although
there was no hard evidence for Al-Qaeda possessing a dirty bomb, there
is a broad agreement that Al-Qaeda poses a potential dirty bomb attack
threat because they need to overcome the alleged image that the U.S. and its allies are winning the war against terror.
A further concern is the argument, that "if suicide bombers are
prepared to die flying airplanes into building, it is also conceivable
that they are prepared to forfeit their lives building dirty bombs".
If this would be the case, both the cost and complexity of any
protective systems needed to allow the perpetrator to survive long
enough to both build the bomb and carry out the attack, would be
significantly reduced.
Several other captives were alleged to have played a role in this plot.
Guantanamo captive Binyam Mohammed has alleged he was subjected to extraordinary rendition, and that his confession of a role in the plot was coerced through torture.
He sought access through the American and United Kingdom legal systems to provide evidence he was tortured.
Guantanamo military commission
prosecutors continue to maintain the plot was real, and charged Binyam
for his alleged role in 2008. However they dropped this charge in
October 2008, but maintain they could prove the charge and were only
dropping the charge to expedite proceedings.
US District Court Judge Emmet G. Sullivan insisted that the administration still had to hand over the evidence that justified the dirty bomb charge, and admonished United States Department of Justice
lawyers that dropping the charge "raises serious questions in this
court's mind about whether those allegations were ever true."
In 2006, Dhiren Barot from North London pleaded guilty of conspiring to murder innocent people within the United Kingdom and United States using a radioactive dirty bomb. He planned to target underground car parks within the UK and buildings in the U.S. such as the International Monetary Fund, World Bank buildings in Washington D.C., the New York Stock Exchange, Citigroup buildings and the Prudential Financial buildings in Newark, New Jersey. He also faces 12 other charges including, conspiracy to commit public nuisance,
seven charges of making a record of information for terrorist purposes
and four charges of possessing a record of information for terrorist
purposes. Experts say if the plot to use the dirty bomb was carried out
"it would have been unlikely to cause deaths, but was designed to affect
about 500 people."
In January 2009, a leaked FBI report described the results of a search of the Maine home of James G. Cummings, a white supremacist
who had been shot and killed by his wife. Investigators found four
one-gallon containers of 35 percent hydrogen peroxide, uranium, thorium,
lithium metal, aluminum powder, beryllium,
boron, black iron oxide and magnesium as well as literature on how to
build dirty bombs and information about cesium-137, strontium-90 and
cobalt-60, radioactive materials. Officials confirmed the veracity of the report but stated that the public was never at risk.
In April 2009, the Security Service of Ukraine announced the arrest of a legislator and two businessmen from the Ternopil Oblast. Seized in the undercover sting operation was 3.7 kilograms of what was claimed by the suspects during the sale as plutonium-239, used mostly in nuclear reactors and nuclear weapons, but was determined by experts to be probably americium, a "widely used" radioactive material which is commonly used in amounts of less than 1 milligram in smoke detectors, but can also be used in a dirty bomb. The suspects reportedly wanted US$ 10 million for the material, which the Security Service determined was produced in Russia during the era of the Soviet Union and smuggled into Ukraine through a neighboring country.
In July 2014, ISIS militants seized 88 pounds (40 kg) of uranium compounds from Mosul University.
The material was unenriched and so could not be used to build a
conventional fission bomb, but a dirty bomb is a theoretical
possibility. However, uranium's relatively low radioactivity makes it a
poor candidate for use in a dirty bomb.
Little is known about civil preparedness to respond to a dirty bomb attack. The Boston Marathon appeared to many to be a situation with high potential for use of a dirty bomb as a terrorist weapon. However, the bombing attack that occurred on April 15, 2013
did not involve use of dirty bombs. Any radiological testing or
inspections that may have occurred following the attack were either
conducted sub rosa or not at all. Also, there was no official dirty bomb "all clear" issued by the Obama administration. Massachusetts General Hospital
had, apparently under their own disaster plan, issued instructions to
their emergency room to be prepared for incoming radiation poisoning
cases.
