Expert comment: what are Novichok agents?02 September 2020
Following the use of Novichok agents in 2018 and 2020 as a poison, experts from the University of Reading's School of Chemistry, Food and Pharmacy explain what Novichok agents are:
Professor Gary Stephens, a pharmacology expert at the University of Reading, said:
“This is a more dangerous and sophisticated agent than sarin or VX and is harder to identify. It causes a slowing of the heart and restriction of the airways, leading to death by asphyxiation.
“One of the main reasons these agents are developed is because their component parts are not on the banned list. It means the chemicals that are mixed to create it are much easier to deliver with no risk to the health of the courier.”
Professor Laurence Harwood, Professor of Organic Chemistry and Director of the Chemical Analysis Facility at the University of Reading said:
"Novichok" (It means "newcomer") refers to a family of structurally related nerve agents developed in Russia during the 80's and 90's - although Russia has consistently denied this.
"The Novichok agents are among the most lethal nerve agents known, being even more toxic than VX. Most are liquids but at least one can be prepared in powder form. They are "binary" nerve agents. This means that they are formed when needed by bringing together two much less toxic (and therefore less dangerous to the would-be assassin) and harder to detect, precursor molecules.
"Like many nerve agents, the Novichok agents are cholinesterase inhibitors - they block the enzyme that breaks down acetyl choline a chemical messenger produced in the synapse between neurons to allow passage of the nerve impulse from cell to cell. Normally, having done its job, the acetyl choline is destroyed in order not to keep firing the nerve impulse. If this does not happen, muscles continue to contract in an uncontrollable way. This can lead, among other things, to cardiac arrest or suffocation due to the lungs filling with fluid.
"Novichok agents can apparently last for several weeks or months in the environment as evidenced by the poisoning of Charlie Rowley and Dawn Sturgess in Salisbury, discovered unconscious in their home several months after the poisoning of Sergei and Yulia Skripals in March 2018.
"The common treatment for such nerve agent poisoning is to use atropine, which is itself highly toxic (it is an alkaloid produced by the deadly nightshade plant). Atropine causes muscles to relax by reactivating the cholinesterase enzyme (The name "belladonna" for the plant comes from the fact that women would put deadly nightshade extract into their eyes to make their pupils enlarge as the iris muscles relaxed). Normally atropine is administered with an ''oxime" that potentiates its activity. This treatment has its risks but is better than doing nothing.
"The Novichok agents contain fluorine and so detection of raised levels of fluoride or fluorine containing molecules from decomposition/metabolism products in the blood and urine, together with the symptoms will enable medics to give a pretty certain diagnosis."