Ypres 1915

When Chemicals First Became an Effective Weapon of War

Francis Deblauwe

April 22, 2003

April 22, 1915 saw the first tactical use of gas as a weapon of war in modern history. French and Algerian troops were the main victims when the German troops in World War I released chlorine gas at the front line near the village of Steenstrate in Belgium. After setting up 520 gas cylinders, the Germans had waited for a month for just the right northeasterly wind before releasing a thick green-yellow gas cloud (168 tons). Right from the start, chemical weapons were meant to incapacitate the enemy physically as much as psychologically. The defenders fled in disarray and the advancing Germans, with cotton wadding tied over their faces, encountered at first only dying and wounded stragglers. Chlorine attacks the eyes and mucous membranes while contact with the skin can cause severe burns. As we all know from trips to the municipal swimming pool, it emits a strong odor even at doses far below harm. On the battlefield, it caused suffocation, constriction of the chest, tightness in the throat, and edema of the lungs. As little as 2.5 mg/l in the atmosphere is enough to bring on death in minutes. It is estimated 5,000 soldiers died a gruesome death and a further 15,000 were severely injured.

In an all too common irony of war, the German High Command was somewhat surprised by the scale of the devastation. They were unable fully to take advantage of the 4.5 miles-wide breach the attack created. Due also to the month-long wait, there were not enough backup German troops available to support the advance all the way to Ypres. This attack did start the so-called Second Ypres battle, named after the major stronghold of the Allies in Northwest Belgium the Germans would never capture. The Allies or “Triple Entente” of France, Britain and Russia were opposed by the Central Powers or “Triple Alliance” of the German, Austro-Hungarian and Ottoman Empires. The key to the aforementioned stronghold was the Ypres Salient: a bulge in the western front line centered on a cluster of small hills just outside Ypres (Dutch: Ieper) proper, protruding to such an extent that the enemy could shoot right across it. In other words, the unenviable defenders got shot at from three sides. Actually, in August 1914, the French were the first to test gas on the World War I battlefield, i.e., xylyl bromide (tear gas), followed by a German attempt in October with a sneezing agent. Both instances went by almost unnoticed. The Germans then proceeded with another test on the Russian front at Bolimov in January. This time, the enemy did not suffer any real effects because the cold temperature prevented the vaporization of the xylyl bromide used.

April 23, 1914, the nearby Canadian troops at the Ypres Salient, who had been witnesses to the first attack, suffered many thousands of casualties in a second gas attack at the hamlet of St. Juliaan but were able to hold their positions anyway by covering their faces with handkerchiefs drenched in urine. Two more unsuccessful gas attacks in April were followed by the German gas-aided capture of the strategic Hill 60 on May 5 from the British. Gas became a mainstay of the German assaults on the Ypres Salient from here on, even though Germany's initial tactical advantage proved ephemeral. On the Allied side there was great indignation about the use of this inhumane and “unfair” weapon, sneaking up on you without giving a soldier a fighting chance. Sure, grenades and other more concrete lethal threats also came out of nowhere, enemy unseen, but this was different, an escalation. Nevertheless, the British too had been researching chemical weapons even before the war started. The Allies had the advantage that the prevailing wind around Ypres is southwesterly, blowing toward the Germans. Phosgene was first deployed by the British in December. It caused temporary blindness and greatly inflamed the nose and throat. Severe lung injury led to death with several-hours delayed action. This chemical was usually combined with chlorine to help eject it better from containers; the British called this weapon White Star. Phosgene was far more lethal than any other common-use gas weapon: 85% of Western Front soldiers killed as the result of chemical attack were killed by phosgene.

