Mustard gas is a potentially lethal chemical warfare agent. More specifically, the term 'mustard gas' refers to several manufactured chemicals, including sulphur mustard and sesqui mustard. However, sulphur mustard is the only one to have been used in chemical warfare.

Although it is labelled as a gas, at room temperature sulphur mustard is really a liquid. It is denser than air, and oily in appearance. It can be colourless, dark brown, or somewhere in between. It can be odourless or smell something like mustard or rotten onions. As you can see, the name 'mustard gas' derived from its smell.

It was developed by the Germans in 1917 for use in World War I. The gas had many advantages and was considered to be the most effective chemical weapon of WW1. Being often odourless, it was hard for anyone to detect until hours had passed and symptoms finally started to occur. Mustard gas could also penetrate through clothing, leather and wood. It was also easy to deliver and when weather conditions were suitable, mustard gas could form a fog so as to limit the enemy's mobility.

The eyes are the part of the body most at risk when exposed to mustard gas. After exposure, it may take a few hours for any injury to become evident; the greater the exposure, the shorter the delay. People who experience minor exposure to the gas will find their eyes become irritated and swell up. More severe exposure can result in the eyelids burning and a sensitivity to light. Sometimes blindness follows as the cornea decays.

The next most likely area of the body to be affected by mustard gas is the respiratory tract. If the gas is inhaled, injuries can be quite serious and if not life-threatening, they are almost certain to plague a victim for the rest of their life. Minor exposure will result in the victim finding an unsuppressable urge to cough and experience an irritated throat. Breathing difficulties begin and swallowing becomes difficult. Following this, the throat becomes congested, making it even harder to breathe. More serious damage includes parts of the lung dying off, an even further tightening of the throat and pneumonia. Mucous, dead tissue and blood will usually block the airways and suffocate the victim. If someone survived these symptoms they would be sure to have weak lungs for the rest of their life.

The moister the area of the body, the more damage mustard gas does. Skin will blister, usually around the face, armpits and other area's where people tend to perspire. Once again, the higher the level of exposure, the worse the damage becomes. Blisters can start appearing anywhere between a few hours and a few days after initial contact. People have gotten away with minor itching of the skin. More serious cases involve large, gangrenous blisters. When mustard gas in its liquid form is placed on the skin, 80% will evapourate, 10% becomes fixed onto the skin and 10% is absorbed into the body.

Mustard gas was first used in Ypres, France, (that is how it received its alternate name of Yperite) on the 12th of July in 1917. It was later believed to have been used during the Italian - Ethiopian conflict in 1936, the Sino - Japanese conflict during World War II and in more recent times, the Iraqi - Iranian conflict during 1984-1986. From what information I could find, America used to manufacture the gas for research purposes until 1997, when it was ordered to destroy it. Iraq has also manufactured mustard gas in the past and continues to do it in the present, having given production figues of both 3080 tonnes and 2850 tonnes. In relation to other deadly chemical weapons like VX and sarin, mustard gas is not extremely effective in killing large amounts of people. Nevertheless, it does create numerous lasting, lifelong injuries.

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