vesicant sulfur mustard phosgene Germans chlorine
For example, there were an estimated 186,000 British chemical weapons casualties during the war (80% of which were the result of exposure to the vesicant sulfur mustard, introduced to the battlefield by the Germans in July 1917, which burns the skin at any point of contact and inflicts more severe lung damage than chlorine or phosgene), and up to one-third of American casualties were caused by them.