What is VX?

VX is a human-made chemical warfare agent classified as a nerve agent. Nerve agents are the most toxic and rapidly acting of the known chemical warfare agents. They are similar to insecticides called organophosphate insecticides in terms of how they work and what kinds of harmful effects they cause. However, nerve agents are much more potent than insecticides.

VX was originally developed in the United Kingdom in 1952 by scientists who were searching for a replacement for the insecticide DDT. VX is odorless and tasteless. VX is an oily liquid that is amber in color and very slow to evaporate. It evaporates about as slowly as motor oil.

Mild or moderately exposed people usually recover completely. Severely exposed people are not likely to survive.

Recovery from VX exposure is possible with treatment, but the antidotes available must be used quickly to be effective. Therefore, the best thing to do is avoid exposure. If exposure cannot be avoided, rapidly decontaminate and get medical care as quickly as possible. Leave the area where the VX was released and get to fresh air. Quickly moving to an area where fresh air is available is highly effective in reducing the possibility of death from exposure to VX vapor. If the VX release was outdoors, move away from the area where the VX was released. Go to the highest ground possible, because VX is heavier than air and will sink to low-lying areas. If the VX release was indoors, get out of the building.

Remove any clothing that has liquid VX on it, and if possible, seal the clothing in a plastic bag. Then seal the first plastic bag in a second plastic bag. Removing and sealing the clothing in this way will protect you and others from any chemicals that might be on your clothes. If helping other people remove their clothing, try to avoid touching any contaminated areas, and remove the clothing as quickly as possible. Rinse the eyes with plain water for 10 to 15 minutes if they are burning or vision is blurred. As quickly as possible, wash any liquid VX from the skin with large amounts of soap and water. Washing with soap and water will protect people from any chemicals on their bodies.

If VX has been ingested (swallowed), do not induce vomiting or give fluids to drink. Seek medical attention right away. Stay calm. Dial 911 and explain what has happened. Wait for emergency personnel to arrive.

VX poisoning is treated with antidotes and supportive medical care. The most important thing is for victims to be rapidly decontaminated and get medical treatment as soon as possible.

People may not know they were exposed to VX because it has no odor. For a list of symptoms, view the following page: VX Exposure Symptoms

Mild or moderately exposed people usually recover completely. Severely exposed people are not likely to survive. Unlike some organophosphate pesticides, nerve agents have not been associated with neurological problems lasting more than 1 to 2 weeks after the exposure.

Recovery from VX exposure is possible with treatment, but the antidotes available must be used quickly to be effective. Therefore, the best thing to do is avoid exposure. Leave the area where the VX was released and get to fresh air. Quickly moving to an area where fresh air is available is highly effective in reducing the possibility of death from exposure to VX vapor. If the VX release was outdoors, move away from the area where the VX was released. Go to the highest ground possible, because VX is heavier than air and will sink to low-lying areas. If the VX release was indoors, get out of the building.

If people think they may have been exposed, they should remove their clothing, rapidly wash their entire body with soap and water, and get medical care as quickly as possible. Quickly take off clothing that has liquid VX on it. Any clothing that has to be pulled over the head should be cut off the body instead of pulled over the head. If possible, seal the clothing in a plastic bag. Then seal the first plastic bag in a second plastic bag. Removing and sealing the clothing in this way will help protect people from any chemicals that might be on their clothes. If clothes were placed in plastic bags, inform either the local or state health department or emergency personnel upon their arrival. Do not handle the plastic bags. If helping other people remove their clothing, try to avoid touching any contaminated areas, and remove the clothing as quickly as possible.

As quickly as possible, wash any liquid VX from the skin with large amounts of soap and water. Washing with soap and water will help protect people from any chemicals on their bodies. Rinse the eyes with plain water for 10 to 15 minutes if they are burning or if vision is blurred. If VX has been ingested (swallowed), do not induce vomiting or give fluids to drink. Seek medical attention right away. Dial 911 and explain what has happened.

A person’s clothing can release VX for about 30 minutes after contact with VX vapor, which can lead to exposure of other people.

Antidotes are available for VX. They are most useful if given as soon as possible after exposure.

Following release of VX into the air, people can be exposed through skin contact, eye contact, or inhalation (breathing in the VX mist). Though VX does not mix with water as easily as other nerve agents do, it could be released into water. Following release of VX into water, people can be exposed by drinking contaminated water or getting contaminated water on their skin. Following contamination of food with VX, people can be exposed by eating the contaminated food.

VX is primarily a liquid exposure hazard, but if it is heated to very high temperatures, it can turn into small amounts of vapor (gas). A person’s clothing can release VX for about 30 minutes after contact with VX vapor, which can lead to exposure of other people.

VX breaks down slowly in the body, meaning that repeated exposures to VX and/or other nerve agents can have a cumulative effect (build up in the body). Because VX vapor is heavier than air, it will sink to low-lying areas and create a greater exposure hazard there.

The extent of poisoning caused by VX depends on the amount of VX to which a person was exposed, how the person was exposed, and the length of time of the exposure. Symptoms will appear within a few seconds after exposure to the vapor form of VX, and within a few minutes to up to 18 hours after exposure to the liquid form.

VX is the most potent of all nerve agents. 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. It is 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 the chemical 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.

VX is the least volatile of the nerve agents, which means that it is the slowest to evaporate from a liquid into a vapor. Therefore, VX is very persistent in the environment. Under average weather conditions, 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.

VX has been used in the past and may also be used again.

VX breaks down slowly in the body, meaning that repeated exposures to VX and/or other nerve agents can have a cumulative effect (build up in the body). Because VX vapor is heavier than air, it will sink to low-lying areas and create a greater exposure hazard there.

It is possible that VX or other nerve agents were used in chemical warfare during the Iran-Iraq War in the 1980s.

People can get more information by contacting the agencies listed on this page: Biological / Chemical Agent Information