What Is Mustard Gas?
CDC says sulfur mustard, known as mustard gas, mustard agent or by the military designation H or HD, is a human-made chemical warfare agent that blisters the skin and mucous membranes on contact, a type of agent called a vesicant or blistering agent. It is an oily liquid at room temperature that is clear to yellow or brown and smells like garlic, onions or mustard, or has no smell. ATSDR says it was made in large amounts during World Wars I and II and was reportedly used in the Iran-Iraq war of 1980 to 1988.
Symptoms are often delayed. CDC says signs and symptoms usually do not occur immediately and may take up to 24 hours to appear, and include eye irritation, swelling, pain, tearing and temporary blindness, difficulty breathing, cough, shortness of breath, wheezing and hoarseness, and skin blistering, itching, pain and redness. It says exposure usually does not cause death, noting that its use in World War 1 killed fewer than 5 percent of the people who were exposed and got medical care.
CDC advises getting clean by taking off all clothes, jewelry and accessories, blotting any liquid and showering, ideally immediately or as soon as possible. It says no known cure exists, and that treatment involves removing sulfur mustard from the body as soon as possible and providing supportive medical care.
CDC says long-term effects of skin exposure can include second- and third-degree burns, scarring, pigment changes and skin cancer, and that breathing it in can cause loss of taste and smell, chronic respiratory disease, repeated respiratory infections and respiratory cancers. ATSDR says the US Department of Health and Human Services and the International Agency for Research on Cancer have determined sulfur mustard is carcinogenic to humans. For disability compensation, the Department of Veterans Affairs recognizes exposure during field or chamber testing, World War I battlefield conditions, the German air raid on the harbor of Bari, Italy in World War II, and manufacturing and handling of blistering agents during military service.
Sources checked September 15, 2026. Every point below links the page it came from.
The sources behind this answer
- Medical referenceCDC says sulfur mustard is a human-made chemical warfare agent that blisters the skin and mucous membranes on contact, a type called a vesicant or blistering agent. CDC ↗
- Medical referenceCDC says sulfur mustard, known as mustard gas or by the military designation H or HD, is an oily liquid at room temperature that may smell like garlic, onions or mustard. CDC ↗
- Government sourceCDC says signs and symptoms of sulfur mustard exposure usually do not occur immediately, and some may take up to 24 hours to appear. CDC ↗
- Government sourceCDC lists eye irritation and temporary blindness, difficulty breathing, cough and hoarseness, and skin blistering, itching and redness among signs of sulfur mustard exposure. CDC ↗
- Government sourceCDC advises getting clean after sulfur mustard exposure by removing all clothes, jewelry and accessories, blotting any liquid and showering as soon as possible. CDC ↗
- Government sourceCDC says no known cure exists for sulfur mustard exposure, and treatment involves removing it from the body as soon as possible and supportive medical care. CDC ↗
- Government sourceCDC says long-term effects of sulfur mustard can include burns, scarring and skin cancer from skin exposure, and chronic respiratory disease and respiratory cancers from breathing it in. CDC ↗
- Government sourceCDC says sulfur mustard exposure usually does not cause death, and its use in World War 1 killed fewer than 5 percent of people who were exposed and got medical care. CDC ↗
- Government sourceATSDR says HHS and the International Agency for Research on Cancer have determined sulfur mustard is carcinogenic to humans, and it may cause respiratory cancer. ATSDR, CDC ↗
- Medical referenceATSDR says sulfur mustard was made in large amounts during World Wars I and II and was reportedly used in the Iran-Iraq war of 1980 to 1988. ATSDR, CDC ↗
- Regulatory filingFor disability compensation, the VA recognizes mustard gas exposure during field or chamber testing, World War I battle, the Bari harbor air raid in World War II, and blistering agent manufacturing. US Department of Veterans Affairs ↗
Sources checked September 15, 2026. A brand statement is the company’s own claim, which we report but have not verified. Our grades are model-based estimates, not lab tests.