CHEMICAL   WARFARE

 

Chemical warfare (CW) involves using the toxic properties of chemical substances as weapons.

Chemical weapons have been used for millennia in the form of poisoned spears and arrows, but evidence can be found for the existence of more advanced forms of chemical weapons in ancient and classical times.

Ancient Greek myths about Hercules poisoning his arrows with the venom of the Hydra Monster are the earliest references to toxic weapons in western literature.

Homer's epics, the Iliad and the Odyssey, allude to poisoned arrows used by both sides in the legendary Trojan War (Bronze Age Greece).^[13]

Ancient Greek historians recount that Alexander the Great encountered poison arrows and fire incendiaries in India at Indus Basin in the 4th century BC.^[13]

The Imperial Japanese Army used mustard gas and the recently-developed blister agent Lewisite against Chinese troops and guerrillas. Experiments involving chemical weapons were conducted on live prisoners (Unit 731 and Unit 516). The Japanese also carried chemical weapons as they swept through Southeast Asia towards Australia.

Chemical warfare is different from the use of conventional weapons or nuclear weapons because the destructive effects of chemical weapons are not primarily due to any explosive force. The offensive use of living organisms (such as anthrax) is considered biological warfare rather than chemical warfare; however, the use of nonliving toxic products produced by living organisms (e.g. toxins such as botulinum toxin, ricin, and saxitoxin) is considered chemical warfare under the provisions of the Chemical Weapons Convention (CWC). Under this Convention, any toxic chemical, regardless of its origin, is considered a chemical weapon unless it is used for purposes that are not prohibited (an important legal definition known as the General Purpose Criterion).^[1]

Chlorine          Chloropicrin    Phosgene         Mustard gas    Lewisite         

G-series nerve agents             

V-series nerve agents  VE, VG, VM, VX  are collectively known as the "V-Series" class of nerve agents.

Toxic Ricin      Novichok nerve agents           sarin  nerve agents

VX nerve agent,          nerve agent soman      tabun, sarin, and soman

Possible targets include enemy flank positions, artillery regiments, commando posts or supply lines.

Classes

Chemical weapons are inert agents that come in four categories: choking, blister, blood and nerve.

Cyclosarin (GF)    Sarin (GB)             Soman (GD)         Tabun (GA)          VX        VR       Some insecticides

Novichok agents

Most Arsines       Cyanogen chloride

Hydrogen cyanide

Sulfur mustard (HD, H)                      Nitrogen mustard (HN-1, HN-2, HN-3)           Lewisite (L)

Phosgene oxime (CX)

• Chlorine             Hydrogen chloride           Nitrogen oxides               Phosgene
• Tear gas             Pepper spray                   Agent 15 (BZ)

Non-living biological proteins, such as:

• Ricin                 Abrin

Blood agents:

Cyanogen chloride: CK          Hydrogen cyanide: AC

Pulmonary agents:

Phosgene: CG

Lachrymatory agents:

Pepper spray: OC                    Tear gas: CN, CS, CR

Stockpiles of cylinders had to be stored at the front line, posing a great risk if hit by artillery shells. Gas delivery depended greatly on wind speed and direction. If the wind was fickle, as at Loos, the gas could blow back, causing friendly casualties.

Thermal dissemination is the use of explosives or pyrotechnics to deliver chemical agents. This technique, developed in the 1920s, was a major improvement over earlier dispersal techniques, in that it allowed significant quantities of an agent to be disseminated over a considerable distance. Thermal dissemination remains the principal method of disseminating chemical agents today.

Aerodynamic dissemination is the non-explosive delivery of a chemical agent from an aircraft, allowing aerodynamic stress to disseminate the agent. This technique is the most recent major development in chemical agent dissemination, originating in the mid-1960s.

Germany, the first side to employ chemical warfare on the battlefield, simply opened canisters of chlorine upwind of the opposing side and let the prevailing winds do the dissemination. Soon after, the French modified artillery munitions to contain phosgene – a much more effective method that became the principal means of delivery.

Chemical warfare agents

 

These agents may be in liquid, gas or solid form.

Liquid agents are generally designed to evaporate quickly; such liquids are said to be volatile or have a high vapor pressure. Many chemical agents are made volatile so they can be dispersed over a large region quickly.

Chemical warfare agents are divided into lethal and incapacitating categories. A substance is classified as incapacitating if less than 1/100 of the lethal dose causes incapacitation, e.g., through nausea or visual problems. The distinction between lethal and incapacitating substances is not fixed, but relies on a statistical average called the LD₅₀.

 

Persistency

One way to classify chemical warfare agents is according to their persistency, a measure of the length of time that a chemical agent remains effective after dissemination.

Agents classified as nonpersistent lose effectiveness after only a few minutes or hours or even only a few seconds.

 

Russia

Russia signed into the Chemical Weapons Convention on January 13, 1993 and ratified it on November 5, 1995. Declaring an arsenal of 39,967 tons of chemical weapons in 1997, by far the largest arsenal, consisting of blister agents: Lewisite, Sulfur mustard, Lewisite-mustard mix, and nerve agents: Sarin, Soman, and VX.