Nerve agents have made many news headlines following the poisoning of Russian spy Sergei Skripal,66, and his 33-Year old daughter Yulia in Salisbury on the 4th March. Whilst there is no doubt this attack will have political implications for Russia’s relationship with the West there are still questions surrounding the short and long-term effects of nerve agents on the body, their previous use and the risk they pose to the public.
Nerve agents are chemicals usually liquid at room temperature with little or no smell that act on the central nervous system (the brain and the spinal cord) and peripheral nervous system(nerves and ganglia) disrupting nerve transmissions to organs. Exposure to nerve agents is most likely to occur through inhalation or exposure to eyes or upper respiratory tract tissue. The neurotransmitter acetylcholine stimulates muscles and is then broken down by the enzyme acetylcholinesterase. Some nerve agents stop acetylcholinesterase from breaking down acetylcholine causing excessive amounts of acetylcholine to build up at muscles resulting in muscle paralysis which can cause loss of movement resulting in death from respiratory failure.
Immediate effects to nerve agent exposure after high or intermediate level include:
Effects after 30 minutes of exposure include:
The long-term effects of exposure to nerve agents at a high and possibly intermediate-level can cause significant long-term neurological and neuropsychological outcomes that include delayed neuropathy. Neuropathy is defined as the disease or dysfunction of nerves which can result in weakness and numbness.
Nerve agents are considered a type of chemical warfare and banned in the Chemical Weapons Conventions in 1997 which banned the stockpiling, development and use of nerve agents. This was signed by Russia, USA and 163 other countries. They have previously been used in terrorist attacks in Japan in 1994 and 1995 where the nerve agent Sarin was released resulting in the deaths of 19 people and putting over 6,000 in the hospital.
After high or intermediate level exposure to a nerve agent an antidote must be administered as soon as possible. Antidotes to nerve agents include atropine and pralidoxime which work by clearing the nerve agent, reversing the amount of acetylcholine and reactivating the enzyme acetylcholinesterase. Additionally, drugs such as diazepam are often needed as well as artificial respiration and supportive therapy.
Personnel from the Defence Chemical Biological Radiological and Nuclear Centre at Porton Down in Wiltshire identified the nerve agent as Novichok.Novichok is a choline esterase inhibitor which effects are very rapid, believed to be 5-10 times more toxic than the nerve agent VX and very difficult to treat.
As well as Sergei Skripal and Yulia Skripal police officer Det Sgt Nick Bailey was also treated in hospital after exposure to the nerve agent but was released on the 22 March. A futher 48 people were assessed in hospital after the Salisbury attack and up to 500 people who went to the Mill pub or Zizzi restaurant in Salisbury on Sunday 4th March or Monday 5th have been told to wash their clothes and possessions. Futhermore 180 military personal have been sent to remove vehicles and objects that may have been contaminated.However Terrorism Police UK have urged that the threat to them is minimal and “the public should not be alarmed and the public health advice remains the same” and Chief Medical Officer Sally Davies has reassured the public that “health risk to the residents of Salisbury remains low”.
Following the incident, The UK have expelled 23 Russian diplomats. The European Council have supported this decision issuing a statement agreeing with the UK that it was “highly likely” that Russia was responsible for the attacks. Internationally 27 countries both in and outside Europe are set to expel Russian diplomats. Theresa May stated “This will be the single biggest expulsion for over thirty years and it reflects the fact that this is not the first time that the Russian State has acted against our country.” The UK claims that not only do they have evidence that Russia have violated the chemical weapons convention, but they have also been behind several other assassinations in the UK such as the murder of Alexander Litvinenko in 2006. Russia deny these allegations are set to expel over 60 diplomats from different countries and have issued 14 questions to the UK following the Salisbury attack.
Article by University of Birmingham intern Natasha Osborn Patel twitter.com/patelosborn