Soman or GD (O-Pinacolyl methylphosphonofluoridate) is an extrememly toxic substance that is one of the world's most dangerous weapons of war. Because it fatally interferes with normal functioning of the mammalian nervous system, it is classified as a nerve agent. As a chemical weapon, it is classified as a weapon of mass destruction by the United Nations according to UN Resolution 687, and its production and stockpiling was outlawed by the Chemical Weapons Convention of 1993. Soman was the third of the so-called G-series nerve agents discovered (along with GA (tabun), GB (sarin), and GF (cyclosarin)).
It is a volatile, corrosive and colourless liquid with a faint odour when pure, more commonly it is a yellow to brown color and has a stronger odour described as camphor. The LCt50 for Soman is 70 mg-min/m3 in humans. It is both more lethal and more persistent than sarin or tabun, but less than cyclosarin.
GD can be thickened for use as a chemical spray using an acryloid copolymer. It can also be deployed as a binary chemical weapon; its precursor chemicals are methylphosphonyl difluoride and a mixture of pinacolyl alcohol and an amine.
Alternative names
Soman is occasionally referred to names other than soman or GD:
- Phosphonofluoridic acid, methyl-, 1, 2, 2-trimethylpropyl ester
- Pinacolyl methylphosphonofluoridate
- 1,2,2-Trimethylpropyl methylphosphonofluoridate
- Methylpinacolyloxyfluorophosphine oxide
- Pinacolyloxymethylphosphonyl flouride
- Pinacolyl methanefluorophosphonate
- Methylfluoropinacolylphosphonate
- Fluoromethylpinacolyloxyphosphine Oxide
- Methylpinacolyloxyphosphonyl flouride
- Pinacolyl methylfluorophosphonate
- 1,2,2,-Trimethylpropoxyfluoromethylphosphine oxide
History
Soman was discovered by Richard Kuhn in Germany in 1944, and represented the last wartime nerve agent discovery (GF was not found until 1949.) Soman was given the identifier GD post-war (GC was already in medical use) when the information relating to Soman was recovered by the Soviet Union from its hiding place in a mine.
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