The German chemical industry (e.g., Bayer, Badische Anilin), however, was more advanced and maintained its qualitative lead. Through the remainder of World War I, new invisible and odorless gasses were deployed as well as gasses with delayed effect. In July 1917, the notorious mustard gas first saw the battlefield. It is also known as yperite after its main theater of deployment. It was almost odorless and took 12 hours to take effect. Only small amounts had to be added to high-explosive shells to be effective, stuck to the ground and, once in the soil, remained active for several weeks. Many a wounded soldier died a horrible death in the no-man's land between the opposing trenches after getting trapped in a bomb crater filled with mustard gas. This particular gas resulted in skin blisters, very sore eyes, vomiting, internal and external bleeding and it attacked the bronchial tubes. For the terminal cases, it could take 4 to 5 weeks till death finally set in. About 80% of allied gas attack casualties were the result of mustard gas exposure. A British field nurse wrote:

“We have heaps of gassed cases at present : there are 10 in this ward alone. I wish those people who write so glibly about this being a holy war, and the orators who talk so much about going on no matter how long the war lasts and what it may mean, could see a case - to say nothing of 10 cases of mustard gas in its early stages - could see the poor things all burnt and blistered all over with great suppurating blisters, with blind eyes - sometimes temporally, sometimes permanently - all sticky and stuck together, and always fighting for breath, their voices a whisper, saying their throats are closing and they know they are going to choke.”

Vera Brittain, Testament of Youth, 1933

Even though tearing gases were primarily meant only to incapacitate soldiers, some of them could still be lethal if suffered in high enough concentrations, e.g., bromacetone. The favorite tearing gas was xylyl bromide because it was relatively cheap to produce. Blood-agent-type gases attacked the blood stream in a soldier's body and literally suffocated him. Most common were cyanide gases which usually came in cocktails, e.g., the French vincennite compound was made up of 50% hydrogen cyanide, 30% arsenic trichloride, 15% stannic chloride and 5% chloroform. This particular poison gas dissipated too fast in the wind and proved to be rather inefficient however.

In the last year of the war about 25% of the artillery shells contained gas. It is estimated that 15% of the World War I battlefield dead were gas weapon victims, compared with about 50% from artillery fire. From the initial wet handkerchiefs the military switched quickly to primitive gas masks. The British developed a fully effective model by 1917. Then it was on to protective clothing against mustard gas that penetrated though the skin. These continuously-enhanced precautionary measures usually enabled 90% of the soldiers to return to their trenches. Of course, standards were not very high: as long as you could move your arms and legs, you were deemed fit to shoot and run at the enemy. Many soldiers were suffering aftereffects both physical and psychological, increasing further the already ghastly casualty figures caused by the conventional weapons, e.g., the Battle of Passchendaele (a.k.a. Third Ypres, Fall 1917) saw at least 244,000 British (incl. Canadian and Australian) and 200,000 German casualties. Scores of World War I veterans suffered from breathing problems for the rest of their life.

In 1918, a German corporal named Adolf Hitler was temporarily blinded by a British gas attack in Flanders. Maybe his own experience with the grueling pain inflicted by gas weapons may have played a role in not deploying it as a tactical weapon on the battlefields of the World War II. All sides in this war built and maintained huge stockpiles of chemical weapons but they were not really utilized on the battlefield except by Japan in China. On the other hand, gasses were put to horribly efficient use in the Nazi concentration camps. Apart from an experiment with carbon monoxide, the Nazis generally used hydrogen cyanide in its commercial form “Zyklon-B.” Ever since, chemical weapons use has been mostly small scale and sporadic. The notable exception has been Iraq which has used all kinds of chemical weapons against its Kurds and against Iran throughout the 1980s. A recurring problem through the years has been the issue of verification. Warring parties are eager to accuse the other side of chemical-weapons use but definite proof is usually hard to come by. Ideally, impartial inspectors should be allowed to visit the scene immediately and take samples. As you can understand, this is hardly ever possible. Nevertheless, the 1993 Chemical Weapons Convention offers the hope that this scourge can be eradicated from our planet. The ancillary Organization for the Prohibition of Chemical Weapons has been doing a laborious but steady job of steering and supervising the process of eliminating the nebulous stockpiles of mass poison.

APPENDICES

I. Most common chemical weapons used at the Western front in World War I

II. Typology of chemical weapons

III. Use of chemicals as weapons after World War I

IV. International treaties and conventions with relevance to chemical weapons

I. Most common chemical weapons used at the Western front in World War I

Use indicated for the 3 main armies only. Belgium bought chemical ammunition from Britain and France while the US used British ones. Army-specific names of chemical weapons are given in parentheses behind the country information.

