The speaker on the Science Track panel “Chemical Warfare—An Introduction” (Saturday 4PM) Erica Borgers Klonkowski, a biochemist at the Naval Surface Warfare Center, took the audience on a whirlwind tour of the history, development, and modern use of chemical weapons. A chemical agent, she said, is a chemical compound used in tactical warfare. Some people consider anthrax a chemical weapon, but it is actually a biological one.
Chemical weapons may be incendiary and/or generate vapors that irritate or asphyxiate. Most have an odor, but the smell is not a warning. By the time the exposed person senses it, he or she is already affected. Although symptoms may take time to develop, there is no incubation period and chemical agents do not self-replicate.
Chemical agents reach victims in various ways, but three routes are common to all such weapons. They can be inhaled, absorbed through the skin—which need not be cut or damaged—by sinking through the pores, and ingested. When the chemical contaminates vegetation, people who eat those plants are exposed.
The four classes of chemical weapons are pulmonary or respiratory weapons, vesicants (blistering agents), asphyxiants (called “blood” agents), and nerve weapons. Civilian forces use lachrymators, which cause eyes to fill with tears without damaging them, and incapacitants.
Klonkowski noted that poisonous arrows and darts were used in prehistoric times, especially in the South Pacific. People there used snake venom and the secretions of jungle or rainforest amphibians against their foes. The first non-natural chemical weapons were used in the seventh century BCE by the Assyrians, who ignited pots of oil and hurled them at enemies.
A famous variant on this weapon was the Byzantines’ Greek fire, which they tried to spray on opposing ships. They kept the compound’s formula a closely guarded secret. In fact, Klonkowski said, they guarded the secret so closely that the formula died out when the area was conquered. No one has successfully replicated it, but scientists think it included resins, which caused it to stick to surfaces and made it volatile. Because the Byzantines were close to Black Sea oil deposits, petroleum may have been another ingredient, one that kept the substance on the water’s surface, posing a shipping hazard, as it burned. Naphtha, a volatile and explosive ingredient of napalm, may also have been part of the compound.
The Greeks deployed the first gaseous agents during the Peloponnesian War in the first century BCE. These compounds included sulfur which, when burned, vaporizes and gets into membranes and eyeballs. It combines with the water in those parts of the body and creates sulfuric acid, burning the membranes and soft tissues.
There were various experiments with different sorts of chemical agents over the next millennium or so, but such weapons took a giant leap forward during World War I, which saw the introduction of several types of poisonous gases. Sulfur mustard gas is one of the best known, but one of the most lethal was phosgene. It was often used with chloropicrin, which induced vomiting and forced soldiers to remove their gas masks, exposing them to phosgene or chlorine.
Now we’ve progressed to nerve gases such as Sarin, which was developed during an attempt to create a pesticide, and the V series, of which the best known is VX. Less than a drop of VX on the skin will kill a man of average weight in fifteen minutes, making VX the most toxic nerve agent ever synthesized.
The Organisation [[NOTE to editor & final reviewer—This is a European organization and so uses the European spelling with the S in the middle and not our American Z in its name]] for the Prohibition of Chemical Weapons (OPCW) was established in 1997. Located in the Netherlands at The Hague, it is the implementing body for the Chemical Weapons Convention, a treaty requiring all chemical weapon stockpiles to be destroyed by 2014 and prohibiting the further development, production, and retention of such weapons. Only eight NATO member nations are not signatories. The OPCW has the authority to conduct inspections to verify compliance with the convention.
Klonkowski noted that destroying stockpiles can be a difficult task. When one questioner asked if C4 explosive could do the job, she replied that using it would create further problems. Destruction requires particular neutralizing agents, which she was not at liberty to discuss. While the weapons are dangerous, she indicated, so are the neutralizing agents. No one wants an excess of either present.
