Tabun

Background

Tabun, sometimes known as "GA," is a man-made chemical warfare agent that is a type of nerve agent. Nerve agents are the most toxic (harmful) and fast acting of the known chemical warfare agents.

Nerve agents are similar to a type of pesticide called organophosphates. They are similar in terms of how they work and the kinds of harmful effects they cause. However, nerve agents are much stronger than organophosphate pesticides.

It can be described as:

• Liquid
• Clear or colorless-to-brown, depending on purity
• Tasteless
• Having a faint fruity smell
• A vapor (gas) if heated

Where it is found

Tabun is not found naturally in the environment.

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

How it works

All the nerve agents cause their toxic effects by preventing enzymes from working. Enzymes act as the body's "off switch" for glands and muscles. Without an "off switch," the glands and muscles are constantly working. They may get tired and no longer be able to keep working on things such as breathing.

Compared with other nerve agents, tabun is more volatile than VX (another nerve agent) but less volatile than sarin. Because of its high volatility, tabun is an immediate health threat.

A higher volatility means it is more likely to:

• Evaporate from a liquid into a gas.
• Spread into the environment.
• Remain on surfaces for a shorter period of time.

People can be exposed to the gas even if they do not come in contact with the liquid form. Because of its high volatility, tabun is an immediate health threat.

Signs and symptoms

The level of tabun poisoning depends on the amount and form (gas or liquid) of tabun a person was exposed to. It also depends on how the person was exposed (e.g., skin contact, breathing in gas, etc.) and for how long.

Symptoms likely will appear within a few seconds after exposure to the gas form of tabun. Symptoms will likely appear and within a few minutes to hours after exposure to the liquid form.

People can be exposed to a low or medium amount of tabun by breathing it in, swallowing it, or skin absorption. Exposure to low to medium amounts may lead to some or all of the following symptoms within seconds to hours:

• Abnormally low or high blood pressure
• Blurred vision
• Chest tightness
• Confusion
• Cough
• Diarrhea
• Drooling and excessive sweating
• Drowsiness
• Eye pain
• Headache
• Increased urination
• Nausea, vomiting, and/or abdominal pain
• Rapid (fast) breathing
• Runny nose
• Slow or fast heart rate
• Small, pinpoint pupils
• Watery eyes
• Weakness

Even a small drop of a nerve agent on the skin can cause sweating and muscle twitching where the agent touched.

Exposure to a large amount of tabun in any way can cause these additional health effects:

• Loss of consciousness
• Convulsions (seizures)
• Paralysis
• Respiratory (breathing) failure possibly leading to death

Showing these signs and symptoms does not necessarily mean that a person has been exposed to tabun.

Exposure

If tabun is in the air, people can be exposed through skin or eye contact or by breathing it in. Because tabun vapor (gas) is heavier than air, it will sink to lower areas and increase chances of exposure there.

Tabun mixes easily with water, so it could be used to poison water. If tabun is in the water, people can be exposed by drinking the water or getting the water on their skin.

If tabun is in food, people can be exposed by eating the food. A person's clothes can also release tabun if it touched tabun gas, which can expose other people.

Tabun has a faint fruity smell. However, the smell may not be noticeable or strong enough to give people enough warning that it is near.

What to do if you are exposed

Recovery from tabun exposure is possible with treatment, but the antidotes (cure) must be used quickly to be effective. Therefore, the best thing to do is avoid exposure.

Leave the area

Get fresh air by leaving the area where the tabun was released. Moving to an area with fresh air is a good way to reduce the chances of death from tabun gas.

If the tabun was released outdoors, move away from the area where the tabun was released. Go to the highest ground possible, because tabun is heavier than air and will sink to lower areas.

If tabun was released indoors, get out of the building.

Take off your clothes

Remove the clothing with tabun on it as quickly as possible. Cut clothes off instead of pulling it over the head. If you are helping others, avoid touching unsafe areas.

Throw your clothes away

Put your clothing inside a plastic bag. Tie the bag, and then put that bag inside another plastic bag. Throwing away your clothes this way helps protect you and others from any chemicals that might be on your clothes.

When the local or state health department or emergency team arrive, tell them what you did with your clothes. Do not handle the plastic bags yourself.

For more information about cleaning your body and throwing away your clothes after a chemical exposure, visit "About Getting Clean."

Wash your body

Wash any liquid tabun from your skin with lots of soap and water. Washing with soap and water will protect you from any chemicals on your body.

If your eyes are burning or your vision is blurred, rinse your eyes with plain water for 10 to 15 minutes.

Treatment

Treatment involves removing tabun from the body as soon as possible and providing supportive medical care in a hospital.

Antidotes (cures) are available for tabun. They are most useful if given as soon as possible after exposure.

Long-term health effects

Mildly exposed people usually recover completely. Severely exposed people are less likely to survive.

More information

You can contact one of the following:

• Regional poison control center: 1-800-222-1222
• Centers for Disease Control and Prevention's Public Response Hotline
  • Phone: 800-CDC-INFO
  • Teletypewriter (TTY): 888-232-6348
  • E-mail inquiries: cdcinfo@cdc.gov