Characteristics of Nerve Agents

There are three types of nerve agents currently stored in chemical stockpiles in the United States VX, GB and GA. All three nerve agents are members of the organophosphate family. Nerve agent VX, a clear, odorless and tasteless liquid, has an appearance similar to motor oil. VX can become an aerosol very small droplets through explosion or a vapor through ignition. It is heavier than water and evaporates 2,000 times more slowly. Highly toxic in its liquid, aerosol and vapor forms, VX is the most hazardous when absorbed through the skin. As a vapor or aerosol, it can be inhaled and absorbed through the lungs or through the digestive system if eaten or swallowed. Nerve agent GB, also known as sarin, is one of the most toxic members of the organophosphate family. Under normal conditions, it is a clear to straw-colored liquid and has approximately the same density and evaporation rate as water. GB presents the greatest hazard when released in vapor form. Such vapors can be released only by evaporation of the liquid or vaporization into the air. Nerve agent GA, also known as tabun, is a colorless liquid with a slightly fruity odor. The agent inhibits nerve conduction very rapidly, within a matter of seconds or minutes.