- Also called:
- sulfur mustard or dichlorodiethyl sulfide
- Related Topics:
- poison gas
- sulfide
- On the Web:
- National Center for Biotechnology Information - Sulfur Mustard (Nov. 01, 2026)
mustard gas
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What is mustard gas?
Mustard gas is a liquid agent used in chemical warfare that creates blisters on the skin and mucous membranes upon contact. It was first synthesized in 1860 by British chemist Frederick Guthrie.
The Germans introduced it as a chemical weapon in 1917 during World War I. Though the Geneva Gas Protocol of 1925 prohibited mustard gas and other chemical and biological weapons, it did not prevent countries from stockpiling the chemical. The Chemical Weapons Convention of 1993 placed mustard gas on the list of regulated agents. Derivatives of mustard gas are used in chemotherapy to treat cancer.
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Why is mustard gas considered dangerous?
Mustard gas is considered dangerous because it causes chemical burns on the skin and can have long-term health consequences. Symptoms often appear hours after exposure and include yellow blisters, itchiness, and redness. If the eyes are affected, pain, swelling, and potential blindness can occur. Inhaling mustard gas can burn and blister the respiratory system, leading to cough, shortness of breath, and potentially fatal damage. Long-term exposure can result in chronic respiratory disease and cancers.
Mustard gas was used as a chemical weapon starting in World War I. The Geneva Gas Protocol of 1925 prohibited mustard gas, but the agreement did not prevent countries from stockpiling the chemical. The Chemical Weapons Convention of 1993 placed mustard gas on a list of regulated agents.
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How does mustard gas affect the human body?
Mustard gas, a liquid agent dispersed as a mist, causes chemical burns on contact, leading to second and third-degree burns, with symptoms often delayed by hours. Exposure can cause yellow blisters, itchiness, and redness. Eye contact can result in irritation, pain, swelling, and potential blindness.
Inhaling mustard gas vapors burns and blisters the respiratory system, causing coughing and shortness of breath; acute exposure can be fatal, while prolonged exposure may lead to chronic respiratory disease and cancers. Mixing mustard gas with water creates hemi-mustard and hydrochloric acid, intensifying its hazardous effects on the skin.
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When and where was mustard gas first used?
Mustard gas was first used by the German army in 1917 during World War I. The site of its introduction as a chemical weapon was on the Western Front. Soon after, France and Great Britain also developed mustard gas capabilities. It was delivered using various methods, such as spraying from aircraft and deploying bombs, shells, and rockets, to incapacitate as many soldiers as possible. The use of mustard gas and other chemical and biological weapons was prohibited in 1925 by the Geneva Gas Protocol.
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What steps are taken today to prevent the use of mustard gas in warfare?
Mustard gas is banned as a chemical weapon under the Chemical Weapons Convention (CWC) of 1993. The treaty requires signatories to eliminate their stockpiles and sets up verification procedures to check compliance, including challenge inspections of undeclared sites.
Most countries have signed the treaty and have reduced or eliminated their chemical stockpiles. The United States launched the Cooperative Threat Reduction Program to help countries of the former Soviet Union demilitarize their chemical, biological, and nuclear facilities and arsenals.
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mustard gas, in chemical warfare, a liquid agent that blisters the skin and mucous membranes upon direct contact. It has a faint garlic or mustard odour. Despite its name, mustard gas is technically a liquid and forms a mist of small droplets in the air when released.
History
British chemist Frederick Guthrie is generally recognized as the scientist responsible for the synthesis of mustard gas, in 1860. While synthesizing the compound, he experienced some of its toxic effects.
Mustard gas was introduced as a chemical weapon by the Germans in 1917, during World War I. Soon after its introduction to the battlefield, France and Great Britain developed their own mustard gas capabilities. Mustard gas was delivered to the enemy using many methods, including being sprayed from aircraft and deployed in bombs, shells, and rockets, with the goal of incapacitating as many soldiers as possible. It is estimated that about 2β3 percent of soldiers exposed to mustard gas died, and many more were permanently removed from service.
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In 1925 the Geneva Gas Protocol was drafted, which called for the prohibition of mustard gas and other chemical and biological weapons. Although it was signed and ratified by many countries, the document failed to address the production, storage, and testing of the forbidden weapons, which allowed countries such as the Soviet Union and the United States to amass large supplies. In addition, several major powers (including the United Kingdom, France, and the Soviet Union) explicitly reserved the right to use the forbidden weapons for retaliatory purposes. However, the agreement did prevent further use of mustard gas in most western conflicts. Despite this, the weapon was used by Japan in China in World War II (Japan did not sign the Geneva Gas Protocol) and during the Iran-Iraq War (1980β1988).
Mustard gas was placed on the regulated agents list under schedule 1 of the Chemical Weapons Convention of 1993, which contains substances with very few uses other than as a weapon of mass destruction. Most countries signed this international treaty and have since reduced or completely eliminated their stockpiles of the chemical.
As a result of research conducted in the 1940s, chemicals derived from mustard gas, such as sulfur mustard and nitrogen mustard, were used in chemotherapy to treat cancer; several such chemotherapy medications are still in use, including mustargen, also known as mechlorethamine. Research for other medical uses of mustard compounds continued well into the 1970s.
Effects of mustard gas
Exposure to mustard gas is not usually fatal but can maim and have other long-term health consequences. It typically results in second and third degree chemical burns to the areas in contact with the gas. The onset of symptoms is often delayed by several hours, and those exposed to the gas may not initially be aware of the exposure. Common symptoms include yellow blisters on the exposed skin, often preceded by itchiness and redness. If the eyes were affected, eye irritation, with pain and swelling, may occur; excessive exposure to the eyes can lead to temporary or permanent blindness. Mustard gas is only slightly soluble in water, making it difficult to rinse off the skin after contact. In fact, when water combines with mustard gas it creates a chemical reaction and forms hemi-mustard and hydrochloric acid, both of which have their own hazardous effects on human skin.
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If vapours from mustard gas are inhaled, the chemical burns and blisters the lining of the respiratory system, resulting in cough and shortness of breath; significant acute exposure can be fatal. If initially survived, prolonged or heavy exposure can result in chronic respiratory disease and often leads to lung and respiratory cancers.