Mustard Gas

Mustard Gas

A profile of the chemical agent mustard gas.

Last updated May 28, 2008 8:00 am (EST)

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What is mustard gas?

A chemical agent that attacks the skin and eyes, mustard gas is one of the best known and most potent chemical weapons. It causes severe blisters and, if inhaled, can damage the lungs and other organs. It is usually disabling—sometimes gruesomely so—but not fatal. Unlike other chemical agents, mustard gas does not produce immediate effects; symptoms of exposure appear one to six hours later. This makes mustard gas especially insidious, as victims can suffer tissue damage before they even realize they need treatment. Mustard gas also attacks a cell’s DNA, increasing the risk of cancer and birth defects.

Does mustard gas have anything to do with mustard?

No. In some forms it is yellowish and reputedly smells like mustard, but its aroma has also been likened to the smell of horseradish, garlic, and apples. At room temperature, it’s actually a liquid rather than a gas, but the name “mustard gas” has stuck since it was used in notorious gas attacks during World War I.

How difficult is it to make mustard gas?

Making mustard gas is easier than making nerve gases but harder than “weaponizing” industrial chemicals such as chlorine, experts say. Without special equipment, an individual probably couldn’t make enough mustard gas to kill large numbers of people.

Have terrorists ever used mustard gas?

No. But there are unconfirmed reports that groups linked to Osama bin Laden’s al-Qaeda network tried to obtain the ingredients to make mustard gas in Afghan labs.

How does mustard gas compare with other deadly chemicals such as sarin and VX?

Mustard gas is a blister agent, which limits its appeal as a weapon because it is less likely to prove deadly than nerve agents like sarin and VX. But depending on the level of exposure, mustard gas can also leave victims with more lasting injuries. Dr. Jean Pascal Zanders of the Stockholm International Peace Research Institute (SIPRI) says that terrorists might consider using mustard gas to cause economic or social disruption—by contaminating a transportation route, for instance—but probably wouldn’t use it to cause mass casualties.

Has mustard gas been used against civilians?

Yes. Saddam Hussein used mustard gas on Kurds in northern Iraq during a 1987-88 campaign known as the Anfal. The worst attack occurred in March 1988 in the Kurdish villageof Halabja; a combination of chemical agents including mustard gas and sarin killed 5,000 people and left 65,000 others with severe skin and respiratory diseases, abnormal rates of cancer and birth defects, and a devastated environment. Experts say Saddam launched about 280 chemical attacks against the Kurds.

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Nonproliferation, Arms Control, and Disarmament


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