All it takes is 10 milligrams to kill you — which is why VX has been banned around the world.
According to preliminary reports from Malaysian authorities, VX — aka O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate) — was likely the chemical used to kill Kim Jong-un’s half brother, Kim Jong-Nam, in an attack earlier this month. Investigators reportedly found traces of VX on Jong-Nam’s face and near his eyes.
Where did VX come from? Here’s the low down:
A Pesticide Gone Very Wrong
VX was discovered in 1952 by a pair of chemists in England investigating a class of organophosphate compounds. The team realized that VX was a potent pesticide, but before long, it became clear that it was really good a killing humans too. Research on the chemical and others like it ended in 1955. Yet, the potential to use VX as a chemical weapon did not go unnoticed by the British Armed Forces, who developed the class of organophosphate pesticides, along with the U.S. military, for chemical warfare.
There are not many known instances of VX being used on humans. One of the few attacks occurred in Japan when it was used by a doomsday cult for an assassination in 1994. VX may have also been used in the Iran-Iraq War in the 1980s.
Why VX is Lethal
VX is a tasteless, odorless, amber-colored liquid that according to the Centers For Disease Control and Prevention, evaporates “about as slowly as motor oil.” VX can be absorbed through the skin and is more potent than sarin.
The chemical does its dirty work by stopping your body’s ability to use an enzyme called acetylcholinesterase to break down a neurotransmitter called acetylcholine. As a result, your body makes too much acetylcholine, which then poisons you.
Within seconds of exposure, a person can start to feel symptoms. One tiny drop can cause sweating and muscle twitching. At lethal doses, you’re likely to seize, pass out and stop breathing.
The only way to reverse the effects is to administer an antidote — atropine sulfate — until the patient can breathe again (although in cases where a patient has recovered from VX poisoning, they have tended to suffer from life-long symptoms including headaches and muscle spasms). Doctors also have to use anticonvulsants to stop the seizing and a drug called 2-pralidoxine chloride to help the body break down acetylcholine again.
Who Has It
Although it is not particularly difficult to make, VX is so dangerous to handle, the Council on Foreign Relations, assumes terrorists won’t want to deal with it. Most countries don’t have VX on hand and it requires an expensive lab and corrosive chemicals to make it.
The U.S. made VX at its Newport Chemical Depot in 1961 and then agreed to destroy its stockpile. Starting in 1969, the U.S. began getting rid of the chemical by incineration, chemical neutralization, or sinking ships filled with it into the middle of the ocean.
Russia, Syria and North Korea are suspected of possessing a stash of VX.
Officials in North Korea have denied the country’s involvement in the murder of Jong-Nam and questioned how the two female suspects accused of wiping VX on his face would have survived coming into contact with the chemical themselves.