How Biological and Chemical Warfare Works

The Spread of Biological and Chemical Agents

The previous sections listed 11 of the most-feared chemical and biological agents. There are dozens of others that aren't as well known, either because they are not as toxic or not as easy to spread.

There are three ways to spread a chemical or biological agent so that it would infect a large number of people:


  • Through the air
  • Through a municipal water supply
  • Through the food supply

The most-feared scenario is through the air. Here are the techniques most commonly discussed:

  • A bomb or a missile explodes, spreading the chemical or biological agent over a wide area.
  • A crop-duster or other aircraft sprays the agent over a city.
  • A car or truck drives through the city spraying a fine mist along city streets in crowded areas.
  • Small bombs or aerosol canisters are released in crowded areas like subways, sports arenas or convention centers.

Here are some ways the U.S. is protecting civilians against attacks:

Chemical and biological weapons are huge, ever-changing subjects. To learn more about them, follow the links below.

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More Great Links


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