Synopsis

 

• Sulfur mustard, also known as mustard gas, HD, yellow cross, and yperite, was named for its mustard-like odor and taste and its yellow-to-dark brown color. (Note: It can also have an onion or garlic odor and taste.) There is no antidote for mustard gas.
• The freezing point for mustard is 57°F (13.9°C). This freezing point can be lowered if it is mixed with another agent such as lewisite. Mustard is not very volatile and relies on heat to be vaporized. However, release would probably be as an aerosol or droplets, making vaporization unnecessary. The LD50* of mustard is 100 mg/kg. This amount would be about 1-1.5 teaspoons for an average adult or enough to cover 25%-50% of the total body surface.

• Lewisite, also known as L, is an arsenical. Lewisite is a colorless, oily liquid in its pure form that may smell like geraniums, and it has an amber-to-black color in less pure forms. Dimercaprol (British anti-lewisite) is a chelating antidote and should be administered as soon as possible after exposure.
• Vesication from percutaneous exposure is caused by 14 μg of liquid lewisite. The blister fluid is not harmful, but it does contain arsenic. Lewisite's LCt50** by inhalation is 1500 mg × min/m3.

• There is little documentation regarding the effects of phosgene oxime, also known as CX, on humans. Although it is frequently classified as a vesicant, it does not produce blisters. Instead it is really an urticant, producing skin wheals similar to a nettle sting. There is no antidote for phosgene oxime.
• Phosgene oxime is a colorless, crystalline solid or, more typically, a yellow to brown liquid that can penetrate clothing and rubber. Phosgene oxime can be mixed with nerve agents to promote faster absorption of the nerve agent.
• LCt50** by inhalation is 1500-2000 mg × min/m3, and the LD50* for skin exposure is about 25 mg/kg.