Terrorist organizations may also capitalize on the fear of radiation
to create weapons of mass disruption rather than weapons of mass
destruction. A fearful public response may in itself accomplish the
goals of a terrorist organization to gain publicity or destabilize
society.
Even simply stealing radioactive materials may trigger a panic reaction
from the general public. Similarly, a small-scale release of
radioactive materials or a threat of such a release may be considered
sufficient for a terror attack.
Particular concern is directed towards the medical sector and
healthcare sites which are "intrinsically more vulnerable than
conventional licensed nuclear sites".
Opportunistic attacks may range to even kidnapping patients whose
treatment involve radioactive materials. Of note is the public reaction
to the Goiânia accident,
in which over 100,000 people admitted themselves to monitoring, while
only 49 were admitted to hospitals. Other benefits to a terrorist
organization of a dirty bomb include economic disruption in the area
affected, abandonment of affected assets (such a buildings, subways) due
to public concern, and international publicity useful for recruitment.
Dirty bomb tests
Israel
carried out a four-year series of tests on nuclear explosives to
measure the effects were “hostile forces” ever to use them against
Israel, Israel’s Haaretz daily newspaper reported June 8, 2015.
Detection and prevention
Dirty bombs may be prevented by detecting illicit radioactive materials in shipping with tools such as a Radiation Portal Monitor. Similarly, unshielded radioactive materials may be detected at checkpoints by Geiger Counters, gamma-ray detectors, and even Customs and Border Patrol (CBS) pager-sized radiation detectors.
Hidden materials may also be detected by x-ray inspection and heat
emitted may be picked up by infrared detectors. Such devices, however,
may be circumvented by simply transporting materials across unguarded
stretches of coastline or other barren border areas.
One proposed method for detecting shielded Dirty Bombs is Nanosecond Neutron Analysis (NNA).
Designed originally for the detection of explosives and hazardous
chemicals, NNA is also applicable to fissile materials. NNA determines
what chemicals are present in an investigated device by analyzing
emitted γ-emission neutrons and α-particles created from a reaction in
the neutron generator. The system records the temporal and spatial
displacement of the neutrons and α-particles within separate 3D regions.
A prototype dirty-bomb detection device created with NNA is
demonstrated to be able to detect uranium from behind a 5 cm-thick lead
wall.
Other radioactive material detectors include Radiation Assessment and
Identification (RAID) and Sensor for Measurement and Analysis of
Radiation Transients, both developed by Sandia National Laboratories.
The International Atomic Energy Agency
(IAEA) recommends certain devices be used in tandem at country borders
to prevent transfer of radioactive materials, and thus the building of
dirty bombs.
They define the four main goals of radiation detection instruments as
detection, verification, assessment and localization, and identification
as a means to escalate a potential radiological situation. The IAEA
also defines the following types of instruments:
- Pocket-Type Instruments: these instruments provide a low-power, mobile option to detection that allows for security officers to passively scan an area for radioactive materials. These devices should be easily worn, should have an alarm threshold of three times normal radiation levels, and should have a long battery life - over 800 hours.
- Handheld Instruments: these instruments may be used to detect all types of radiation (including neutron) and may be used to search specific targets flexibly. These instruments should aim for ease of use and speed, ideally weighing less than 2 kg and being able to make measurements in less than a second.
- Fixed, installed instruments: these instruments provide a continuous, automatic detection system that can monitor pedestrians and vehicles that pass through. To work effectively pedestrians and vehicles should be led close to the detectors, as performance is directly related to range.
Legislative and regulatory actions can also be used to prevent access
to materials needed to create a dirty bomb. Examples include the 2006
U.S. Dirty Bomb Bill, the Yucca Flats proposal, and the Nunn-Lungar act.
Similarly, close monitoring and restrictions of radioactive materials
may provide security for materials in vulnerable private-sector
applications, most notably in the medical sector where such materials
are used for treatments. Suggestions for increased security include isolation of materials in remote locations and strict limitation of access.
