Chemical warfare

Chemical warfare is the use of toxic chemicals as weapons to cause illness, injury or death. In recent years, government agencies have become aware of the increased possibility of these agents being used on the battlefield and also by terrorists throughout the world. This has prompted extensive training on dealing with chemical attacks for local emergency response teams and hospitals by national government agencies such as the Centers for Disease Control and Prevention (CDC) and the Office of Homeland Security.

Remember, should a terrorist incident involving chemical weapons occur, it's important to listen to directions from your emergency broadcast radio and/or television station. In addition, it's helpful to learn as much as possible about individual likely agents.

Chemical warfare agents can be dispersed through munitions, airborne release, contamination of food or water supplies, or other methods. Exposure may happen through direct skin or eye contact, inhalation, or eating or drinking contaminated food or water.

Generally, chemical agents occur in liquid form. However, some are volatile and may easily change into a vapor if heated. As a vapor, they may be dispersed into the air. Dispersion times vary with each agent. Chemical agents are also often influenced by weather conditions, such as temperature, wind and humidity. They are typically heavier than air, so they'll sink into low-lying areas.

Chemical warfare agents are usually divided into four main categories:

nerve agents
blister agents
blood agents
choking (pulmonary) agents
From there, each agent is further classified according to its potential effects. Below are the basics about the various chemical warfare agents and some of the specific agents within each category.


Nerve agents
Definition
Nerve agents are manufactured chemicals that pose the biggest threat of all chemical warfare agents because they're the most toxic and rapidly acting. Nerve agents are similar to common pesticides, but can be hundreds of times more toxic. As the name implies, these agents affect the nervous system by overstimulating the nerve pathways. There are four main nerve agents: tabun, sarin, soman and VX.

Exposure
Exposure to nerve agents usually comes from inhalation or direct eye or skin contact. Less commonly, these agents can be mixed with food or water and ingested. Exposed clothing can release the chemicals for about 30 minutes, which may then expose others. Sarin, soman and toban evaporate quickly and don

Symptoms
Symptoms of nerve agent exposure may occur within minutes to several hours of exposure. The severity of symptoms depends on the extent of exposure. Symptoms may include:

pinpoint pupils
eye tearing
nausea and vomiting
shortness of breath
runny nose
increased salivation
diarrhea
abdominal cramping
increased urination
twitching
convulsions
Diagnosis
Diagnosis of nerve agent exposure is based on history of possible exposure and characteristic symptoms. The diagnosis may be confirmed with a blood test to measure red blood cell cholinesterase levels, but this test may not be readily available.

Treatment
If you're exposed to a nerve agent, leave the contaminated area immediately. Get into fresh air if possible. Keep in mind that nerve agents are heavier than air and will sink to low-lying areas, such as ditches and trenches, so move to higher ground if possible. Quickly remove your clothing. Cut off any clothing that would need to be pulled over year head. If possible, seal the contaminated clothing (and contact lenses, if you wear them) in a plastic bag, put the bag in a second plastic bag and seal it. Wash all exposed skin with plenty of soap and water. If your eyes are affected, flush them with water for 10 to 15 minutes. Wash eyeglasses with soap and water. Once you've done these initial steps, seek medical care as soon as possible. Antidotes are available for nerve agents, but early treatment is essential.

Complications
Severe exposure to nerve agents can cause paralysis, unconsciousness or death. Survivors of nerve agent exposure may experience residual central nervous system effects for four to six weeks.

Prevention
You can wear a gas mask and protective clothing to protect yourself from exposure to nerve agents. Make sure your gas mask is fitted individually and you understand how to use the equipment properly.


Blister agents
Definition
Blister agents are manufactured chemicals that cause blisters on the skin or mucous membranes on contact. Blister agents damage the skin, eyes and respiratory tract. These agents also damage DNA, causing cell death. Blister agents include sulfur mustard (mustard gas or another mustard agent) and lewisite.

