All the newspapers in the world report the news of the suspected poisoning of the Russian opposition leader Alexei Navalny with the nerve agent Novichok. What is it about?
Nerve agents (discovered through pesticide research) belong to a group of substances known as “organophosphorus”, or “OP” for short. There are thousands of OP substances, many of them can harm the body by inhibiting a family of enzymes known as “cholinesterases”, essential for regulating the activity of the central nervous system in animals.
OP pesticides are much less toxic to humans than nerve agents because they have been designed to specifically inhibit insect cholinesterases. Nerve agents, on the other hand, were created for human cholinesterases. Indeed, by interfering with the nervous system, Novichok and other “similar” ones can kill a person by asphyxiation or cardiac arrest. All types of nerve agent poisoning can be treated with standard antidotes such as atropine and diazepam.
For example, military antidotes are generally designed to allow survival from at least five lethal doses of a nerve agent. However, no antidote will be effective against a massive dose. Immediate decontamination is also known to be a highly effective practice against nerve agents and is the recommended initial treatment strategy for chemically contaminated victims in the UK and US.
In the case of Navalny, the politician appears to have been poisoned through a tainted cup of tea. Exact details of the incident are not available, but a variety of factors may have influenced the absorbed dose – presumably massive – but that wasn’t enough to kill him. Navalny, in fact, may have drunk only a few sips rather than the whole cup. Early reports also indicate that the man vomited. All of these factors may have contributed to lowering the lethal dose.
Fortunately, the Russian activist is now out of danger and breathing alone.