1. Blistering agents

- Carbonyl chloride or phosgene or phosgene oxime, used by Britain (CG, CX), France (collongite) and Germany; also a choking agent; killed most soldiers (up to 85% of dead from chemical attack)

- Dichloroethyl sulfide or mustard gas or sulfur mustard or distilled mustard, used by Britain (HS, H, HD, BB, Y3, Y4), France (yperite) and Germany (Lost); responsible for most Allied gas casualties (80%)

- Ethyl dichloroarsine or ED, used by Germany (Dick); also a choking and sneezing/vomiting agent

- Phenyl dichloroarsine or PD or PDA or MA, used by Germany

2. Blood agents

- Bromobenzyl cyanide, used by France (camite) and Germany

- Cyanogen bromide, used by France (campilite) and Germany (E-Stoff)

- Cyanogen chloride, used by France (mauguinite)

- Hydrogen cyanide or hydrocyanic acid or or prussic acid or AC, used by France (forestite, main component of vincennite compound)

3. Choking agents

- Carbonyl chloride or phosgene or phosgene oxime, used by Britain (CG), France (collongite) and Germany; also a blistering agent

- Chlorine, used by France (bertholite) and Germany (Chlor)

- Diphenyl cyanoarsine, used by Britain (DC, CDA) and Germany (Clark II); also a sneezing/vomiting agent

- Ethyl dichloroarsine or ED, used by Germany (Dick); also a blistering and sneezing/vomiting agent

4. Nerve agents

None

5. Sneezing/vomiting agents

- Dianisidine chlorosulfonate, used by Germany

- Diphenyl chloroarsine, used by Britain (DA) and Germany (Clark I)

- Diphenyl cyanoarsine, used by Britain (DC, CDA) and Germany (Clark II); also a choking agent

- Ethyl dichloroarsine or ED, used by Germany (Dick); also a blistering and choking agent

6. Tearing agents

- Benzyl bromide or lachrymogene, used by France (cyclite) and Germany (T-Stoff)

- Bromoacetone, used by Britain (BA) and Germany (B-Stoff)

- (Mono)bromomethyl ethyl ketone, used by France (homomartonite) and Germany (Bn-Stoff)

- (Mono)chloromethyl chloroformate, used by France (palite) and Germany

- Chloropicrin, used by Britain (PS), France (aquinite) and Germany (Klop)

- Dibromomethyl ethyl ketone, used by Germany

- Dichloromethyl ether, used by France (cici)

- Ethyl iodoacetate, used by Britain (SK)

- Xylyl bromide, used by France and Germany (T-Stoff); first one used

II. Typology of chemical weapons

A lot of the so-called gases are not gases but liquids or solids in colloidal suspension (aerosols).

1. Blistering agents (vesicants)

- Mode of action: absorption through lungs, skin

- Burns skin, mucous membranes and eyes; causes large blisters on exposed skin

- Blisters windpipe and lungs

- Large number of casualties, low % of deaths

- Dispersal: liquid, aerosol and vapor

- Example: mustard gas

2. Blood agents (toxics)

- Mode of action: absorption through lungs

- Destroys ability of tissues to utilize oxygen, causing them to "starve" and strangling the heart

- Dispersal: gas

- Example: hydrogen cyanide

3. Choking agents (asphyxiants, asphyxiators, suffocants)

- Mode of action: absorption through lungs

- Fluid builds up in lungs, choking victim

- Dispersal: gas

- Example: chlorine

4. Nerve agents

- Mode of action: absorption through lungs, skin

- Causes seizures, loss of body control

- Paralyses muscles, including heart and diaphragm

- Lethal doses can cause death in 5 minutes

- Dispersal: liquid, vapor and aerosol

- Example: sarin

5. Sneezing/vomiting agents (sternutators)

- Mode of action: absorption through lungs

- Causes bronchial irritation

- Produces headaches, nausea and vomiting

- No lasting ill effects

- Dispersal: very fine dust

- Example: diphenyl chloroarsine

6. Tearing agents (lachrymators)

- Mode of action: absorption through eyes

- Causes eye irritation, temporary blindness

- No lasting ill effects unless very high doses when they can become choking agents