One way to mitigate a major effect of a radiological weapons may
also be to educate the public on the nature of radioactive materials. As
one of the major concerns of a dirty bomb is the public panic proper
education may prove a viable counter-measure. Education on radiation is considered by some to be "the most neglected issue related to radiological terrorism".
Personal safety
The Dirty Bomb Fact Sheet from FEMA states that the main danger
of a dirty bomb comes from the initial blast rather than the radioactive
materials. To mitigate the risk of radiation exposure, however, FEMA suggests the following guidelines:
- Covering the mouth/nose with cloth to reduce risk of breathing in radioactive materials.
- Avoiding touching materials touched by the explosion.
- Quickly relocating inside to shield from radiation.
- Remove and pack up clothes. Keep clothes until instructed by authorities how to dispose of them.
- Keep radioactive dust outside.
- Remove all dust possible by showering with soap and water.
- Avoid taking potassium iodide, as it only prevents effects from radioactive iodine and may instead cause a dangerous reaction.
Other uses of the term
The term has also been used historically to refer to certain types of nuclear weapons. Due to the inefficiency of early nuclear weapons, only a small amount of the nuclear material would be consumed during the explosion. Little Boy had an efficiency of only 1.4%. Fat Man, which used a different design and a different fissile material, had an efficiency of 14%. Thus, they tended to disperse large amounts of unused fissile material, and the fission products, which are on average much more dangerous, in the form of nuclear fallout.
During the 1950s, there was considerable debate over whether "clean"
bombs could be produced and these were often contrasted with "dirty"
bombs. "Clean" bombs were often a stated goal and scientists and
administrators said that high-efficiency nuclear weapon design could create explosions which generated almost all of their energy in the form of nuclear fusion, which does not create harmful fission products.
But the Castle Bravo accident of 1954, in which a thermonuclear weapon
produced a large amount of fallout which was dispersed among human
populations, suggested that this was not what was actually being used in
modern thermonuclear weapons, which derive around half of their yield
from a final fission stage of the fast fissioning of the uranium tamper
of the secondary. While some proposed producing "clean" weapons, other
theorists noted that one could make a nuclear weapon intentionally
"dirty" by "salting" it with a material, which would generate large
amounts of long-lasting fallout when irradiated by the weapon core. These are known as salted bombs; a specific subtype often noted is a cobalt bomb.
In popular culture
- In the 1964 British movie Goldfinger, both Auric Goldfinger and James Bond refer to the nuclear device being smuggled into Fort Knox as "dirty."
- The crime drama television series Numb3rs has an episode that revolves around a dirty bomb (season 1, episode 10).
- In a two-part 2011 episode of Castle, former US soldiers plot to detonate a dirty bomb in New York City and frame a Syrian immigrant for the crime.
- In the 2012 series finale of Flashpoint, an officer is poisoned by caesium from a dirty bomb and is administered Prussian blue to assist in recovery.
- In the 2013 Indian movie Vishwaroopam, the plot revolves around a dirty bomb developed by scraping caesium from oncological equipment to trigger a blast in New York City.
- In the 2014 movie, Batman: Assault on Arkham, the Joker has a dirty bomb which he plans on detonating in Gotham.
- In the January 14, 2016 Republican presidential debates, Ben Carson referenced dirty bombs twice when speaking on US foreign policy.
- In the June 1, 2015 game by Splash Damage, Dirty Bomb, the game is played in a dirty bomb fallout area in London.
- In the Madam Secretary episode "Right of the Boom", a dirty bomb is detonated at a women's education conference in Washington, D.C.
- The American political drama web television series House of Cards has an episode that revolves around a dirty bomb (season 5, episode 7).
- In the 2006 movie Right At Your Door multiple dirty bombs are detonated in Los Angeles.
- In the 2018 video game Detroit: Become Human one of the endings has a character setting off a dirty bomb in southern Detroit.
- In the 2019 video game Metro Exodus one of Russia's major cities, Novosibirsk, has been struck by a dirty bomb during the end of World War III.
