NCPA - National Center for Policy Analysis

Airborne Biological Weapons

September 26, 2001

Fears that terrorists may have planned to use crop-dusting airplanes to spray U.S. cities with biological warfare agents need to be taken seriously, according to British experts. While such an attack would face technical difficulties, it could be extremely effective, they say.

According to Malcolm Dando, professor of international security at the University of Bradford, one of the best ways to distribute biological weapons is to use a crop dusting airplane.

Recently, Time magazine reported that the FBI found a manual on crop-dusting among the belongings of one of the suspects for the World Trade Center attacks.

The prospect of an anthrax attack was investigated in the 1990s by the U.S. Office of Technological Assessment. They concluded:

  • One hundred kilograms of virulent anthrax effectively dispersed at night over Washington D.C. could cause between one and three million deaths.
  • Crop-dusting airplanes can carry up to twice that capacity. Terrorists would first need to obtain and grow sufficient amounts of a virulent biological strain.
  • The most probable biological agent is anthrax spores.

Growing biological agents is a significant task in itself, says Dando. Processing the spores so they distribute efficiently, get inhaled and remain in peoples' lungs long enough to cause an infection would also take expertise, he says.

Dando says the likelihood of such an attack is low, although the attack on the World Trade Center towers has changed how the risk of different attacks is assessed.

Dando says that the best way to reduce the threat is to prevent the proliferation of expertise in manufacturing chemical and biological weapons.

Source: Ian Sample "Airborne biological weapon attacks are serious concern," New Scientist, September 24, 2001.


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