VX: The Nerve Agent Used To Kill Kim Jong Nam Is Rare And Deadly

Feb 24, 2017
Originally published on April 7, 2017 5:42 am

When the half-brother of North Korean leader Kim Jong Un collapsed at a Malaysian airport last week, poisoning was instantly suspected. But on Friday, Malaysian authorities revealed that an autopsy had turned up not just any poison, but a rare nerve agent known as VX.

VX is among the deadliest chemical weapons ever devised. A colorless, odorless liquid, similar in consistency to motor oil, it kills in tiny quantities that can be absorbed through the skin. A relative of the nerve agent Sarin, VX disrupts communications between nerves and muscles. Victims of VX initially experience nausea and dizziness. Without an antidote, the chemical eventually paralyzes the diaphragm, causing suffocation.

That may have been the fate of Kim Jong Nam, the estranged half-brother of North Korea's leader. Security footage showed that Kim was approached by two women who appeared to cover his face with a cloth. Moments later, he fell ill and sought help. He died before reaching a hospital.

If the Malaysian analysis is correct and VX was the culprit, that would seem to suggest that the North Korean state itself is behind the killing.

"Hardly anybody has it," says Dan Kaszeta, a chemical weapons expert and consultant based in London. The U.S. has destroyed nearly all of its stocks of VX in recent years.

North Korea is among the few states in the world that have an active chemical weapons program. It is not a signatory to the Chemical Weapons Convention, which bans the use of such weapons. The South Korean government estimates that Pyongyang has somewhere between 2,500 to 5,000 tons of various agents in its arsenal. That likely includes VX, says Joseph Bermudez, an analyst with the website 38 North who has looked at North Korea's program in depth.

Kaszeta, who was once an officer in the U.S. Army Chemical Corps, says VX and agents like it are designed for long-term contamination of a battlefield. Once VX is spread over equipment or facilities, it stays there for long periods of time. Before it was banned, countries such as the U.S. and Russia stockpiled VX in large quantities with the intention of rendering strategic targets, like ports, useless.

But its lethality and stability could also make it a good tool for assassination, Kaszeta says. A tiny quantity could be sealed in a glass container with no ill effects, and it wouldn't be readily detectable by authorities. Because VX does not evaporate easily, it would not contaminate the surrounding air. That might explain why no one else at the Malaysian airport appears to have fallen ill.

It remains unclear whether the Malaysian authorities will seek to verify their VX detection with official bodies like the Organization for the Prohibition of Chemical Weapons.

"OPCW stands ready to provide its expertise and technical assistance, if required, to any State Party to the Chemical Weapons Convention," the agency said in a statement.

North Korea's official news agency has denied the country had any role in the death. It has blamed Malaysia for fabricating evidence of a murder at the behest of South Korea.

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There are fresh twists today in the apparent assassination of the half-brother of North Korea's leader, Kim Jong Un. The brother, Kim Jong Nam, died last week at an airport in Malaysia. Security footage showed that two women poisoned him. Now today, Malaysian authorities revealed it wasn't just any poison but a chemical weapon known as VX.

Joining me to discuss what to make of this is NPR science editor Geoff Brumfiel. Hey there, Geoff.


CORNISH: So start just by telling me, what is VX?

BRUMFIEL: Well, VX is a colorless, odorless liquid. It's about the consistency of motor oil, and it is extremely deadly. Less than a drop of this stuff on your skin - it'll absorb straight through, and within minutes, you'll start to feel headaches, nausea, tightness in the chest. What it actually does is it disrupts signals between nerves and muscles. That ultimately leads to the paralysis in the muscles you use to breathe and you suffocate. It's a nasty way to go.

CORNISH: How could you use something like that in an airport and have no one else be harmed?

BRUMFIEL: Well, this is the interesting thing about VX. It's a chemical weapon, and when you disperse it, you can hurt a lot of people. But in its liquid form, it's actually kind of safe, I guess you could say. That's because it's very stable. It doesn't sort of off-gas, so no one nearby can be exposed to it. And you can seal it in a bottle and transport it around, take it through airport security. It's very unlikely to go detected. So in a way, it's sort of the perfect weapon for assassinating a single person when it's used in a particular way.

CORNISH: Now, does the use of VX tell us anything about whether North Korea specifically was involved?

BRUMFIEL: Yeah because this is not just any poison. This is a chemical weapon that has been banned under the Chemical Weapons Convention. And most countries, you know, have vowed never to use it. North Korea is one of the few countries that hasn't signed up to the Chemical Weapons Convention. It's believed to have lots of chemical weapons, including VX. So if this use of VX is verified, that would kind of point the finger at the North Korean state in particular as a suspect in this crime.

CORNISH: In the meantime, what more have we learned about why North Korea would want Kim Jong Nam dead?

BRUMFIEL: This is a real mystery. There's not much evidence that this Kim brother was a particular threat. He lived most of his life outside of North Korea. He was a bit of a playboy. Now, there is a theory that China wanting Kim Jong Nam around in case something happened to Kim Jong Un, the current leader of North Korea, the idea being that Kim Jong Nam is part of the dynasty that has ruled North Korea and could be brought in if something happened or to prevent the collapse of the regime.

Kim Jong Un may not have liked that idea and may have wanted to try and head it off by getting rid of his half-brother. Certainly Kim Jong Un has assassinated political rivals within North Korea. We know he's capable of it.

CORNISH: You know, we hear so much about North Korea whenever it tests a missile obviously or a nuclear weapon. Is there any connection between those stories and what happened in Malaysia?

BRUMFIEL: I think there is a way to think about these things all together. I think it's important not to take one's eye off the ball here. I mean the real threat here is North Korea's missile and nuclear program. They have been developing very rapidly. You know, North Korea now has ballistic missiles that pose a significant threat to some of the U.S.'s allies in the region. It's thought that soon they'll have an intercontinental ballistic missile that could reach anywhere inside the continental United States.

And so I think it's important to understand that what we're looking at here is a regime that is increasingly isolated, that is, you know, doing all sorts of things that are on the fringe of what the global community considers acceptable. And it's a dangerous situation.

CORNISH: That's NPR's science editor Geoff Brumfiel. Geoff, thanks so much.

BRUMFIEL: Thank you. Transcript provided by NPR, Copyright NPR.