The Continuing Threat from Weapons
of Mass Destruction
Appendix B: Chemical Agents
March 27, 1996
Chemical warfare agents
are among the easiest WMD to produce. The toxicity of chemical agents falls
generally between that of the more deadly biological agents and that of
conventional weapons. The earliest chemical agents, first used in World War I,
were far less sophisticated and far less lethal than those developed in
subsequent decades. Proliferating nations have tended to first produce blister
agents and, as their technologies advance, to develop the more lethal nerve agents.
Types of CW Agents
- Choking agents are the
oldest CW agents. This class includes chlorine and phosgene, first used in
World War I. These agents have a corrosive effect on the respiratory
system that causes the lungs to fill with water and choke the victim.
These agents are delivered as heavy gases that remain near ground level
and tend to fill depressions. They dissipate rapidly in a breeze and are
among the least effective traditional CW agents.
- Blood agents are
absorbed into the body primarily by breathing; they prevent the normal
utilization of oxygen by the cells and cause rapid damage to body tissues.
This class includes cyanide and cyanogen chloride. They are highly
volatile and in a gaseous state dissipate rapidly in air. These agents are
most effective when delivered in a surprise attack.
- Blister agents are
used to cause medical casualties; they affect the eyes and lungs and
blister the skin. Such agents are simple to produce, and include sulfur
mustard, nitrogen mustard, and lewisite. Sulfur mustard is considered by
some as the ideal CW agent. It presents both a respiratory and a
percutaneous (skin) hazard, forcing personnel to wear masks and protective
clothing. It is persistent and presents a long-term hazard, forcing
decontamination of the battlefield.
- G-series nerve agents,
developed in the 1930s, cause paralysis of the respiratory musculature and
subsequent death, in sufficient concentration. They include tabun, sarin,
soman, and GF. These agents act rapidly and may be absorbed through the
skin or the respiratory tract. Some agents, such as tabun and sarin, tend
to be relatively nonpersistent, creating a short-term respiratory hazard
on the battlefield.
- V-series nerve agents,
developed in the 1950s, are similar to, but more advanced than, G-series
agents. This class includes VE, VG, VM, VS, and VX. These agents are more
toxic and more persistent than the G-agents and present a greater skin
hazard. They are used for long-term contamination of territory.
Production of CW Agents
Many CW agents, particularly choking, blood, and blister agents, are
relatively easy to produce. Some of their technologies are more than 80 years
old, making them accessible by virtually any Third World
country and many terrorist groups. Newer agents, particularly nerve agents, are
somewhat more difficult to produce. However, much of the technology to produce
these agents is widely available in the public domain and, as demonstrated by
the Aum Shinrikyo in Japan,
these agents can be produced by a determined terrorist group.
Production of CW agents is similar to that of legitimate commercial
compounds. Both involve use of standard chemical process equipment. Some of the
more sophisticated equipment is distinctive enough to warrant special
consideration, and some of this equipment is controlled by the Australia Group.
In particular, equipment that is exceptionally resistant to corrosion has
important applications for CW because of the highly corrosive compounds
encountered in CW agent production.
Methods of Delivery
Development of a dispersal device is somewhat more technologically complex
than the production of chemical agents. Many conventional munitions, such as
bombs, artillery shells, grenades, and mines, can be modified to deliver
chemical agents. A spray tank, commercially available for dissemination of
agricultural chemicals from aircraft, can be used to disseminate chemical
agents. Similarly, ground-based aerosol generators used to disseminate
pesticides can be used for CW purposes.
Chemical warfare (CW) can
be considered the military use of toxic substances such that the chemical
effects of these substances on exposed personnel result in incapacitation or
death. It is the impact of chemical effects instead of physical effects (such
as blast and heat) that distinguishes chemical weapons from conventional
weapons, even though both contain chemicals. In many cases in the Third World, there can be considerable confusion as to
what is a chemical weapon and what is not. Some countries consider smoke, flame,
incendiary, or riot control weapons to be chemical weapons and label them as
such. In addition, conventional weapons can inflict casualties resembling those
caused by chemical weapons.