Common Chemical Agent Threats

Randall R. Mccafferty, M.D., Peter J. Lennarson, M.D.


Neurosurg Focus. 2002;12(3) 

In This Article

Abstract and Introduction

The events of September 11, 2001, highlight the fact that we live in precarious times. National and global awareness of the resolve and capabilities of terrorists has increased. The possibility that the civilian neurosurgeon may confront a scenario involving the use of chemical warfare agents has heightened. The information reported in this paper serves as a primer on the recognition, decontamination, and treatment of trauma patients exposed to chemical warfare agents.

Prior to World War I, chemical agents were considered but were infrequently used or ineffective products of warfare. The Chinese used arsenical smokes as early as 1000 B.C. The Spartans used noxious smokes during the Peloponnesian War. During the American Civil War, numerous proposals for the use of chlorine, sulfur, chloroform, and hydrochloric and sulfuric acids were developed; however, most proposals were likely never acted upon.

With the onset of World War I, few people believed that the proposals and research into chemical weapons would result in any significant battlefield operations. Initial attempts at chemical warfare were ineffective against opposition forces. In April and May of 1915, German forces successfully deployed large stores of chlorine gas by wind drift against Allied forces defending Ypres. Within the next 2 years, the chemical warfare techniques practiced by German and Allied forces evolved into the use of phosgene gas, cyanogens, and vesicants. In addition, both forces were supplied with chemical protective devices, including gas masks. By Armistice Day in 1918, 26 million casualties were recorded, approximately 1 million of which were attributable to gas warfare.

In the years between World War I and World War II, new chemical weapons and protective and deployment capabilities were developed. All of the major nations involved in World War I and several other countries developed chemical weapons programs. Participants involved in international conferences and treaties attempted to define, limit, and/or prohibit the storage, development, and training in the use and deployment of chemicals in warfare.

At the start of World War II, training in the use, storage, and deployment of, and protection from chemical warfare was high. Although there was no major event involving the use of chemical agents during World War II, the capabilities of participating countries were impressive. In addition to choking, blister, and blood agents, nerve agents were being produced in mass quantities. Despite significant efforts by all parties to garner intelligence on the capabilities of opposition forces, the magnitude of chemical weapons programs was not fully understood until after the war.

Throughout the remainder of the 20th century, chemical weaponry continued to be developed and used in major wars around the world. Those involved in international organizations and treaties continued to define and restrict various aspects of chemical weapons programs as well as in the more recently developing atomic and biological programs. As recently as the Persian Gulf War, the alleged use of nerve and mustard agents by Iraqi troops has been reported. Following that war, there have been reports of chemical agent use ordered by Saddam Hussein against Kurd and Shiite Muslims as well as proliferation of chemical weapons development in Libya.

Finally in 1993, the long awaited Chemical Weapons Convention was finalized. This treaty prohibited the development, production, stockpiling, and use of chemical weapons and provided for the verification and destruction of known stockpiles. Although 130 countries signed the treaty, notable exceptions included Iraq and North Korea.[3] Despite diplomatic efforts, chemical weapons will remain a threat in warfare and more recently have become a potential weapon of the terrorist. In 1994, a religious cult, Aum Shinrikyo, released nerve gas in a residential area in Matsumoto, Japan, and in 1995 a sarin attack occurred in a Tokyo subway.

The ease with which chemical weapons can be obtained and manufactured increases the concern that nonmilitary people may be exposed to chemical agents. These agents are most effectively employed against individuals who lack knowledge of their properties as well as to protect against themselves and personnel against them. Cities, ports, and airfields are especially vulnerable civilian targets. Following terrorist activity against the Pentagon and World Trade Center on September 11, 2001, President Bush established a Homeland Defense program in the US.

In light of these recent events, there is a real possibility that civilian medical personnel may be exposed to patients and circumstances involving chemical weapons. The following is a brief synopsis of those chemicals and their effects that a neurosurgeon may need to recognize and be able to treat when managing victims in a mass-casualty scenario. Chemical weapons may be classified in a variety of different ways. For this discussion, the common nerve agents, vesicants, blood agents, choking agents, and riot control agents will be discussed. In addition, basic protective mechanisms and decontamination procedures will be addressed.


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