Tear gas is a general term for chemicals that irritate the skin, lungs, eyes, and throat. There are immediate and potential long-term health effects from exposure.
Tear gas can cause more severe symptoms in people with underlying health conditions.
Most people recover quickly from tear gas effects. However, they should still seek medical advice if they come into contact with these substances.
Image credit: KATHRYN ELSESSER/AFP via Getty Images
Despite the name, tear gas is not a gas. It consists of solid or liquid chemicals, usually within a spray or powder. These substances react with moisture to cause pain and irritation. This is why it mainly affects moist areas of the body, such as the eyes, mouth, throat, and lungs.
Tear gas may consist of many different chemicals. These include:
- chloroacetophenone (CN)
- chlorobenzylidenemalononitrile (CS)
- chloropicrin (PS)
- bromobenzylcyanide (CA)
- dibenzoxazepine (CR)
- combinations of different chemicals
Other names for types of tear gas include mace, pepper spray, capsicum spray, and riot control agents. The strength of tear gas varies. Exposure to a more concentrated version or prolonged exposure can worsen symptoms.
Tear gas was initially developed as a chemical weapon for military use. These chemical weapons are now banned in warfare. However, they are commonly used by police or military personnel to break up crowds, or at protests to stop the movement of people.
There are strict guidelines for tear gas use in public. These include firing tear gas from a distance, only using it outdoors, and using the lowest possible strength chemical mix.
The immediate effects of tear gas on the eyes include:
- watering, burning, and redness of the eyes
- blurred vision
- burning and irritation in the mouth and nose
- difficulty swallowing
- nausea and vomiting
- difficulty breathing
- coughing
- wheezing
- skin irritation
- rashes
A person may also feel a tight sensation in the chest, or feel they are choking.
Tear gas effects should go away in 15–20 minutes.
As well as tear gas exposure on the body, the canisters used to fire these substances can also cause injury. They can be hot and may cause burns. Canister impacts may also result in damage to the face, eyes, or head.
If a person leaves the area where tear gas is present, and their symptoms go away soon afterward, their risk of long-term injury is low. However, scientists still do not know enough about the lingering effects of tear gas on the body.
Exposure to tear gas indoors, or in large amounts, may have serious health effects. These include:
A 2017 study of data collected over 25 years looked at tear gas effects on the body. The chemicals and canisters used to release them have caused severe injuries, permanent disability, and death.
There were two recorded fatalities out of 5,910 people in this study. In the first, the release of tear gas in a person’s home caused death by respiratory failure. The second death involved a tear gas canister impact that caused a fatal head injury.
In this study, 58 people reported a permanent disability after tear gas exposure. These disabilities included:
- respiratory problems
- mental health effects
- blindness
- brain injury
- loss of the use of limbs
- limb amputation
- skin conditions
People with respiratory conditions have a higher risk of serious symptoms after tear gas exposure. These conditions include asthma and chronic obstructive pulmonary disease. There is also a risk that it could cause someone to stop breathing.
The risk of injury from tear gas is greater indoors than outside. Tear gas that becomes trapped inside can increase a person’s exposure to these chemicals.
Firing multiple tear gas canisters can increase the concentration of tear gas in the air. This may cause more severe symptoms.
Firstly, people need to get away from the tear gas. They should leave the building if they are indoors, get fresh air, and try to find higher ground to stay above the chemicals. If there is tear gas outdoors, people should stay inside a building with the windows and doors shut.
They should also cover their mouth and nose with a clean cloth or the inside of a jacket. A dust mask and goggles may offer some protection from tear gas.
A person should remove contaminated clothing as quickly as possible, without pulling it over their head. They can seal these clothes in a plastic bag and arrange for professional disposal.
People should wash their face and body with mild soap and water to remove the chemicals. They can use a lot of water to dilute the tear gas substances quickly. They should also wash glasses or jewelry before they wear them again.
People who experience chemical burns need to seek medical attention. The standard treatment is to rinse all traces of the chemical off the skin, cool with water, and apply a dressing.
If people have burning or watering eyes, they can rinse them for 10–15 minutes with clean water. They should also remove contact lenses. The aim is to remove all traces of chemicals to prevent further eye damage.
A person who has breathing problems after tear gas exposure may need oxygen. Asthma medication can widen the airways and help someone breathe.
No evidence shows that home remedies, such as soaking a cloth in apple cider vinegar or sniffing an onion, are effective.
People should always seek immediate medical attention after tear gas exposure. The effects of these chemicals can be serious. They can call 911 for advice, and a poison control center can provide more information on tear gas.
At low strength, the effects of tear gas should last no longer than 20 minutes. People should get away from the chemicals and wash any traces from their bodies to help limit damage to their health.
Those with respiratory conditions have a higher risk of severe symptoms and long-term health issues following exposure.
The canisters used to fire tear gas can also cause serious injury that may result in disability. People should seek immediate medical attention after contact with tear gas.