VX most potent of all nerve agents - CDC

Compared with the nerve agent sarin, also known as GB, VX is considered to be much more toxic by entry through the skin and somewhat more toxic by inhalation.

This is according to information gleaned from the website of the Center for Disease Control and Prevention (CDC), one of the major operating components of the United States Department of Health and Human Services.

"The extent of poisoning caused by VX depends on how much VX a person was exposed to, how the person was exposed, and the length of time of the exposure," it said.

Inspector-General of Police Tan Sri Khalid Abu Bakar today revealed that VX was found following preliminary analysis of dry swabs of the eye mucus and face taken in the course of police investigation into the killing.

He said the presence of the substance, a chemical weapon, was stated in the preliminary report received by police from the Chemistry Department.

The CDC said it was possible that any visible VX liquid contact on the skin, unless washed off immediately, would be lethal.

"All the nerve agents cause their toxic effects by preventing the proper operation of an enzyme that acts as the body's 'off switch' for glands and muscles.

"Without an 'off switch', the glands and muscles are constantly being stimulated. They may tire and no longer be able to sustain breathing function," it said.

VX can last for days on objects that it has come in contact with. Under very cold conditions, VX can last for months.

"Because it evaporates so slowly, VX can be a long-term threat as well as a short-term threat. Surfaces contaminated with VX should therefore be considered a long-term hazard," the CDC said.

Jong-nam was at the KL International Airport 2 (klia2) on Feb 13 to board a flight to Macau when two women suddenly appeared before him and wiped his face with the palms of their hands which contained a poisonous liquid.

Jong-nam sought help at a customer service counter at the airport and was rushed to the Putrajaya Hospital but died on the way.