Malaysian police have revealed the substance that killed Kim Jong Nam was a highly toxic nerve agent that’s banned under a number of international conventions.
VX nerve gas was first developed in the UK in the 1950s as a deadly chemical warfare agent, and according to the Centers for Disease Control and Prevention (CDC).
Experts say the formula has been replicated in the past by the US, Russia, Syria and Iraq.
Here’s what we know:
What is it?
VX nerve agent is an oily liquid that’s amber in color, but it’s both odorless and tasteless.
Nerve agents, like VX, are the most toxic and deadly chemical warfare agents — they’re chemically similar to pesticides, although far stronger.
VX is the most potent of all nerve agents, including Sarin, which was developed in Germany in 1938 as a pesticide.
As a highly lethal chemical substance that can potentially kill large numbers of people, VX is considered a weapon of mass destruction.
How does it work?
VX, if in vapor form, is the quickest and deadliest form of the killer gas. As a liquid, it could potentially be released into a water supply or used to poison someone’s food.
Like all nerve agents, VX stops a vital enzyme from working — which eventually leads to the body tiring, and no longer being able to breathe.
VX is not only the deadliest nerve agent, but also the most persistent in the environment — it evaporates slowly, especially in cold conditions, making it both a long- and short-term threat.
What are the symptoms?
Depending on how much a person was exposed to, symptoms will start occurring either immediately or up to 18 hours later.
Large doses of the nerve gas can cause convulsions, loss of consciousness, paralysis and death, because of respiratory failure.
Smaller, non-fatal doses can cause a wide range of symptoms that include increased heart rate, blurred vision, nausea, diarrhea, drooling, pain and weakness.
Even just small doses of the gas can cause confusion and drowsiness.
There are antidotes for VX exposure available and they are most effective when administered immediately.
Is it banned?
As a chemical weapon, VX is banned under a number of international agreements including the 1925 Geneva Protocol and the 1993 Chemical Weapons Convention.
The 1925 Geneva Protocol came about after the use of poisonous gas in World War I, which was later extended by the 1993 Convention to include a ban on their development, production, stockpiling, retention and transfer of chemical weapons.
The Chemical Weapons Convention classifies VX as a Schedule 1 chemical, which means it poses a “high risk” to the convention and is rarely used for peaceful purposes.
Signatories are only permitted to keep Schedule 1 chemicals in small quantities for research, medical, pharmaceutical of defensive use, according to the Arms Control Association.
Both the US and Russia have in the past admitted to keeping stockpiles of VX, and under the Convention are obligated to destroy them.
Who has it?
VX nerve gas was first used during the Iran-Iraq war in the 1980s. It’s part of the same family of toxic substances as Sarin, which was used in the 1995 nerve gas attack on the Tokyo subway.
In the attack, members of the Aum Supreme Truth cult released Sarin nerve gas that killed 12 people and sickened more than 5,500 commuters.
VX is said to be relatively easy to produce in a reasonably sophisticated laboratory.
“Any country with a sophisticated chemical weapons effort can produce VX. The formula has been around since the 1950s so its nothing new it just has to be made, the political will and determination that we are going to build this weapon,” said CNN military analyst Rick Francona.