Novichok (A-Series)
Definition
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. A-234 was confirmed by OPCW Designated Laboratories in the 2018 Salisbury and 2020 Navalny poisonings.
- Chemical class
- Phosphoramidate nerve agents
- Named members
- A-230, A-232, A-234
- Reported toxicity
- Roughly five to ten times that of VX
- Confirmed cases
- Salisbury 2018 and Navalny 2020, both OPCW-confirmed
Common questions
How did the OPCW confirm A-234 in the Salisbury and Navalny cases?+
Designated OPCW reference laboratories independently analysed biomedical and environmental samples using validated analytical chemistry methods and matched the results against reference standards, then reported their findings to corroborate the identification made by national authorities.
Why do toxicity estimates for A-series agents vary between sources?+
Much of the primary data comes from a small number of animal studies and reconstructed historical Soviet research rather than a large, independently replicated body of published work, so reported potency multiples carry more uncertainty than figures for well-studied agents like VX.
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...
- 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)....
- VX
- 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...