Academic journal article Defense Horizons

Dirty Bombs: The Threat Revisited

Academic journal article Defense Horizons

Dirty Bombs: The Threat Revisited

Article excerpt


Nuclear radiation, invisible and detectable only with special instruments, has the power to terrify--in part because of its association with nuclear weapons--and to become an instrument of terrorists. Radioactive isotopes can be spread widely with or without high explosives by a radiological dispersion device (RDD) or so-called dirty bomb. This paper provides a general overview of the nature of RDDs and sources of material for them and estimates the effects of an assault, including casualties and economic consequences. Many experts believe that an RDD is an economic weapon capable of inflicting devastating damage on the United States. This paper is in full agreement with that assessment and makes some quantitative estimates of the magnitude of economic disruption that can be produced by various levels of attack. It is also generally believed that even a very large RDD is unlikely to cause many human casualties, either immediately or over the long term. A careful examination of the consequences of the tragic accident in Goiania, Brazil, however, shows that some forms of radiological attack could kill tens or hundreds of people and sicken hundreds or thousands. Nevertheless, contrary to popular belief, RDDs are not weapons of mass destruction.

The authors recommend several policies and actions to reduce the threat of RDD attack and increase the ability of the Federal Government to cope with the consequences of one. With improved public awareness and ability to respond, it should be possible to strip RDDs of their power to terrorize.

Many Americans first heard the term dirty bomb on June 10, 2002, when Attorney General John Ashcroft announced the arrest of Jose Padilla on the charge of plotting to detonate a device containing both high explosive and very radioactive material. In that announcement the attorney general used the following definition: "[A] radioactive 'dirty bomb' involves exploding a conventional bomb that not only kills victims in the immediate vicinity, but also spreads radioactive material that is highly toxic to humans and can cause mass death and injury."

On March 6 of the same year, the Senate Foreign Relations Committee held a hearing on the question of radiological dispersion devices (RDDs), the technical term for dirty bombs, and their ability to cause casualties and damage. At that hearing, experts from inside and outside government testified that, while an RDD could cause economic harm, it was unlikely to cause deaths or injuries beyond the area immediately destroyed by the high explosives used to spread the radioactive material.

Proper preparation for an incident of radiological terror requires an understanding of the real effects of an RDD attack, yet these two views of the effects are in direct conflict.

In the intervening months an intermediate possibility has emerged: prompt (roughly from one day to one month) deaths or acute radiation sickness from the radioactive material scattered by the RDD may be few in number, although a large (but as yet unpredictable) number of Americans could suffer quite high exposures if they ingest or inhale any of the particles. The authors propose that planning for an RDD attack be based on this assessment.

Radiation and Radioactivity

Three different kinds of radiation are emitted from radioactive materials: [alpha] rays, which are helium nuclei; [beta] rays, which are electrons; and [gamma] rays, which are very high energy, short wave length light.

[alpha] particles stop in a few inches of air, or a thin sheet of cloth or even paper. [alpha]-emitting isotopes pose serious health dangers if inhaled.

[beta] particles are also easily stopped in, for example, aluminum foil or human skin. Unless they are ingested or inhaled, [beta]-emitters pose little danger to people, although direct contact with a strong [beta] source can cause deep and serious beta burns on skin. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed


An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.