The Chemist’s War

Chemists War

Whether made at home from plastic water bottles or of hi-spec military grade, gas masks are today as symbolic an image of conflict as they were in WW1 when chemicals, used to irritate, immobilise and even kill, first became a major component of warfare.

Germany employed up to 2,000 chemists and generally remained well ahead in the development of offensive gases; it took the Allies six months to formulate their own phosgene weapons, and one year to develop their own mustard gas.

Their use violated both the 1899 Hague Declaration Concerning Asphyxiating Gases and the 1907 Hague Convention on Land Warfare. Nevertheless, chemical weapons were deployed by all major belligerents in what is often referred to as ‘The Chemist’s War’, constituting a war crime that is estimated to have caused around 1.3 million casualties.

These noxious gasses affected not just those on the battlefield, but also the chemical workers involved in their manufacture on the home front and had significant effect on public health services in the years to follow. The psychological effect of chemicals is visible even in the aftermath of war, inspiring post-war art such as John Singer Sargent’s painting “Gassed”. Let’s have a look at some of the chemical agents used:

Tear Gas

Used by the French army in August 1914 against the Germans,  this was the first chemical attack in World War One. This was used to irritate, causing streaming eyes, rather than as a disabling or fatal attack. The German’s were outraged, and felt that Germany was now free to use poison gas.


Introduced at Ypres on 22nd April 1915, chlorine attacks caught the world by surprise. A potent irritant, chlorine can cause damage to the nose, eyes, throat and lungs with high concentrations causing a painful death by asphyxiation. Though devastating in the trenches, it’s grey-green colour was easy to detect, and simple tricks such as covering the mouth with a damp cloth helped to limit the damage – some men even dipped their cloths in urine as this neutralized the effect of the gas.

Women at home were encouraged to create pads for this purpose and by 1915 the British Army was equipped with a full helmet, complete with pad respirator, diminishing the effectiveness of chlorine gas attacks.


First used by France in 1915, phosgene is colourless, making it hard to detect, and required a low concentration to cause death. It could be used alone, or combined with chlorine. Nicknamed the white star due to the markings on the shells, phosgene was deadly but slow. Symptoms took up to 24 hours to take hold, meaning the enemy could still fight, though they would be incapacitated within hours.  The British gas helmet was adapted against phosgene in January 1916.

Mustard Gas

Showcased at the Third Battle of Ypres by the Germans in 1917, mustard gas was the most widely used. Used to disable the enemy, heavy mustard gas settled on the ground (devastating in the trenches), remaining for days or even weeks depending on the weather.

Causing blistering eyes, vomiting, internal and external bleeding, mustard gas attacked the lungs, and could take weeks to kill. Some soldiers didn’t even realize they had been gassed as symptoms could be slow to develop. Not suitable for attacks, mustard gas was used to harass and weaken the enemy without exposing assaulting infantry to the devastating effects.


Unprepared for the introduction of poison gas as a weapon, early and attempts to counteract their effects included such desperate plans as to deploy 100,000 fans to disperse the gas and a proposal to equip front-line sentries with diving helmets fed by extra long hoses. But, as with many inventions in pressurised situations, the evolution of an effective countermeasure began with a simple response to chlorine gas: urinating on a piece of cloth which was then held over the nose.

By the end of the war, the lethal effects of gas had largely mitigated. Nevertheless, their effects were traumatic, as they still are when things like tear gas are used by armies and police forces against protesters and civilians today.



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Written by Sarah Ashbridge

Office monkey by day, forensic archaeologist by night, Sarah Ashbridge is a jack-of-all-trades and the master of one: the forensic identification the War Dead. She trained originally as an Egyptologist, but interests in the history of death and burial saw her make the step into archaeology, completing an MSc in Forensic Archaeology and Crime Scene Investigation at the University of Bradford. Armed with an ever-increasing library of books, a handful of illustration pens and a brand new trowel, Sarah writes our regular #WWWednesday column, working towards her PhD in Forensic Archaeology.

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