Chemical weapons in World War I - wikipedia Chemical weapons in World War I British troops blinded by poison gas during the Battle of Estaires, 1918 The use of toxic chemicals as weapons dates back thousands of years, but the first large scale use of chemical weapons was during World War I. They were primarily used to demoralize, injure, and kill entrenched defenders, against whom the indiscriminate and generally very slow - moving or static nature of gas clouds would be most effective. The types of weapons employed ranged from disabling chemicals, such as tear gas, to lethal agents like phosgene, chlorine, and mustard gas. This chemical warfare was a major component of the first global war and first total war of the 20th century. The killing capacity of gas was limited, with about ninety thousand fatalities from a total of 1.3 million casualties caused by gas attacks. Gas was unlike most other weapons of the period because it was possible to develop countermeasures, such as gas masks. In the later stages of the war, as the use of gas increased, its overall effectiveness diminished. The widespread use of these agents of chemical warfare, and wartime advances in the composition of high explosives, gave rise to an occasionally expressed view of World War I as `` the chemist 's war '' and also the era where weapons of mass destruction were created. The use of poison gas by all major belligerents throughout World War I constituted war crimes as its use violated the 1899 Hague Declaration Concerning Asphyxiating Gases and the 1907 Hague Convention on Land Warfare, which prohibited the use of `` poison or poisoned weapons '' in warfare. Contents 1 History of poison gas in World War I 1.1 1914 : Tear gas 1.2 1915 : Large - scale use and lethal gases 1.2. 1 Effectiveness and countermeasures 1.2. 2 British gas attacks 1.3 1915 : More deadly gases 1.4 1916 : Austrian use 1.5 1917 : Mustard gas 1.6 Post-war 1.6. 1 Effect on World War II 2 Casualties 2.1 British casualties 2.2 Civilian casualties 3 Countermeasures 4 Delivery systems 5 Unexploded weapons 6 Gases used 7 Long - term health effects 8 Notes 9 References 10 Further reading 11 External links History of poison gas in World War I See also : Weapons of World War I 1914 : tear gas The earliest military uses of chemicals during World War I were tear - inducing irritants rather than fatal or disabling poisons. During World War I, the French army was the first to employ gas, using 26 mm grenades filled with tear gas ( ethyl bromoacetate ) in August 1914. The small quantities of gas delivered, roughly 19 cm3 per cartridge, were not even detected by the Germans. The stocks were rapidly consumed and by November a new order was placed by the French military. As bromine was scarce among the Entente allies, the active ingredient was changed to chloroacetone. In October 1914, German troops fired fragmentation shells filled with a chemical irritant against British positions at Neuve Chapelle ; the concentration achieved was so small that it too was barely noticed. None of the combatants considered the use of tear gas to be in conflict with the Hague Treaty of 1899, which prohibited the launching of projectiles containing asphyxiating or poisonous gas. 1915 : large - scale use and lethal gases The first instance of large - scale use of gas as a weapon was on 31 January 1915, when Germany fired 18,000 artillery shells containing liquid xylyl bromide tear gas on Russian positions on the Rawka River, west of Warsaw during the Battle of Bolimov. Instead of vaporizing, the chemical froze and failed to have the desired effect. The first killing agent used by the German military was chlorine. Chlorine is a powerful irritant that can inflict damage to the eyes, nose, throat and lungs. At high concentrations and prolonged exposure it can cause death by asphyxiation. German chemical companies BASF, Hoechst and Bayer ( which formed the IG Farben conglomerate in 1925 ) had been making chlorine as a by - product of their dye manufacturing. In cooperation with Fritz Haber of the Kaiser Wilhelm Institute for Chemistry in Berlin, they began developing methods of discharging chlorine gas against enemy trenches. According to the fieldpost letter of Major Karl von Zingler, the first chlorine gas attack by German forces took place before 2 January 1915 : `` In other war theatres it does not go better and it has been said that our Chlorine is very effective. 140 English officers have been killed. This is a horrible weapon... ''. By 22 April 1915, the German Army had 168 tons of chlorine deployed in 5,730 cylinders from Langemark -- Poelkapelle, north of Ypres. At 17 : 30, in a slight easterly breeze, the gas was released, forming a grey - green cloud that drifted across positions held by French Colonial troops from Martinique, as well as the 1st Tirailleurs and the 2nd Zouaves from Algeria. Faced with an unfamiliar threat these troops broke ranks, abandoning their trenches and creating an 8,000 - yard ( 7 km ) gap in the Allied line. The German infantry were also wary of the gas and, lacking reinforcements, failed to exploit the break before the 1st Canadian Division and assorted French troops reformed the line in scattered, hastily prepared positions 1,000 -- 3,000 yards ( 910 -- 2,740 m ) apart. The Entente governments claimed the attack was a flagrant violation of international law but Germany argued that the Hague treaty had only banned chemical shells, rather than the use of gas projectors. In what became the Second Battle of Ypres, the Germans used gas on three more occasions ; on 24 April against the 1st Canadian Division, on 2 May near Mouse Trap Farm and on 5 May against the British at Hill 60. The British Official History stated that at Hill 60, `` 90 men died from gas poisoning in the trenches or before they could be got to a dressing station ; of the 207 brought to the nearest dressing stations, 46 died almost immediately and 12 after long suffering. '' On 6 August, German troops used chlorine gas against Russian troops defending the Fortress of Osowiec. Surviving defenders drove back the attack and retained the fortress. Germany used chemical weapons on the eastern front in an attack at Rawka, south of Warsaw. The Russian army took 9,000 casualties, with more than 1,000 fatalities. In response, the artillery branch of the Russian army organised a commission to study the delivery of poison gas in shells. Effectiveness and countermeasures British emplacement after German gas attack ( probably phosgene ) It quickly became evident that the men who stayed in their places suffered less than those who ran away, as any movement worsened the effects of the gas, and that those who stood up on the fire step suffered less -- indeed they often escaped any serious effects -- than those who lay down or sat at the bottom of a trench. Men who stood on the parapet suffered least, as the gas was denser near the ground. The worst sufferers were the wounded lying on the ground, or on stretchers, and the men who moved back with the cloud. Chlorine was less effective as a weapon than the Germans had hoped, particularly as soon as simple countermeasures were introduced. The gas produced a visible greenish cloud and strong odour, making it easy to detect. It was water - soluble, so the simple expedient of covering the mouth and nose with a damp cloth was effective at reducing the effect of the gas. It was thought to be even more effective to use urine rather than water, as it was known at the time that chlorine reacted with urea ( present in urine ) to form dichloro urea. Chlorine required a concentration of 1,000 parts per million to be fatal, destroying tissue in the lungs, likely through the formation of hydrochloric acid when dissolved in the water in the lungs ( 2Cl + 2H O → 4HCl + O ). Despite its limitations, chlorine was an effective psychological weapon -- the sight of an oncoming cloud of the gas was a continual source of dread for the infantry. Countermeasures were quickly introduced in response to the use of chlorine. The Germans issued their troops with small gauze pads filled with cotton waste, and