VX

Structure and properties

VX (C11H26NO2PS, Mr = 267.4 g/mol) belongs to the group of organophosphates. It exists at room temperature as a slightly yellowish, oily, odorless and tasteless liquid with a high viscosity. The “V” stands for venom. The boiling point is relatively high at about 300°C. Therefore, VX is usually used as a liquid, as an aerosol, and less frequently as a gas. The neurotoxin was first synthesized in the 1950s as part of the development of insecticides in Great Britain. Related organophosphates are also used today as insecticides.

Effects

VX is an extremely potent neurotoxin. Its effects are due to irreversible inhibition of the enzyme acetylcholinesterase, which is responsible for the breakdown of the neurotransmitter acetylcholine to choline and acetate. This enhances the effects of acetylcholine by overstimulating nicotinic and muscarinic acetylcholine receptors. This results in involuntary muscle contractions, convulsions, loss of consciousness, coma, paralysis, hypotension, cyanosis, and death from cardiovascular and respiratory failure, among other effects. VX can be absorbed into the body through the skin, eyes, digestive tract and respiratory tract. It is also passed through contaminated clothing or objects and remains active for a long time.

Drug prevention and treatment

The following groups of drugs are used as antidotes:

The Swiss Army uses the ComboPen auto-injector with atropine and obidoxime chloride for acute treatment and pyridostigmine tablets for drug prevention.

Abuse

VX can be misused as a liquid or aerolized nerve agent in military or terrorist attacks and as a chemical weapon of mass destruction. It has also been used as a poison for assassinations. The most famous case is the murder of Kim Jong-nam, the eldest son of Kim Jong-il, the former dictator of North Korea. He was poisoned with VX at Kuala Lumpur Airport in Malaysia on Feb. 13, 2017. The so-called Aum cult also used homemade VX for assassinations in Japan in the 1990s.

Dosage

VX is extremely toxic and has a lethal effect even in the smallest amounts in the range of a few milligrams.