Iranian chemical weapon victim exposed to Iraqi mustard gas during the Iran-Iraq war, breathes through a respirator. Tens of thousands of Iranians were exposed to Iraqi gas attacks.

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Mustard Gas After World War I

Mustard gas has seen action in other parts of the world since its introduction in World War I. The Japanese used mustard gas against the Chinese during World War II, while the United Nations accused Saddam Hussein of using the deadly gas against the city of Halabja in 1988 during the Iran-Iraq war to kill approximately 3,200 to 5,000 civilians [source: Blister Agent HD, The Nation]

According to CNN, troops in the Gulf War may have dealt with mustard gas on several occasions. As many as seven U.S. Army divisions, or approximately 100,000 soldiers, may have been exposed during the war. While the total number remains unconfirmed, several soldiers who served during the Gulf War experienced symptoms in line with mustard gas exposure [source: CNN].

At the end of the Gulf War, the U.N. imposed strict sanctions against Iraq in order to eliminate the risk of future chemical warfare. In addition, the U.N. adopted the Chemical Weapons Convention, a global treaty that prohibits the use of chemical weapons. The only countries that hadn't signed the treaty as of 2007 were Angola, Egypt, Lebanon, North Korea, Somalia, Syria and Iraq [source: Encyclopaedia Britannica]. As long as chemical weapons exist, they will forever be a threat. We can only hope they don't fall into the wrong hands.

For more information on chemical agents and warfare, visit the links on the next page.