Exposure
Exposure to blister agents usually comes through inhalation or direct eye or skin contact. Less commonly, these agents can be mixed with food or water and ingested. Exposed clothing can release the chemicals, which may then expose others.

Symptoms
Symptoms of lewisite exposure develop immediately, while symptoms of mustard exposure may be delayed for 12 to 24 hours. The severity of symptoms depends on the extent of exposure. Symptoms may include:

red, painful skin, followed by large blister formation resembling second-degree burns
eye irritation, pain, swelling and tearing
runny nose and sneezing
nosebleed
shortness of breath
cough
abdominal pain
diarrhea
nausea and vomiting
Diagnosis
Diagnosis of blister agent exposure is based on history of possible exposure and characteristic symptoms.

Treatment
If you're exposed to a blister agent, leave the contaminated area immediately. Get into fresh air if possible. Keep in mind that blister agents are heavier than air and will sink to low-lying areas, such as ditches and trenches, so move to higher ground if possible. Quickly remove your clothing. Cut off any clothing that would need to be pulled over year head. If possible, seal the contaminated clothing (and contact lenses, if you wear them) in a plastic bag, put the bag in a second plastic bag and seal it. Wash all exposed skin with plenty of soap and water. If your eyes are affected, flush them with water for 10 to 15 minutes. Wash eyeglasses with soap and water.

Complications
Exposure to blister agents may lead to blindness, chronic respiratory disease, and secondary skin and respiratory infections. The risk for developing lung cancer may also increase. Severe exposure to blister agents can cause shock or death.

Prevention
You can wear a gas mask and protective clothing to protect yourself from exposure to blister agents. Make sure your gas mask is fitted individually and you understand how to use the equipment properly.


Blood agents
Definition
Blood agents include arsine and cyanide gases such as hydrogen cyanide and cyanogen chloride. Arsine damages red blood cells. Cyanide interferes with the ability of cells to metabolize oxygen, causing cell death. Arsine is used in the manufacturing of semiconductors and metals. Cyanide is a natural substance present in some foods and plants. Cyanide agents are easily obtainable because they're used in various manufacturing processes and produced when synthetic materials are burned.

Exposure
Exposure to blood agents usually comes through inhalation or direct eye or skin contact, such as touching contaminated soil. It's also possible to mix cyanide agents with food or water for ingestion. In its gaseous form, cyanide evaporates and disperses quickly in open areas. Exposed clothing can release the chemicals, which may then expose others.

Symptoms
Symptoms of cyanide exposure may develop within minutes of exposure. Symptoms of arsine exposure develop within two to 24 hours. Symptoms may include:

burning sensation in the eyes, nose and throat
nausea and vomiting
headache
rapid breathing
rapid heart rate
dizziness
weakness
seizures
loss of consciousness
respiratory failure
Diagnosis
Diagnosis of blood agent exposure is based on history of possible exposure and characteristic symptoms. Blood tests to identify the chemical involved and the extent of poisoning may be recommended as well.

Treatment
If you're exposed to a blood agent, leave the contaminated area immediately. Get into fresh air if possible. Keep in mind that cyanogen chloride is heavier than air and will sink to low-lying areas, such as ditches and trenches, so move to higher ground when possible. Hydrogen cyanide, however, is lighter than air and will rise instead. Quickly remove your clothing. If possible, to put the clothes in the bag. Cut off any clothing that would need to be pulled over year head. If possible, seal the contaminated clothing (and contact lenses, if you wear them) in a plastic bag using tongs or a similar tool or wearing rubber gloves. Then, put the bag in a second plastic bag and seal it. Wash all exposed skin with plenty of soap and water. If your eyes are affected, flush them with water for 10 to 15 minutes. Wash eyeglasses with soap and water.

Once you've done these initial steps, seek medical care as soon as possible. Antidotes are available for cyanide, but early treatment is essential. There is no antidote for arsine exposure.

Complications
Exposure to arsine may lead to long-term effects such as kidney damage, memory loss and confusion. Exposure to cyanide may lead to heart and brain damage. In some cases, exposure to blood agents may be fatal.