bottles of a bicarbonate solution with which to dampen the pads. Immediately following the use of chlorine gas by the Germans, instructions were sent to British and French troops to hold wet handkerchiefs or cloths over their mouths. Simple pad respirators similar to those issued to German troops were soon proposed by Lieutenant - Colonel N.C. Ferguson, the A.D.M.S. of the 28th Division. These pads were intended to be used damp, preferably dipped into a solution of bicarbonate kept in buckets for that purpose ; other liquids were also used. Because such pads could not be expected to arrive at the front for several days, army divisions set about making them for themselves. Locally available muslin, flannel and gauze were used, officers were sent to Paris to buy more and local French women were employed making up rudimentary pads with string ties. Other units used lint bandages manufactured in the convent at Poperinge. Pad respirators were sent up with rations to British troops in the line as early as the evening of 24 April. In Britain the Daily Mail newspaper encouraged women to manufacture cotton pads, and within one month a variety of pad respirators were available to British and French troops, along with motoring goggles to protect the eyes. The response was enormous and a million gas masks were produced in a day. The Mail 's design was useless when dry and caused suffocation when wet -- the respirator was responsible for the deaths of scores of men. By 6 July 1915, the entire British army was equipped with the more effective `` smoke helmet '' designed by Major Cluny MacPherson, Newfoundland Regiment, which was a flannel bag with a celluloid window, which entirely covered the head. The race was then on between the introduction of new and more effective poison gases and the production of effective countermeasures, which marked gas warfare until the armistice in November 1918. British gas attacks British infantry advancing through gas at Loos, 25 September 1915 Football team of British soldiers with gas masks, Western front, 1916 A British gas bomb from 1915 The British expressed outrage at Germany 's use of poison gas at Ypres and responded by developing their own gas warfare capability. The commander of II Corps, Lieutenant General Sir Charles Ferguson, said of gas : It is a cowardly form of warfare which does not commend itself to me or other English soldiers... We can not win this war unless we kill or incapacitate more of our enemies than they do of us, and if this can only be done by our copying the enemy in his choice of weapons, we must not refuse to do so. The first use of gas by the British was at the Battle of Loos, 25 September 1915, but the attempt was a disaster. Chlorine, codenamed Red Star, was the agent to be used ( 140 tons arrayed in 5,100 cylinders ), and the attack was dependent on a favourable wind. On this occasion the wind proved fickle, and the gas either lingered in no man 's land or, in places, blew back on the British trenches. This was compounded when the gas could not be released from all the British canisters because the wrong turning keys were sent with them. Subsequent retaliatory German shelling hit some of those unused full cylinders, releasing gas among the British troops. Exacerbating the situation were the primitive flannel gas masks distributed to the British. The masks got hot, and the small eye - pieces misted over, reducing visibility. Some of the troops lifted the masks to get fresh air, causing them to be gassed. 1915 : more deadly gases Plate I, Microscopic section of human lung from phosgene shell poisoning, American Red Cross and Medical Research Committee, An Atlas of Gas Poisoning, 1918 The deficiencies of chlorine were overcome with the introduction of phosgene, which was prepared by a group of French chemists led by Victor Grignard and first used by France in 1915. Colourless and having an odour likened to `` mouldy hay, '' phosgene was difficult to detect, making it a more effective weapon. Phosgene was sometimes used on its own, but was more often used mixed with an equal volume of chlorine, with the chlorine helping to spread the denser phosgene. The Allies called this combination White Star after the marking painted on shells containing the mixture. Phosgene was a potent killing agent, deadlier than chlorine. It had a potential drawback in that some of the symptoms of exposure took 24 hours or more to manifest. This meant that the victims were initially still capable of putting up a fight ; this could also mean that apparently fit troops would be incapacitated by the effects of the gas on the following day. In the first combined chlorine -- phosgene attack by Germany, against British troops at Wieltje near Ypres, Belgium on 19 December 1915, 88 tons of the gas were released from cylinders causing 1069 casualties and 69 deaths. The British P gas helmet, issued at the time, was impregnated with sodium phenolate and partially effective against phosgene. The modified PH Gas Helmet, which was impregnated with phenate hexamine and hexamethylene tetramine ( urotropine ) to improve the protection against phosgene, was issued in January 1916. Around 36,600 tons of phosgene were manufactured during the war, out of a total of 190,000 tons for all chemical weapons, making it second only to chlorine ( 93,800 tons ) in the quantity manufactured : Germany 18,100 tons France 15,700 tons United Kingdom 1,400 tons ( also used French stocks ) United States 1,400 tons ( also used French stocks ) Phosgene was never as notorious in public consciousness as mustard gas, but it killed far more people, about 85 % of the 100,000 deaths caused by chemical weapons during World War I. 1916 : Austrian use Italian dead after the Austrian gas attack on Monte San Michele On 29 June 1916, Austrian forces attacked the Italian lines on Monte San Michele with a mix of phosgene and chlorine gas. Thousands of Italian soldiers died in this first chemical weapons attack on the Italian Front. 1917 : mustard gas Plate X, Microscopic section of human lung from mustard gas poisoning, American Red Cross and Medical Research Committee, An Atlas of Gas Poisoning, 1918 The most widely reported and, perhaps, the most effective chemical agent of the First World War was sulfur mustard, known as `` mustard gas ''. It is a volatile oily liquid. It was introduced as a vesicant by Germany in July 1917 prior to the Third Battle of Ypres. The Germans marked their shells yellow for mustard gas and green for chlorine and phosgene ; hence they called the new gas Yellow Cross. It was known to the British as HS ( Hun Stuff ), and the French called it Yperite ( named after Ypres ). A Canadian soldier with mustard gas burns, 1917 / 1918 Mustard gas is not an effective killing agent ( though in high enough doses it is fatal ) but can be used to harass and disable the enemy and pollute the battlefield. Delivered in artillery shells, mustard gas was heavier than air, and it settled to the ground as an oily liquid. Once in the soil, mustard gas remained active for several days, weeks, or even months, depending on the weather conditions. The skin of victims of mustard gas blistered, their eyes became very sore and they began to vomit. Mustard gas caused internal and external bleeding and attacked the bronchial tubes, stripping off the mucous membrane. This was extremely painful. Fatally injured victims sometimes took four or five weeks to die of mustard gas exposure. One nurse, Vera Brittain, wrote : `` I wish those people who talk about going on with this war whatever it costs could see the soldiers suffering from mustard gas poisoning. Great mustard - coloured blisters, blind eyes, all sticky and stuck together, always fighting for breath, with voices a mere whisper, saying that their throats are closing and they know they will choke. '' The polluting nature of mustard gas meant that it was not always suitable for supporting an attack as the assaulting infantry would be exposed to the gas when they advanced. When Germany launched Operation Michael on 21 March 1918, they saturated the Flesquières salient with mustard gas instead