VX
Definition
O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate. A V-series nerve agent. Very low volatility, extreme skin-penetration toxicity. Developed by ICI (UK) in the 1950s. Used in the 2017 Kuala Lumpur assassination of Kim Jong-nam.
- Class
- V-series nerve agent
- Chemical name
- O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate
- Volatility
- Very low
- Route of concern
- Extreme skin-penetration toxicity
- Notable use
- 2017 Kuala Lumpur assassination of Kim Jong-nam
Common questions
Why is VX's low volatility significant for forensic and hazard response?+
Because it evaporates very slowly, VX persists on surfaces, clothing, and skin far longer than a volatile agent like sarin, so contamination can remain a hazard hours or days after exposure and residue can still be recovered for analysis long after the incident.
How is VX exposure typically confirmed in a forensic laboratory?+
Analysts look for the parent compound or its degradation products, such as EA-2192 and related hydrolysis markers, in blood, urine, or environmental swabs using techniques like GC-MS or LC-MS, and for depressed blood cholinesterase activity as a biological indicator of nerve agent exposure.
Related terms
- 31P NMR
- Phosphorus-31 nuclear magnetic resonance spectroscopy, used to confirm the presence of phosphorus-containing OP nerve agents and their degradation products. Diagnostic: chemical shift...
- AChE (Acetylcholinesterase)
- The enzyme that terminates cholinergic nerve impulses by hydrolysing acetylcholine. Irreversibly phosphorylated at Ser203 by OP nerve agents, causing accumulation of acetylcholine...
- IMPA (Isopropyl Methylphosphonic Acid)
- The primary hydrolysis product of sarin (GB). Detected in urine of sarin-exposed individuals and in environmental matrices by GC-MS and LC-MS/MS. The...
- Novichok (A-Series)
- A class of Soviet-era phosphoramidate nerve agents (A-230, A-232, A-234) from the Foliant programme. Reported to be 5-10x more toxic than VX....
- OCAD (OPCW Central Analytical Database)
- The OPCW's reference library of confirmed GC-MS and NMR spectra for all scheduled chemicals and their degradation products, used by Designated Laboratories...
- OPCW Designated Laboratory
- A laboratory authorised by the Organisation for the Prohibition of Chemical Weapons to conduct official CWC verification analysis. Must pass biennial proficiency...
- Sarin (GB)
- Isopropyl methylphosphonofluoridate, a G-series nerve agent. Highly volatile, AChE inhibitor. LCt50 ~35 mg.min/m3 by inhalation. Key degradation products: IMPA (isopropyl methylphosphonic acid)...
- Schedule 1 (CWC)
- The list of chemicals with little or no commercial use outside chemical weapons under the Chemical Weapons Convention. Includes all nerve agents...
- Sulphur Mustard (HD)
- Bis(2-chloroethyl) sulphide. The prototype vesicant (blister agent). Alkylates DNA and proteins via an ethylene sulfonium ion intermediate. First used at Ypres (1917)....