Blister Agents: Lewisite (L), Mustard-Lewisite Mixture (HL)

CAS ID#: 541-25-3

Affected Organ Systems: None

Cancer Classification:  Please contact NTP, IARC, or EPA with questions on cancer and cancer classification.

Chemical Classification: Warfare and Terrorism Agents (used in acts of war or terror)

Summary: Lewisite is an oily, colorless liquid with an odor like geraniums. Mustard-Lewisite Mixture is a liquid with a garlic-like odor. Mustard-Lewisite is a mixture of Lewisite and a sulfur mustard known as HD. Lewisite might have been used as a chemical weapon by Japan against Chinese forces in the 1930s, but such reports have not been confirmed. Any stored Lewisite in the United States must be destroyed before April 2007, as mandated by the Chemical Weapons Convention.