of attacking it directly, believing that the harassing effect of the gas, coupled with threats to the salient 's flanks, would make the British position untenable. Gas never reproduced the dramatic success of 22 April 1915 ; it became a standard weapon which, combined with conventional artillery, was used to support most attacks in the later stages of the war. Gas was employed primarily on the Western Front -- the static, confined trench system was ideal for achieving an effective concentration. Germany also used gas against Russia on the Eastern Front, where the lack of effective countermeasures resulted in deaths of over 56,000 Russians, while Britain experimented with gas in Palestine during the Second Battle of Gaza. Russia began manufacturing chlorine gas in 1916, with phosgene being produced later in the year. Most of the manufactured gas was never used. The British Army first used mustard gas in November 1917 at Cambrai, after their armies had captured a stockpile of German mustard gas shells. It took the British more than a year to develop their own mustard gas weapon, with production of the chemicals centred on Avonmouth Docks. ( The only option available to the British was the Despretz -- Niemann -- Guthrie process ). This was used first in September 1918 during the breaking of the Hindenburg Line with the Hundred Days ' Offensive. The Allies mounted more gas attacks than the Germans in 1917 and 1918 because of a marked increase in production of gas from the Allied nations. Germany was unable to keep up with this pace despite creating various new gases for use in battle, mostly as a result of very costly methods of production. Entry into the war by the United States allowed the Allies to increase mustard gas production far more than Germany. Also the prevailing wind on the Western Front was blowing from west to east, which meant the British more frequently had favourable conditions for a gas release than did the Germans. When the United States entered the war, it was already mobilizing resources from academic, industry and military sectors for research and development into poison gas. A Subcommittee on Noxious Gases was created by the National Research Committee, a major research centre was established at Camp American University, and the 1st Gas Regiment was recruited. The 1st Gas Regiment eventually served in France, where it used phosgene gas in several attacks. The Artillery used mustard gas with significant effect during the Meuse Argonne Offensive on at least three occasions. The United States began large - scale production of an improved vesicant gas known as Lewisite, for use in an offensive planned for early 1919. By the time of the armistice on 11 November, a plant near Willoughby, Ohio was producing 10 tons per day of the substance, for a total of about 150 tons. It is uncertain what effect this new chemical would have had on the battlefield, as it degrades in moist conditions. Post-war By the end of the war, chemical weapons had lost much of their effectiveness against well trained and equipped troops. At that time, chemical weapon agents inflicted an estimated 1.3 million casualties. Nevertheless, in the following years, chemical weapons were used in several, mainly colonial, wars where one side had an advantage in equipment over the other. The British used poison gas, possibly adamsite, against Russian revolutionary troops beginning on 27 August 1919 and contemplated using chemical weapons against Iraqi insurgents in the 1920s ; Bolshevik troops used poison gas to suppress the Tambov Rebellion in 1920, Spain used chemical weapons in Morocco against Rif tribesmen throughout the 1920s and Italy used mustard gas in Libya in 1930 and again during its invasion of Ethiopia in 1936. In 1925, a Chinese warlord, Zhang Zuolin, contracted a German company to build him a mustard gas plant in Shenyang, which was completed in 1927. Public opinion had by then turned against the use of such weapons which led to the Geneva Protocol, an updated and extensive prohibition of poison weapons. The Protocol, which was signed by most First World War combatants in 1925, bans the use ( but not the stockpiling ) of lethal gas and bacteriological weapons. Most countries that signed ratified it within around five years ; a few took much longer -- Brazil, Japan, Uruguay, and the United States did not do so until the 1970s, and Nicaragua ratified it in 1990. The signatory nations agreed not to use poison gas in the future, stating `` the use in war of asphyxiating, poisonous or other gases, and of all analogous liquids, materials or devices, has been justly condemned by the general opinion of the civilized world. '' Chemical weapons have been used in at least a dozen wars since the end of the First World War ; they were not used in combat on a large scale until Iraq used mustard gas and the more deadly nerve agents in the Halabja chemical attack near the end of the 8 - year Iran -- Iraq War. The full conflict 's use of such weaponry killed around 20,000 Iranian troops ( and injured another 80,000 ), around a quarter of the number of deaths caused by chemical weapons during the First World War. Effect on World War II All major combatants stockpiled chemical weapons during the Second World War, but the only reports of its use in the conflict were the Japanese use of relatively small amounts of mustard gas and lewisite in China, and very rare occurrences in Europe ( for example some mustard gas bombs were dropped on Warsaw on 3 September 1939, which Germany acknowledged in 1942 but indicated had been accidental ). Mustard gas was the agent of choice, with the British stockpiling 40,719 tons, the Soviets 77,400 tons, the Americans over 87,000 tons and the Germans 27,597 tons. The destruction of an American cargo ship containing mustard gas led to many casualties in Bari, Italy, in December 1943. In both Axis and Allied nations, children in school were taught to wear gas masks in case of gas attack. Germany developed the poison gases tabun, sarin, and soman during the war, and used Zyklon B in their extermination camps. Neither Germany nor the Allied nations used any of their war gases in combat, despite maintaining large stockpiles and occasional calls for their use. Poison gas played an important role in the Holocaust. Britain made plans to use mustard gas on the landing beaches in the event of an invasion of the United Kingdom in 1940. The United States considered using gas to support their planned invasion of Japan. Casualties The contribution of gas weapons to the total casualty figures was relatively minor. British figures, which were accurately maintained from 1916, recorded that 3 % of gas casualties were fatal, 2 % were permanently invalid and 70 % were fit for duty again within six weeks. It was remarked as a joke that if someone yelled ' Gas ', everyone in France would put on a mask... Gas shock was as frequent as shell shock. -- H. Allen, Towards the Flame, 1934 John Singer Sargent 's 1918 painting Gassed Gas ! GAS ! Quick, boys ! -- An ecstasy of fumbling, Fitting the clumsy helmets just in time ; But someone still was yelling out and stumbling, And flound'ring like a man in fire or lime... Dim, through the misty panes and thick green light, As under a green sea, I saw him drowning. In all my dreams, before my helpless sight, He plunges at me, guttering, choking, drowning. -- Wilfred Owen, `` Dulce et Decorum est '', 1917 Plate III, Pallid type of asphyxia from phosgene poisoning, with circulatory failure, American Red Cross and Medical Research Committee, An Atlas of Gas Poisoning, 1918 Death by gas was often slow and painful. According to Denis Winter ( Death 's Men, 1978 ), a fatal dose of phosgene eventually led to `` shallow breathing and retching, pulse up to 120, an ashen face and the discharge of four pints ( 2 litres ) of yellow liquid from the lungs each hour for the 48 of the drowning spasms. '' A common fate of those exposed to gas was blindness, chlorine gas or mustard gas being the main causes. One of the most famous First World War paintings, Gassed by John Singer Sargent, captures such a scene of