Prevention
You can wear a gas mask and protective clothing to protect yourself from exposure to blood agents. Make sure your gas mask is fitted individually and you understand how to use the equipment properly.


Choking (pulmonary) agents
Definition
Choking agents cause fluid to build up in the lungs, producing an effect similar to drowning. Choking agents include phosgene and chlorine. Large amounts of both chemicals are manufactured for industrial purposes.

Exposure
Exposure to choking agents occurs through inhalation. Once inhaled, the agents affect the respiratory tract very quickly. Exposed clothing can release the chemicals, which may then expose others. It may also be possible to ingest choking agents through contaminated food or water.

Symptoms
Choking agents quickly irritate the eyes and throat. Within two to three hours, more serious symptoms may include:

coughing or choking
chest tightness
wheezing
difficulty breathing
Diagnosis
Diagnosis of choking agent exposure is based on history of possible exposure and characteristic symptoms.

Treatment
If you're exposed to a choking agent, leave the area immediately. Get into fresh air if possible. Choking agents are heavier than air and will sink to low-lying areas, such as ditches and trenches. Quickly remove your clothing. If possible, to put the clothes in the bag. Cut off any clothing that would need to be pulled over year head. If possible, seal the contaminated clothing (and contact lenses, if you wear them) in a plastic bag, put the bag in a second plastic bag and seal it. Wash all exposed skin with plenty of soap and water. If your eyes are affected, flush them with water for 10 to 15 minutes. Wash eyeglasses with soap and water.

Complications
Exposure to choking agents may lead to pulmonary edema (swelling of the lungs). In some cases, exposure may be fatal.

Prevention
Choking agents quickly disperse and will not remain in one area for any length of time. You can wear a gas mask and protective clothing to protect yourself from exposure to choking agents, however. Make sure your gas mask is fitted individually and you understand how to use the equipment properly.


Evacuation
If you're near an area where a chemical agent has been released, you may be told to evacuate. Emergency officials will notify the public by television or radio. Listen carefully and respond quickly to the instructions. You may be told to go to an emergency shelter, followed by directions to the shelter. Emergency shelters often have any supplies you may need. Emergency officials will tell you if you need to bring supplies. Remember to bring your medications with you. Children in school may be sheltered at school. Don't attempt to get to your children in this case.
Planning ahead for emergencies can save lives. If you can't drive or don't have a car, make arrangements in advance for a ride to a shelter. Establish a "family contact" who all family members can call if you're separated. In some cases, remember that out-of-state contacts may be easier to reach by phone than local contacts.

Sheltering in place
You may be advised to "shelter in place," which means staying inside your home or a building to avoid exposure to a chemical agent. Taking shelter inside a car is a last resort because it may not provide enough protection from chemicals.

It's a good idea to prepare your home in advance in the event of a chemical emergency. Designate a room in the house as a shelter room, and keep the following supplies in that room:

battery-operated radio, flashlight and clock
extra batteries
first-aid kit
duct tape
towels and plastic sheeting
scissors
fire extinguisher
blanket or sleeping bag for each family member
bottled water (3 gallons per person)
working telephone
foods that store well and don't require cooking (such as peanut butter, crackers, cereal, granola bars and canned foods)
manual can opener
mess kit or disposable plates and utensils
matches in a waterproof container
basic personal hygiene supplies
plastic garbage bags and ties (for personal sanitation needs)
toilet paper
baby supplies, as needed (such as diapers, formula and bottles)
pet food, as needed
It's important to act quickly and follow all instructions given by emergency officials. Generally, you'll be advised to:

get inside your home immediately
shut and lock all door and windows
turn off the air conditioner, heater and fans
close the fireplace damper
go to a shelter room and shut the door
tape plastic over the windows in the shelter room
place tape over vents, electrical outlets and any other openings
turn on the radio
use the phone only for serious emergencies
Listen to the radio for instructions on when it's safe to leave the shelter and for any additional information or instructions.