Primitive forms of chemical warfare were used in ancient times to poison water supplies or to expose an enemy to noxious smoke. Chinese writings contain hundreds of recipes for the production of poisonous or irritating smokes for use in war. The poisoning of wells during the time of the Roman Empire has been documented. During World War I, Germany used chlorine gas against the Allied troops in Belgium in 1915. Five thousand troops died, and ten thousand became sick from the gas. Other chemical warfare attacks during that war included the use of phosgene and mustard gas.
Classes of modern chemical warfare agents include nerve agents, (Tabun, Sarin, Soman, and VX), blood agents (hydrogen cyanide and cyanogen chloride), choking agents and lung irritants (phosgene and chlorine gases), vesicants or blistering agents (mustard gas and Lewisite), as well as miscellaneous gases and sprays such as ammonia, Mace, pepper spray, and others.
Nerve agents are highly lethal. They cause convulsions, paralysis, and death by respiratory failure. They are similar to the organophosphate pesticides. Blood agents block the uptake of oxygen into the cells. They were used in extermination camps during World War II. They are suspected of having been used in the Middle East in the 1980s by both Syria and Iraq. More recently (2013), the use of Sarin is highly suspected in the reported use of chemical weapons in Syria.
Choking gases and lung irritants cause formation of water in the lungs, which interferes with the oxygen transport from the lungs to the bloodstream and ultimately leads to death. Vesicants or blistering agents cause severe blisters on the skin. They also affect the eyes and lungs. Death may occur from toxic shock within twenty-four hours of massive exposure.
The level of knowledge required for manufacturing chemical weapons is much less than that required for making biological ones. Many chemical warfare agents can be made by a chemistry graduate student. Most of the materials and equipment are relatively inexpensive and can be commercially purchased without notice or alarm. These agents are ideal weapons for terrorists. Two recent cases of chemical warfare/terrorism are described below.
In 1985, a religious cult in the Ozark Mountains of Arkansas obtained a thirty-gallon drum of potassium cyanide. Their plan was to poison the water supplies of New York, Chicago, and Washington DC. They believed they were on a divine mission and that these attacks, which were intended to punish heathens and unrepentant sinners, would hasten the return of the Messiah. However, the cult members lacked the scientific and medical background to fully execute an effective attack. The attempt did not materialize because prior to the planned attack, federal agents discovered the cyanide during a raid on the group’s compound.
In 1995, members of Aum Shinrikyo, a quasi-Buddist religious cult in Japan, released the nerve agent Sarin in the Tokyo subway system. The attack killed twelve people and injured more than a thousand. Several cult members, trained university scientists, produced the Sarin in a laboratory at its main compound at the base of Mount Fuji. They had planned to carry out several attacks with chemical and biological weapons in Tokyo and other Japanese cities. The attack would have been more deadly, but the perpetrators did not vaporize the Sarin. They carried plastic bags of the agent in liquid form onto subway cars and then punctured the bags, allowing the liquid to flow across the floors. The liquid evaporated slowly and only killed the passengers close to the release sites. Had they used a vaporizer, the death toll would have been much higher.
The same cult had used Sarin in a less publicized attack in Matsumoto in 1994. They attempted to kill three judges who were about to rule against them in a lawsuit. The attack killed seven people and injured144 others.
Chemical agents can be very effective as killing and disabling weapons both in the hands of terrorists and in all-out warfare. They are limited to localized or regional use when used as aerosolized agents. They can be used more widely as poisons in food or water supplies.
