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Overview: Defense Against the Effects of Chemical and Biological Warfare Agents (From Medical Aspects of Chemical and Biological Warfare, P 1-7, 1997, Frederick R. Sidell, M.D., Ernest T. Takafuji, M.D., eds, et al., -- See NCJ-190599)

NCJ Number
Frederick R. Sidell M.D.; David R. Franz D.V.M
Date Published
7 pages

This document presents a review of chemical and biological events in the past 2 decades.


The most widespread and open use of chemical weapons on a battlefield in recent decades was by Iraq in its conflict with Iran. In contrast to reports of chemical use in earlier conflicts, this time the evidence of chemical use was conclusive. Chemical and biological agents differ in several important ways. Chemical agents are typically man-made through the use of industrial chemical processes. Biological agents are either replicating agents (bacteria or viruses) or nonreplicating materials (toxins or physiologically active proteins or peptides) that can be produced by living organisms. While many of the dermally active or volatile chemical agents can be disseminated as liquids or aerosols, the biological agents must be dispersed as respirable aerosols. In World War I, the use of chemical agents began with the small-scale use of irritants known today as riot control agents. In the period before World War II, German scientists synthesized the first nerve agents; during the war, Germany had thousands of tons of nerve agents stockpiled in munitions. Military chemical agents were classified as "persistent" and "nonpersistent." Persistent agents are those with low volatility or which evaporate slowly. Nonpersistent agents are those that are volatile and hence evaporate quickly. They are not expected to be present for more than several hours. Biological weapons can contain either replicating or nonreplicating agents. Unlike chemical warfare agents, all of the biological agents described cause syndromes that mimic or are identical to naturally occurring diseases. On the battlefield, knowledge of the chemical or biological agent threat and its medical and physical countermeasures can actually reduce the threat. The likelihood of such weapons causing panic among military personnel decreases when the leaders and troops become better educated regarding these agents. 5 references