mustard gas casualties which he witnessed at a dressing station at Le Bac - du - Sud near Arras in July 1918. ( The gases used during that battle ( tear gas ) caused temporary blindness and / or a painful stinging in the eyes. These bandages were normally water - soaked to provide a rudimentary form of pain relief to the eyes of casualties before they reached more organized medical help. ) The proportion of mustard gas fatalities to total casualties was low ; 2 % of mustard gas casualties died and many of these succumbed to secondary infections rather than the gas itself. Once it was introduced at the third battle of Ypres, mustard gas produced 90 % of all British gas casualties and 14 % of battle casualties of any type. Estimated gas casualties Nation Fatal Total ( Fatal & non-fatal ) Russia 56,000 419,340 Germany 9,000 200,000 France 8,000 190,000 British Empire ( includes Canada ) 8,109 188,706 Austria - Hungary 3,000 100,000 United States 1,462 72,807 Italy 4,627 60,000 Total 90,198 1,230,853 Mustard gas was a source of extreme dread. In The Anatomy of Courage ( 1945 ), Lord Moran, who had been a medical officer during the war, wrote : After July 1917 gas partly usurped the role of high explosive in bringing to head a natural unfitness for war. The gassed men were an expression of trench fatigue, a menace when the manhood of the nation had been picked over. Mustard gas did not need to be inhaled to be effective -- any contact with skin was sufficient. Exposure to 0.1 ppm was enough to cause massive blisters. Higher concentrations could burn flesh to the bone. It was particularly effective against the soft skin of the eyes, nose, armpits and groin, since it dissolved in the natural moisture of those areas. Typical exposure would result in swelling of the conjunctiva and eyelids, forcing them closed and rendering the victim temporarily blind. Where it contacted the skin, moist red patches would immediately appear which after 24 hours would have formed into blisters. Other symptoms included severe headache, elevated pulse and temperature ( fever ), and pneumonia ( from blistering in the lungs ). Many of those who survived a gas attack were scarred for life. Respiratory disease and failing eyesight were common post-war afflictions. Of the Canadians who, without any effective protection, had withstood the first chlorine attacks during Second Ypres, 60 % of the casualties had to be repatriated and half of these were still unfit by the end of the war, over three years later. Many of those who were fairly soon recorded as fit for service were left with scar tissue in their lungs. This tissue was susceptible to tuberculosis attack. It was from this that many of the 1918 casualties died, around the time of the Second World War, shortly before sulfa drugs became widely available for its treatment. British casualties British forces gas casualties on the Western Front Date Agent Casualties ( official ) Fatal Non-fatal April -- May 1915 Chlorine 350 7,000 May 1915 -- June 1916 Lachrymants 0 0 December 1915 -- August 1916 Chlorine 1,013 4,207 July 1916 -- July 1917 Various 532 8,806 July 1917 -- November 1918 Mustard gas 4,086 160,526 April 1915 -- November 1918 Total 5,981 180,539 A British nurse treating mustard gas cases recorded : They can not be bandaged or touched. We cover them with a tent of propped - up sheets. Gas burns must be agonizing because usually the other cases do not complain even with the worst wounds but gas cases are invariably beyond endurance and they can not help crying out. A postmortem account from the British official medical history records one of the British casualties : Case four. Aged 39 years. Gassed 29 July 1917. Admitted to casualty clearing station the same day. Died about ten days later. Brownish pigmentation present over large surfaces of the body. A white ring of skin where the wrist watch was. Marked superficial burning of the face and scrotum. The larynx much congested. The whole of the trachea was covered by a yellow membrane. The bronchi contained abundant gas. The lungs fairly voluminous. The right lung showing extensive collapse at the base. Liver congested and fatty. Stomach showed numerous submucous haemorrhages. The brain substance was unduly wet and very congested. Civilian casualties The distribution of gas cloud casualties was not limited to the front. Nearby towns were at risk from winds blowing the poison gases through. Civilians rarely had a warning system to alert their neighbours of the danger and often did not have access to effective gas masks. When the gas came to the towns it could easily get into houses through open windows and doors. An estimated 100,000 - 260,000 civilian casualties were caused by chemical weapons during the conflict and tens of thousands ( along with military personnel ) died from scarring of the lungs, skin damage, and cerebral damage in the years after the conflict ended. Many commanders on both sides knew that such weapons would cause major harm to civilians as wind would blow poison gases into nearby civilian towns but nonetheless continued to use them throughout the war. British Field Marshal Sir Douglas Haig wrote in his diary : `` My officers and I were aware that such weapon would cause harm to women and children living in nearby towns, as strong winds were common on the battlefront. However, because the weapon was to be directed against the enemy, none of us were overly concerned at all. '' Countermeasures A Smelling Case to allow officers to identify the gas by smell and thus act appropriately for protection and treatment None of the First World War 's combatants were prepared for the introduction of poison gas as a weapon. Once gas was introduced, development of gas protection began and the process continued for much of the war producing a series of increasingly effective gas masks. Even at Second Ypres, Germany, still unsure of the weapon 's effectiveness, only issued breathing masks to the engineers handling the gas. At Ypres a Canadian medical officer, who was also a chemist, quickly identified the gas as chlorine and recommended that the troops urinate on a cloth and hold it over their mouth and nose. The first official equipment issued was similarly crude ; a pad of material, usually impregnated with a chemical, tied over the lower face. To protect the eyes from tear gas, soldiers were issued with gas goggles. British Vickers machine gun crew wearing PH gas helmets with exhaust tubes The next advance was the introduction of the gas helmet -- basically a bag placed over the head. The fabric of the bag was impregnated with a chemical to neutralize the gas -- the chemical would wash out into the soldier 's eyes whenever it rained. Eye - pieces, which were prone to fog up, were initially made from talc. When going into combat, gas helmets were typically worn rolled up on top of the head, to be pulled down and secured about the neck when the gas alarm was given. The first British version was the Hypo helmet, the fabric of which was soaked in sodium hyposulfite ( commonly known as `` hypo '' ). The British P gas helmet, partially effective against phosgene and with which all infantry were equipped with at Loos, was impregnated with sodium phenolate. A mouthpiece was added through which the wearer would breathe out to prevent carbon dioxide build - up. The adjutant of the 1 / 23rd Battalion, The London Regiment, recalled his experience of the P helmet at Loos : The goggles rapidly dimmed over, and the air came through in such suffocatingly small quantities as to demand a continuous exercise of will - power on the part of the wearers. A modified version of the P Helmet, called the PH Helmet, was issued in January 1916, and was impregnated with hexamethylenetetramine to improve the protection against phosgene. Australian infantry wearing Small Box Respirators, Ypres, September 1917 Self - contained box respirators represented the culmination of gas mask development during the First World War. Box respirators used a two - piece design ; a mouthpiece connected via a hose to a box filter. The box filter contained granules of chemicals that