- Dispersal:

- Example: bromoacetone

III. Use of chemicals as weapons after World War I

- 1919, by Britain, in the Russian civil war

- 1919, maybe by Britain, in Afghanistan

- 1920s, by Chinese warlords, in China

only scattered use if at all

- 1925, by Spain, in Morocco

- early 1930s, by the Soviet Union, against the Basmachi in Central Asia

- 1930, by Italy, in Libya

mustard gas

- 1936, by Italy, in Ethiopia

tear gas, mustard gas

- 1930s, in conflict between Kuomintang and insurgents in Manchuria (China)

- 1937-1945, by Japan, in China during World War II

mustard gas, lewisite (chlorovinyl dichloroarsine), chloropicrin, diphenyl cyanoarsine, hydrogen cyanide, phosgene, diphenyl chloroarsine and chloroacetophenone; Japan tried to destroy and bury these ammunitions at the end of the war and large amounts are still unaccounted for; Japan is only recently semi-officially admitting it used them

- 1939, by Poland, against invading Germany

isolated incident

- 1939-1945, by Germany, during World War II

a few erroneous or accidental uses in Poland and the Crimea

- 1960s-1975, by the US, in Vietnam, Laos and Cambodia

not strictly anti-personnel "Agent Orange," a defoliant containing dioxin with multi-year delayed effect; CS (O-chlorobenzylmalonitrile) and DM (adamsite) gases

- 1963-1967, by Egypt, in the North Yemeni civil war

mustard gas, probably phosgene

- 1975, maybe by Cambodia, in Cambodia

"Yellow Rain" (trichothecene mycotoxins); against insurgents

- 1975, maybe by Laos, in Laos

"Yellow Rain" (trichothecene mycotoxins); against Hmong

- 1980-1988, by Iraq, Iran-Iraq War

mustard gas, tabun, sarin, VX (methylphosphonothioic acid ), maybe chlorine, lewisite, nitrogen mustard

- 1979-1981, maybe by Soviet Union, in Afghanistan

"Yellow Rain" (trichothecene mycotoxins)

- 1988, maybe by Libya, in Chad

mustard gas

- 1985, by Vietnam, in Cambodia

hydrogen cyanide, phosgene

- 1987-1988, by Iraq, against the Kurds

mustard gas, tabun, sarin. maybe hydrogen cyanide

- 1995 and 1997, maybe Sudan, in Civil War

mustard gas

IV. International treaties and conventions with relevance to chemical weapons

- 1874 Brussels Convention on the Law and Customs of War

Prohibits the employment of poison or poisoned arms

- 1899 Hague Declaration IV, 2 Concerning Asphyxiating Gases

Prohibits the use of projectiles for the diffusion of asphyxiating or deleterious gases

- 1922 Washington Treaty Relating to the Use of Submarines and Noxious Gases in Warfare

Never entered into force

- 1923 Convention on the Limitation of Armaments of Central American States

Only regional; prohibits gas warfare

- 1925 Geneva Protocol for the Prohibition of Use in War of Asphyxiating, Poisonous or Other Gases, and of Bacteriological Methods of Warfare

Prohibits the use in war of poisonous, as well as asphyxiating or other gases, and of all analogous liquids, materials or devices, along with the use of bacteriological methods of warfare; entered into force on February 8, 1928; basically a no-first-use treaty; ratified by the US only in 1975

- 1972 Biological and Toxin Weapons Convention (BTWC)

In full, Convention on the Prohibition of the Development, Production and Stockpiling of Bacteriological and Toxin Weapons and on Their Destruction; entered into force in 1975; toxins "whatever their origin"

- 1993 Chemical Weapons Convention (CWC)

In full, Convention on the Prohibition of Development, Production, Stockpiling, and Use of Chemical Weapons and on Their Destruction; entered into force in 1997; the Organisation for the Prohibition of Chemical Weapons (OPCW) in The Hague is responsible for the implementation; Palau acceded as 175th country on February 3, 2003; countries assume responsibility for stockpiles left abroad