When the Germans unleashed clouds of toxic chlorine at Ypres in April 1915, the first large gas attack grabbed a lot of attention during WWI. At Ypres, the gas produced extensive panic and confusion among the British and Canadian forces, as well as widespread panic and confusion among the French colonial troops. International law currently prohibits the use and possession of chemical weapons. Despite a widespread prohibition on the use of chemical weapons and international attempts to eliminate existing stockpiles, numerous countries continue to pursue active chemical weapons programs. The blister agent utilized in the combat was sulfur mustard, more commonly known as mustard gas. Personnel were targeted and exposed to blister agents such as sulfur mustard or lewisite, resulting in casualties. Such weapons, which are delivered in liquid or vapour form, burn the skin, eyes, windpipe, and lungs.