neutralised the gas, delivering clean air to the wearer. Separating the filter from the mask enabled a bulky but efficient filter to be supplied. Nevertheless, the first version, known as the Large Box Respirator ( LBR ) or `` Harrison 's Tower '', was deemed too bulky -- the box canister needed to be carried on the back. The LBR had no mask, just a mouthpiece and nose clip ; separate gas goggles had to be worn. It continued to be issued to the artillery gun crews but the infantry were supplied with the `` Small Box Respirator '' ( SBR ). The Small Box Respirator featured a single - piece, close - fitting rubberized mask with eye - pieces. The box filter was compact and could be worn around the neck. The SBR could be readily upgraded as more effective filter technology was developed. The British - designed SBR was also adopted for use by the American Expeditionary Force. The SBR was the prized possession of the ordinary infantryman ; when the British were forced to retreat during the German Spring Offensive of 1918, it was found that while some troops had discarded their rifles, hardly any had left behind their respirators. Horses and mules were important methods of transport that could be endangered if they came into close contact with gas. This was not so much of a problem until it became common to launch gas great distances. This caused researchers to develop masks that could be used on animals such as dogs, horses, mules, and even carrier pigeons. For mustard gas, which could cause severe damage by simply making contact with skin, no effective countermeasure was found during the war. The kilt - wearing Scottish regiments were especially vulnerable to mustard gas injuries due to their bare legs. At Nieuwpoort in Flanders some Scottish battalions took to wearing women 's tights beneath the kilt as a form of protection. Gas alert by Arthur Streeton, 1918 Gas alert procedure became a routine for the front - line soldier. To warn of a gas attack, a bell would be rung, often made from a spent artillery shell. At the noisy batteries of the siege guns, a compressed air strombus horn was used, which could be heard nine miles ( 14 km ) away. Notices would be posted on all approaches to an affected area, warning people to take precautions. Other British attempts at countermeasures were not so effective. An early plan was to use 100,000 fans to disperse the gas. Burning coal or carborundum dust was tried. A proposal was made to equip front - line sentries with diving helmets, air being pumped to them through a 100 ft ( 30 m ) hose. The effectiveness of all countermeasures is apparent. In 1915, when poison gas was relatively new, less than 3 % of British gas casualties died. In 1916, the proportion of fatalities jumped to 17 %. By 1918, the figure was back below 3 %, though the total number of British gas casualties was now nine times the 1915 levels. Various gas masks employed on the Western Front during the war Delivery systems This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. ( January 2012 ) A British cylinder release at Montauban on the Somme, June 1916 -- part of the preparation for the Battle of the Somme. The first system employed for the mass delivery of gas involved releasing the gas cylinders in a favourable wind such that it was carried over the enemy 's trenches. The Hague Convention of 1899 prohibited the use of poisons gasses delivered by projectiles. The main advantage of this method was that it was relatively simple and, in suitable atmospheric conditions, produced a concentrated cloud capable of overwhelming the gas mask defences. The disadvantages of cylinder releases were numerous. First and foremost, delivery was at the mercy of the wind. If the wind was fickle, as was the case at Loos, the gas could backfire, causing friendly casualties. Gas clouds gave plenty of warning, allowing the enemy time to protect themselves, though many soldiers found the sight of a creeping gas cloud unnerving. Gas clouds had limited penetration, only capable of affecting the front - line trenches before dissipating. Finally, the cylinders had to be emplaced at the very front of the trench system so that the gas was released directly over no man 's land. This meant that the cylinders had to be manhandled through communication trenches, often clogged and sodden, and stored at the front where there was always the risk that cylinders would be prematurely breached during a bombardment. A leaking cylinder could issue a telltale wisp of gas that, if spotted, would be sure to attract shellfire. German gas attack on the eastern front. A British chlorine cylinder, known as an `` oojah '', weighed 190 lb ( 86 kg ), of which 60 lb ( 27 kg ) was chlorine gas, and required two men to carry. Phosgene gas was introduced later in a cylinder, known as a `` mouse '', that weighed 50 lb ( 23 kg ). Delivering gas via artillery shell overcame many of the risks of dealing with gas in cylinders. The Germans, for example, used 5.9 - inch ( 150 mm ) artillery shells. Gas shells were independent of the wind and increased the effective range of gas, making anywhere within reach of the guns vulnerable. Gas shells could be delivered without warning, especially the clear, nearly odourless phosgene -- there are numerous accounts of gas shells, landing with a `` plop '' rather than exploding, being initially dismissed as dud HE or shrapnel shells, giving the gas time to work before the soldiers were alerted and took precautions. Loading a battery of Livens gas projectors The main flaw associated with delivering gas via artillery was the difficulty of achieving a killing concentration. Each shell had a small gas payload and an area would have to be subjected to a saturation bombardment to produce a cloud to match cylinder delivery. Mustard gas did not need to form a concentrated cloud and hence artillery was the ideal vehicle for delivery of this battlefield pollutant. The solution to achieving a lethal concentration without releasing from cylinders was the `` gas projector '', essentially a large - bore mortar that fired the entire cylinder as a missile. The British Livens projector ( invented by Captain W.H. Livens in 1917 ) was a simple device ; an 8 - inch ( 200 mm ) diameter tube sunk into the ground at an angle, a propellant was ignited by an electrical signal, firing the cylinder containing 30 or 40 lb ( 14 or 18 kg ) of gas up to 1,900 metres. By arranging a battery of these projectors and firing them simultaneously, a dense concentration of gas could be achieved. The Livens was first used at Arras on 4 April 1917. On 31 March 1918 the British conducted their largest ever `` gas shoot '', firing 3,728 cylinders at Lens. Unexploded weapons Phosgene delivery system unearthed at the Somme, 2006 Over 16,000,000 acres ( 65,000 km ) of France had to be cordoned off at the end of the war because of unexploded ordnance. About 20 % of the chemical shells were duds, and approximately 13 million of these munitions were left in place. This has been a serious problem in former battle areas from immediately after the end of the War until the present. Shells may be, for instance, uncovered when farmers plough their fields ( termed the ' iron harvest ' ), and are also regularly discovered when public works or construction work is done. Another difficulty is the current stringency of environmental legislation. In the past, a common method of getting rid of unexploded chemical ammunition was to detonate or dump it at sea ; this is currently prohibited in most countries. The problems are especially acute in some northern regions of France. The French government no longer disposes of chemical weapons at sea. For this reason, piles of untreated chemical weapons accumulated. In 2001, it became evident that the pile stored at a depot in Vimy was unsafe ; the inhabitants of the neighbouring town were evacuated, and the pile moved, using refrigerated trucks and under heavy guard, to a military camp in Suippes. The capacity of the plant is meant to be 25 tons per year ( extensible to 80 tons at the beginning ), for a lifetime of 30 years. Germany has to deal with