A Brief Introduction to Nerve Agents

In security policy, nerve agents are a relevant threat in chemical warfare, but also for attacks on individuals. The aim of this introduction is to provide basic historical, legal, medical and chemical knowledge of this complex matter for everyone who is interested in security policy and chemical warfare and to increase awareness. In the previous decade, attacks with the nerve agents sarin, VX and Novichok were reported. The weaponized nerve agents belong to the chemical group of organophosphates with four generations which block the enzyme acetylcholinesterase leading to a large variety of symptoms: The G-series, the V-series, the A-series (Novichoks) and the carbamates which are however currently not weaponized. The first chapter explains the mode of action and biochemical properties, then the history and the legal framework of the Chemical Weapons Convention. Thereafter, the symptoms and countermeasures are presented. The course of the resulting disease depends on the type of agent, the extent of exposure and the speed of therapeutic intervention. Rapid diagnosis and treatment are needed to limit damage and to prevent death, but also due to a chemical ‘aging’ process of the affected enzyme. The medical treatment of nerve agents is embedded into other measures like physical protection, decontamination and triage and includes the imminent pre-hospital and the hospital treatment phases. The treatment is based on anticholinergics (atropine), acetylcholinesterase reactivation by oximes, anticonvulsive therapy with benzodiazepines and respiratory support to prevent respiratory failure as primary cause of death. New therapeutic concepts like bioscavengers are briefly discussed and summarized