unexploded ammunition and polluted lands resulting from the explosion of an ammunition train in 1919. Aside from unexploded shells, there have been claims that poison residues have remained in the local environment for an extended period, though this is unconfirmed ; well known but unverified anecdotes claim that as late as the 1960s trees in the area retained enough mustard gas residue to injure farmers or construction workers who were clearing them. Gases used Name First use Type Used by Xylyl bromide 1914 Lachrymatory, toxic Both Chlorine 1915 Corrosive. Lung irritant Both Phosgene 1915 Irritant - Skin and mucous membranes. Corrosive, toxic Both Benzyl bromide 1915 Lachrymatory Central Powers Chloromethyl chloroformate 1915 Irritant - Eyes, skin, lungs Both Trichloromethyl chloroformate 1916 Severe irritant, causes burns Both Chloropicrin 1916 Irritant, lachrymatory, toxic Both Stannic chloride 1916 Severe irritant, causes asphyxiating Allies Ethyl iodoacetate 1916 Lachrymatory, toxic Allies Bromoacetone 1916 Lachrymatory, irritant Both Monobromomethyl ethyl ketone 1916 Lachrymatory, irritant Central Powers Acrolein 1916 Lachrymatory, toxic Central Powers Hydrogen cyanide ( Prussic acid ) 1916 Toxic, asphyxiant Allies Hydrogen sulfide ( sulphuretted hydrogen ) 1916 Irritant, toxic Allies Diphenylchloroarsine ( Diphenyl chlorasine ) 1917 Irritant / Sternutatory ( causes sneezing ) Central Powers α - chlorotoluene ( Benzyl chloride ) 1917 Irritant, lachrymatory Central Powers Mustard gas ( Bis ( 2 - chloroethyl ) sulfide ) 1917 Vesicant ( blistering agent ), lung irritant Both Bis ( chloromethyl ) ether ( dichloromethyl ether ) 1918 Irritant, can blur vision Central Powers Ethyldichloroarsine 1918 Vesicant Central Powers N - Ethylcarbazole 679 1918 Irritant Central Powers Long - term Health effects Soldiers who claimed to have been exposed to chemical warfare have often presented with unusual medical conditions which has led to much controversy. The lack of information has left doctors, patients, and their families in the dark in terms of prognosis and treatment. Nerve agents such as sarin, tabun, and soman are believed to have the most significant long - term health effects. Chronic fatigue and memory loss have been reported to last up to three years after exposure. In the years following World War One, there were many conferences held in attempts to abolish the use of chemical weapons all together, such as the Washington Naval Conference ( 1921 -- 22 ), Geneva Conference ( 1923 -- 25 ) and the World Disarmament Conference ( 1933 ). The United States was an original signatory of the Geneva Protocol in 1925, but the US Senate did not ratify it until 1975. Although the health effects are generally chronic in nature, the exposures were generally acute. A positive correlation has been proven between exposure to mustard agents and skin cancers, other respiratory and skin conditions, leukemia, several eye conditions, bone marrow depression and subsequent immunosuppression, psychological disorders and sexual dysfunction. Chemicals used in the production of chemical weapons have also left residues in the soil where the weapons were used. The chemicals that have been detected can cause cancer and can affect the brain, blood, liver, kidneys and skin. Despite the evidence in support of long - term health effects, there are studies that show just the opposite. Some US veterans who were closely affected by chemical weapons showed no neurological evidence in the following years. These same studies showed that one single contact with chemical weapons would be enough to cause long - term health effects. Notes Jump up ^ The US reportedly had about 135,000 tons of chemical warfare agents during WW II ; Germany had 70,000 tons, Britain 40,000 and Japan 7,500 tons. The German nerve gases were deadlier than the old - style suffocants ( chlorine, phosgene ) and blistering agents ( mustard gas ) in Allied stockpiles. Churchill, and several American Generals reportedly called for their use against Germany and Japan, respectively ( Weber, 1985 ). Jump up ^ See the Convention for the Prevention of Marine Pollution by Dumping from Ships and Aircraft and the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter. References Jump up ^ Adrienne Mayor ( 29 September 2003 ). Greek Fire, Poison Arrows and Scorpion Bombs : Biological and Chemical Warfare in the Ancient World. Overlook Books. ISBN 1 - 58567 - 348 - X. Jump up ^ Andre Richardt ( 26 December 2012 ). CBRN Protection : Managing the Threat of Chemical, Biological, Radioactive and Nuclear Weapons. Wiley - VCH. ISBN 978 - 3 - 527 - 32413 - 2. Jump up ^ Reddy, Chris ( 2 April 2007 ). `` The Growing Menace of Chemical War ''. Woods Hole Oceanographic Institution. Retrieved 30 July 2007. Jump up ^ Saffo, Paul ( 2000 ). `` Paul Saffo presentation ''. Woods Hole Oceanographic Institution. Archived from the original on 27 September 2007. Retrieved 30 July 2007. Jump up ^ Telford Taylor ( 1 November 1993 ). The Anatomy of the Nuremberg Trials : A Personal Memoir. Little, Brown and Company. ISBN 0 - 316 - 83400 - 9. Jump up ^ Thomas Graham ; Damien J. Lavera ( May 2003 ). Cornerstones of Security : Arms Control Treaties in the Nuclear Era. University of Washington Press. pp. 7 -- 9. ISBN 0 - 295 - 98296 - 9. Jump up ^ Haber, Ludwig Fritz ( 1986 ). The Poisonous Cloud : Chemical Warfare in the First World War. Oxford University press. ISBN 0 - 19 - 858142 - 4. ^ Jump up to : Heller, Charles E ( September 1984 ). `` Chemical Warfare in World War I : The American Experience, 1917 -- 1918 ''. US Army Command and General Staff College Jump up ^ Taylor, L.B. ; Taylor, C.L. ( 1992 ). Chemical and Biological Warfare ( Revised ed. ). Franklin Watts. ISBN 0 - 531 - 13029 - 0. Jump up ^ Romano, James A. ; Lukey, Brian J. ; Salem, Harry ( 2007 ). Chemical warfare agents : chemistry, pharmacology, toxicology, and therapeutics ( 2nd ed. ). CRC Press. p. 5. ISBN 1 - 4200 - 4661 - 6. Jump up ^ Legg, J. ; Parker, G. ( 2002 ). `` The Germans develop a new weapon : the gas cloud ''. The Great War. Retrieved 6 August 2007. Jump up ^ `` Fritz Haber ''. Science History Institute. Retrieved 20 March 2018. Jump up ^ Abelshauser, Werner ( 2003 ). German Industry and Global Enterprise, BASF : The History of a Company. Cambridge University Press. ISBN 0 - 521 - 82726 - 4. Jump up ^ Aksulu, N. Melek ( May 2006 ). `` Die Feldpostbriefe Karl v. Zinglers aus dem Ersten Weltkrieg '' ( PDF ). Nobilitas, Zeitschrift für deutsche Adelsforschung Folge. IX ( 41 ) : 57. Archived from the original ( PDF ) on 5 March 2009. Retrieved 28 December 2008. Rousselare 2 Januar 15... Auf anderen Kriegsschauplätzen ist es ja auch nicht besser und die Wirkung von unserem Chlor soll ja sehr gut sein. Es sollen 140 englische Offiziere erledigt worden sein. Es ist doch eine furchtbare Waffe... Jump up ^ General R. Hure, page 283, L'Armee d'Afrique 1830 - 1962, Charles - Lavauzelle 1972 Jump up ^ Tucker, Jonathan B. ( 2006 ). War of Nerves : Chemical Warfare from World War I to Al - Queda. Pantheon Books. ISBN 0 - 375 - 42229 - 3. Jump up ^ Staff ( 29 July 2004 ). `` On the Western Front, Ypres 1915 ''. Veteran Affairs Canada. Retrieved 8 April 2008. Jump up ^ Lefebure, Victor ; Wilson, Henry ( 2004 ). The Riddle of the Rhine : Chemical Strategy in Peace and War. Kessinger Publishing. ISBN 1 - 4179 - 3546 - 4. Jump up ^ Edmonds and Wynne ( 1927 ) : p. 289. ^ Jump up to : Kojevnikov, A. ( June 2002 ). `` The Great War, the Russian Civil War, and the Invention of Big Science '' ( PDF ). Science in Context. 15 ( 2 ) : 239 -- 275. doi : 10.1017 / S0269889702000443. PMID 12467271. Jump up ^ Edmonds and Wynne ( 1927 ) : pp. 177 -- 8. Jump up ^ For example, see : Chattaway, Frederick Daniel ( 22 December 1908 ). `` The Action of Chlorine upon Urea Whereby a Dichloro Urea is Produced ''. Proceedings of the Royal Society of London. 81 ( 549 ) : 381 -- 388. doi : 10.1098 / rspa. 1908.0094. JSTOR 93011. Jump up ^ O'Leary, Donal ( 2000 ). `` Chlorine ''. University College Cork. Retrieved 2 August 2007. Jump up ^ Jones, E. ; Everitt, B. ; Ironside, S. ; Palmer, I. ; Wessely, S. ( 2008 ). `` Psychological effects of chemical weapons : a follow - up study of First World War veterans ''. Psychological Medicine. 38 ( 10 ) : 1419 -- 26. doi : 10.1017 / S003329170800278X. PMID 18237455. Retrieved 29 April 2009. ^ Jump up to : Edmonds and Wynne ( 1927 ) : p. 217. Jump up ^ Cook, Tim ( 1999 ). No Place to Run : The Canadian Corps and Gas Warfare in the First World War. UBC Press. p. 37. ISBN 0 - 7748 - 0740 - 7. Jump up ^ `` Gas ''. Weaponry. First World War. Jump up ^ Warner, Philip ( 2000 ). The Battle of Loos. Wordsworth Military Library. Wordsworth Editions. p. 37. ISBN 1 - 84022 - 229 - 8. Jump up ^ Nye, Mary Jo ( 1999 ). Before big science : the pursuit of modern chemistry and physics, 1800 -- 1940. Harvard University Press. p. 193. ISBN 0 - 674 - 06382 - 1. ^ Jump up to : Staff ( 2004 ). `` Choking Agent : CG ''. CBWInfo. Archived from the original on 14 August 2007. Retrieved 30 July 2007. Jump up ^ Kiester, Edwin ; et al. ( 2007 ). An Incomplete History of World War I. 1. Murdoch Books. p. 74. ISBN 1 - 74045 - 970 - 9. Jump up ^ Staff ( 22 February 2006 ). `` Facts About Phosgene ''. CDC. Archived from the original on 17 April 2003. Retrieved 23 May 2008. Jump up ^ Haber, Ludwig Fritz ( 1986 ). The poisonous cloud : chemical warfare in the First World War. Oxford University Press. p. 70. ISBN 0 - 19 - 858142 - 4. Jump up ^ Patnaik, Pradyot ( 2007 ). A comprehensive guide to the hazardous properties of chemical substances ( 3rd ed. ). Wiley - Interscience. p. 85. ISBN 0 - 471 - 71458 - 5. Jump up ^ `` A SHORT HISTORY OF CHEMICAL WARFARE DURING WORLD WAR I ''. Archived from the original on 23 October 1999. Retrieved 18 September 2013. CS1 maint : BOT : original - url status unknown ( link ) Jump up ^ Rauchensteiner, Manfried, The First World War and the End of the Habsburg Monarchy, 1914 - 1918 ( Vienna, Austria : Böhlau Verlag, 2014 ), pp. 543 - 544. Jump up ^ Hoenig, Steven L. ( 2002 ). Handbook of Chemical Warfare and Terrorism. Westport, Connecticut : Greenwood Press. ISBN 0 - 313 - 32407 - 7. Jump up ^ Staff ( 22 February 2006 ). `` Facts About Sulfur Mustard ''. Centers for Disease Control and Prevention. Archived from the original on 9 August 2006. Retrieved 10 August 2006. Jump up ^ Sidell, F.R. ; Urbanetti, J.S. ; Smith, W.J. ; Hurst, C.G. ( 1997 ). `` Chapter 7. Vesicants ''. In Sidell, F.R. ; Takafuji, E.T. ; Franz, D.R. Medical Aspects of Chemical and Biological Warfare. Office of The Surgeon General, Department of the Army, United States of America. ISBN 99973 - 209 - 1 - 3. LCCN 97022242. OCLC 489185423. Retrieved 8 August 2007. Jump up ^ Brittain, Vera ( 1933 ). Testament of Youth : An Autobiographical Study of the Years 1900 -- 1925. New York : The Macmillan Company. ISBN 0 - 14 - 012251 - 6. ^ Jump up to : Duffy, Michael ( 22 August 2009 ). `` Weapons of War - Poison Gas ''. firstworldwar.com. Retrieved 25 October 2009. Jump up ^ Dolev, Eran ; Lillywhite, Louis ( 2007 ). Allenby 's military medicine : life and death in World War I Palestine. I.B. Tauris. pp. 37 -- 38. ISBN 1 - 84511 - 290 - 3. Jump up ^ Edited by David Large. The Port of Bristol, 1848 - 1884. CS1 maint : Extra text : authors list ( link ) Jump up ^ `` Photographic Archive of Avonmouth Bristol BS11 ''. BristolPast.co.uk. Retrieved 12 May 2014. Jump up ^ Crowell, Benedict ; Wilson, Robert Forrest ( 1921 ). The Armies of Industry : Our Nation 's Manufacture of Munitions for a World in Arms, 1917 -- 1918. 5. Yale University Press. pp. 491, 500. ISBN 1 - 60105 - 114 - X. Retrieved 8 December 2008. ^ Jump up to : Gross, Daniel A. ( Spring 2015 ). `` Chemical Warfare : From the European Battlefield to the American Laboratory ''. Distillations. 1 ( 1 ) : 16 -- 23. Retrieved 20 March 2018. Jump up ^ Lockwood, John C. ( 2003 ). `` Chapter 3. The Earth 's Climates ''. In Hewitt, C.N. ; Jackson, A.V. Handbook of Atmospheric Science : Principles and Applications. Blackwell Publishing. pp. 72 -- 74. ISBN 0 - 632 - 05286 - 4. Jump up ^ Addison, James Thayer ( 1919 ). The story of the First gas regiment. Boston and New York : Houghton Mifflin company. pp. 50, 146, 158, 168. Retrieved 14 April 2017. Jump up ^ Annual Report of the Secretary of War, 1919, pages 4386 - 87 Jump up ^ D. Hank Ellison ( 24 August 2007 ). Handbook of Chemical and Biological Warfare Agents, Second Edition. CRC Press. p. 456. ISBN 0 - 8493 - 1434 - 8. Jump up ^ Hershberg, James G. ( 1993 ). James B. Conant : Harvard to Hiroshima and the making of the nuclear age. Stanford, Cal. : Stanford University Press. p. 47. ISBN 0 - 8047 - 2619 - 1. Jump up ^ Schneider, Barry R. ( 28 February 1999 ). Future War and Counterproliferation : U.S. Military Responses to NBC. Praeger, p. 84 ; ISBN 0 - 275 - 96278 - 4 Jump up ^ `` Winston Churchill 's shocking use of chemical weapons ''. The Guardian. 1 September 2013. Retrieved 17 April 2017. ^ Jump up to : `` Blister Agent : Sulfur Mustard ( H, HD, HS ) ''. CBWInfo. 2005. Archived from the original on 24 July 2007. Retrieved 30 July 2007. ^ Jump up to : Rosenheck, Dan ( 25 August 2003 ). `` WMDs : the biggest lie of all ''. New Statesman. 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Jump up ^ `` Chemical Weapons against Invasion ''. Council for British Archaeology. Archived from the original on 9 July 2007. Retrieved 30 July 2007. Jump up ^ Bernstein, Barton J. ( August -- September 1985 ). `` Why We Did n't Use Poison Gas in World War II ''. American Heritage. 36 ( 5 ). Archived from the original on 29 September 2007. Retrieved 29 April 2009. Jump up ^ Wilson, Charles McMoran ( Lord Moran ) ( 1945 ). The Anatomy of Courage ( 1st ed. ). London : Constable. Jump up ^ Cook, Tim ( 1999 ). No Place to Run : The Canadian Corps and Gas Warfare in the First World War. UBC Press. ISBN 0 - 7748 - 0740 - 7. Jump up ^ Harris, T ; Paxman, J. ( 2002 ). A higher form of killing : the secret history of chemical and biological warfare. Random House, Inc. ISBN 0 - 8129 - 6653 - 8. Jump up ^ L.F. Haber ( 20 February 1986 ). The Poisonous Cloud : Chemical Warfare in the First World War. Clarendon Press. pp. 106 -- 108. ISBN 0 - 1985 - 8142 - 4. Jump up ^ Joel A. Vilensky ( 20 February 1986 ). Dew of Death : The Story of Lewisite, America 's World War I Weapon of Mass. Indiana University Press. pp. 78 -- 80. ISBN 0 - 2533 - 4612 - 6. Jump up ^ D. Hank Ellison ( 24 August 2007 ). Handbook of Chemical and Biological Warfare Agents, Second Edition. CRC Press. pp. 567 -- 570. ISBN 0 - 8493 - 1434 - 8. Jump up ^ Max Boot ( 16 August 2007 ). War Made New : Weapons, Warriors, and the Making of the Modern World. Gotham. pp. 245 -- 250. ISBN 1 - 5924 - 0315 - 8. Jump up ^ Warner, Philip ( 2000 ). The Battle of Loos. Wordsworth Editions. p. 103. ISBN 1 - 84022 - 229 - 8. Jump up ^ Fitzgerald, Gerard ( April 2008 ). `` Chemical Warfare and Medical Response During World War I ''. American Journal of Public Health. 98 ( 4 ) : 611 -- 625. doi : 10.2105 / AJPH. 2007.11930. PMC 2376985. PMID 18356568. Jump up ^ Croddy, Eric ( 2002 ). Chemical and Biological Warfare : A Comprehensive Survey for the Concerned Citizen. Springer. ISBN 0 - 387 - 95076 - 1. Jump up ^ Bothe, Michael ; Ronzitti, Natalino ; Rosas, Allan ( 1998 ). The new Chemical Weapons Convention -- implementation and prospects. Martinus Nijhoff Publishers. p. 208. ISBN 90 - 411 - 1099 - 2 Jump up ^ J.C. ( 17 April 2001 ). `` Sécurité. Les 55 tonnes d'obus chimiques sont stockées au camp militaire de Suippes '' ( in French ). L'Humanité. Archived from the original on 21 September 2006. Retrieved 30 July 2007. ^ Jump up to : J.C. ( 17 April 2001 ). `` Déminage '' ( in French ). Sénat. Retrieved 30 July 2007. Jump up ^ Browne, Malcomb W. ( 22 March 1995 ). `` Terror in Tokyo : The Poison ; Sarin Just One of Many Deadly Gases Terrorists Could Use ''. The New York Times. Retrieved 29 April 2009. ^ Jump up to : Cowell, E.M. ( October 1939 ). `` Chemical Warfare and the Doctor ''. The British Medical Journal. 2 ( 4109 ) : 736 -- 738. doi : 10.1136 / bmj. 2.4109. 736. ^ Jump up to : Gibson, Adelno ( July 1937 ). `` Chemical Warfare as Developed During the World War -- Probable Future Development ''. Bulletin of the New York Academy of Medicine. 13 ( 7 ) : 397 -- 421. PMC 1966130. PMID 19312026. Jump up ^ Glyn Volans, `` Long - term effects of chemical weapons, '' The Lancet, 360, ( December 2002 ) : 36. Jump up ^ Mary Fox, Frank Curriero, Kathryn Kulbicki, Beth Resnick, Thomas Burke, `` Evaluating the Community Health Legacy of WWI Chemical Weapons Testing, '' Journal of Community Health, 35, ( 18 November 2009 ) : 96. Jump up ^ Mary Fox, Frank Curriero, Kathryn Kulbicki, Beth Resnick, Thomas Burke, `` Evaluating the Community Health Legacy of WWI Chemical Weapons Testing, '' Journal of Community Health, 35, ( 18 November 2009 ) : 96 - 97. Jump up ^ James R. Riddle, `` Chemical Warfare and the Gulf War : A Review of the Impact on Gulf Veterans ' Health, '' Military Medicine, 168, ( August 2003 ) : 607. Further reading Freemantle, M. ( 2012 ). Gas ! GAS ! Quick, boys ! How Chemistry Changed the First World War. The History Press. ISBN 978 - 0 - 7524 - 6601 - 9. MacPherson, W.G. ; Herringham, W.P. ; Elliott, T.R. ; Balfour, A. ( 1923 ). Medical Services : Diseases of the War : Including the Medical Aspects of Aviation and Gas Warfare and Gas Poisoning in Tanks and Mines. History of the Great War Based on Official Documents by Direction of the Historical Section of the Committee of Imperial Defence. II. London : HMSO. OCLC 769752656. Retrieved 19 October 2014. External links Faith, Thomas I. : Gas Warfare, in : 1914 - 1918 - online. International Encyclopedia of the First World War. Chemical Weapons in World War I Gas Warfare Gas - Poisoning, by Arthur Hurst, M.A., MD ( Oxon ), FRCP 1917 effects of chlorine gas poisoning Understanding Chemical Weapons in the First World War World War I Home fronts Theatres European Balkans Western Front Eastern Front Italian Front Middle Eastern Gallipoli Sinai and Palestine Caucasus Persia Mesopotamia South Arabia African South West East Kamerun Togoland North Asian and Pacific Tsingtao German New Guinea and Samoa At sea North Atlantic U-boat campaign Mediterranean North Sea Baltic Indian, Pacific and South Atlantic Oceans Papeete Madras Penang Cocos Coronel Falkland Islands Más a Tierra Principal participants ( people ) Entente powers Belgium Brazil China France French Empire Greece Italy Japan Montenegro Portuguese Empire Romania Russia Russian Empire Russian Republic Serbia United Kingdom British Empire United States Central Powers Germany Austria - Hungary Ottoman Empire Bulgaria Timeline Pre-War conflicts Scramble for Africa ( 1880 -- 1914 ) Russo - Japanese War ( 1905 ) First Moroccan ( Tangier ) Crisis ( 1905 -- 06 ) Agadir Crisis ( 1911 ) Italo - Turkish War ( 1911 -- 12 ) French conquest of Morocco ( 1911 -- 12 ) First Balkan War ( 1912 -- 13 ) Second Balkan War ( 1913 ) Prelude Origins Sarajevo assassination Anti-Serb riots in Sarajevo July Crisis Autumn 1914 Battle of the Frontiers Battle of Cer First Battle of the Marne Siege of Tsingtao Battle of Tannenberg Battle of Galicia Battle of the Masurian Lakes Battle of Kolubara Battle of Sarikamish Race to the Sea First Battle of Ypres 1915 Second Battle of the Masurian Lakes Second Battle of Ypres Battle of Gallipoli Second Battle of Artois Battles of the Isonzo Gorlice -- Tarnów Offensive Great Retreat Second Battle of Champagne Kosovo Offensive Siege of Kut Battle of Loos 1916 Erzurum Offensive Battle of Verdun Lake Naroch Offensive Battle of Asiago Battle of Jutland Battle of the Somme first day Brusilov Offensive Baranovichi Offensive Battle of Romani Monastir Offensive Battle of Transylvania 1917 Capture of Baghdad First Battle of Gaza Zimmermann Telegram Second Battle of Arras Second Battle of the Aisne Kerensky Offensive Third Battle of Ypres ( Passchendaele ) Battle of Mărășești Battle of Caporetto Southern Palestine Offensive Battle of Cambrai Armistice of Erzincan 1918 Operation Faustschlag Treaty of Brest - Litovsk Spring Offensive Battle of Goychay Battle of Aghsu Battle of Kyurdamir Second Battle of the Marne Battle of Baku Hundred Days Offensive Vardar Offensive Battle of Megiddo Third Transjordan attack Meuse - Argonne Offensive Battle of Vittorio Veneto Battle of Aleppo Armistice of Salonica Armistice of Mudros Armistice of Villa Giusti Armistice with Germany Other conflicts Mexican Revolution ( 1910 -- 20 ) Somaliland Campaign ( 1910 -- 20 ) Libyan resistance movement ( 1911 -- 43 ) Maritz Rebellion ( 1914 -- 15 ) Zaian War ( 1914 -- 21 ) Indo - German Conspiracy ( 1914 -- 19 ) Senussi Campaign ( 1915 -- 16 ) Volta - Bani War ( 1915 -- 17 ) Easter Rising ( 1916 ) Anglo - Egyptian Darfur Expedition ( 1916 ) Kaocen Revolt ( 1916 -- 17 ) Central Asian Revolt ( 1916 - 17 ) Russian Revolution ( 1917 ) Finnish Civil War ( 1918 ) Post-War conflicts Russian Civil War ( 1917 -- 21 ) Ukrainian -- Soviet War ( 1917 -- 21 ) Armenian -- Azerbaijani War ( 1918 -- 20 ) Georgian -- Armenian War ( 1918 ) German Revolution ( 1918 -- 19 ) Revolutions and interventions in Hungary ( 1918 -- 20 ) Hungarian -- Romanian War ( 1918 -- 19 ) Greater Poland Uprising ( 1918 -- 19 ) Estonian War of Independence ( 1918 -- 20 ) Latvian War of Independence ( 1918 -- 20 ) Lithuanian Wars of Independence ( 1918 -- 20 ) Third Anglo - Afghan War ( 1919 ) Egyptian Revolution ( 1919 ) Polish -- Ukrainian War ( 1918 -- 19 ) Polish -- Soviet War ( 1919 -- 21 ) Irish War of Independence ( 1919 -- 21 ) Turkish War of Independence Greco - Turkish War ( 1919 -- 22 ) Turkish -- Armenian War ( 1920 ) Iraqi revolt ( 1920 ) Polish -- Lithuanian War ( 1920 ) Vlora War ( 1920 ) Franco - Syrian War ( 1920 ) Soviet -- Georgian War ( 1921 ) Irish Civil War ( 1922 -- 23 ) Aspects Opposition Pacifism Anti-war movement Deployment Schlieffen Plan ( German ) Plan XVII ( French ) Warfare Military engagements Naval warfare Convoy system Air warfare Cryptography Room 40 Horse use Poison gas Railways Strategic bombing Technology Trench warfare Total war Christmas truce Last surviving veterans Civilian impact Atrocities Prisoners Casualties Economic history 1918 flu pandemic Destruction of Kalisz Rape of Belgium German occupation of Belgium German occupation of Luxembourg German occupation of northeastern France Ober Ost Ottoman people Armenian Genocide Assyrian genocide Pontic Greek genocide Urkun ( Kyrgyzstan ) Blockade of Germany Women Australia Popular culture German prisoners of war in the United States Agreements Partition of the Ottoman Empire Sykes -- Picot Agreement Agreement of Saint - Jean - de-Maurienne French - Armenian Agreement Damascus Protocol Paris Peace Conference Venizelos -- Tittoni agreement Treaties Treaty of Brest - Litovsk Treaty of Lausanne Treaty of London Treaty of Neuilly Treaty of St. Germain Treaty of Sèvres Treaty of Trianon Treaty of Versailles Consequences Aftermath `` Fourteen Points '' League of Nations World War I memorials Centenary outbreak Portal Weapons History Modern American Civil War World War I Chemical Germany Infantry World War II Germany France Italy Soviet Union United Kingdom United States Korean War Vietnam War Premodern Medieval European Types Aircraft Ancillary Anti-aircraft Anti-ballistic Anti-personnel Anti-tank Area denial Artillery Biological Chemical Ceremonial Combat vehicle Conventional Crew - served Cyber Deadly Directed - energy Explosive Firearm Hunting Improvised Incendiary Martial arts Mass destruction Melee Non-lethal Offensive Personal Pneumatic Practice Ranged Space Tectonic Torpedo Toy Other Arsenal Industry Mount Criminal possession Science fiction Retrieved from `` https://en.wikipedia.org/w/index.php?title=Chemical_weapons_in_World_War_I&oldid=842933863 '' Categories : Chemical warfare by conflict Environmental impact of war Military equipment of World War I World War I crimes World War I crimes by Imperial Germany World War I crimes by the British Empire and Commonwealth United Kingdom chemical weapons program Hidden categories : Articles with inconsistent citation formats CS1 : Julian -- Gregorian uncertainty CS1 maint : BOT : original - 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Question: when was chlorine gas first used in ww1
Answer: before 2 January 1915