What exactly is in tear gas? Experts weigh in on its effects and the need for controlled use

In recent weeks police officers across the country have tear-gassed crowds in attempts to disperse anti-government protesters.

Tear gas is a chemical weapon banned in war, but is legal in Kenya for law enforcement purposes.

Experts warn that there should be controlled use of it, raising concerns about the effects the substance could have on young children as well as implications of long-term exposure for the population.

When police officers fired tear gas canisters to disperse Kibera residents during the Azimio la Umoja One Kenya protests last week, a four-month-old baby, Precious Mongina, lost her life after coming into contact with the gas.

A tear gas canister reportedly got into the house where baby Precious lay through a gap in the shanty's iron sheet roof, according to the deceased infant's mother Joyce Kemunto.

"I took a piece of cloth and doused it in water and started wiping my child's face with it. It seemed to ease her pain at the time but she was still crying. In the middle of the night, she however started foaming from her nose. I took her to the hospital but she unfortunately passed away," Kemunto told Citizen TV's Lilian Muli.

Lung experts say children are uniquely vulnerable to physiological effects of chemical agents. A child’s smaller lung size compared to adults magnifies the harm of agents such as teargas.

"You wouldn’t want to use this agent indoors especially on a child. If that child was left there unattended then it’s almost next to impossible for this child not to be exposed to the lethal consequences of these agents," Dr. Andrew Owuor, a respiratory specialist, said.

Tear gas also known as CS gas or chlorobenzylidene malononitrile, is a chemical agent that causes eye, nose and throat irritation and inflammation.

"In medical terms we call it a lacrimator agent. These are agents that will make you teary. They are generally used by security agents to disperse crowds," said Dr. Owuor.

"When the teargas is lobbed and the particles are dispersed in the air, the gas tends to irritate your mucus membranes. So your eyes, nose, throat and the outside of your mouth will be affected and so will your lungs if you inhale the gas significantly. Your skin will also be affected."

Tear gas exposure can have a variety of effects depending on the duration and intensity of the exposure, as well as the individual’s age, health, and underlying medical conditions with children being the most vulnerable.

When tear gas is thrown indoors, the exposure could be potentially lethal.

"Sometimes it may cause thermal burns to your throat. It will irritate your airways and you will feel the chest tightening. You may actually get bronchospasms or in simple terms wheezing where you feel like you can't breathe," said Dr. Owuor

Exposure to teargas can also cause respiratory failure or worsen a pre-existing respiratory condition.

"For adults, especially those with pre-existing conditions like asthma or chronic obstructive pulmonary disease, then this can trigger an asthma exacerbation which can be fatal," said Dr, Owuor.

Medics say chronic exposure to these agents can cause eye problems such as glaucoma and cataracts.

"Use of teargas is supposed to be controlled because we know the consequences of using this in residential areas and police officers are properly trained on how teargas is supposed to be used so it's not allowed for indoor use," George Musamali, a security expert, said.

While the availability of tear gas can mean police avoid having to resort to the use of more harmful weapons, police forces use tear gas in ways that the gas was never intended to be used, often in large quantities against largely peaceful protesters.

"We need accountability; this is not happening. All officers are given firearms, they carry live bullets and tear gas canisters. They are, however, just lobbing tear gas canisters without orders and that is why we have the case of a child who died from tear gas smoke inside a house. Someone should take responsibility for this," said Musamali.

The recent incidents raise questions about lack of regulations of appropriate use at the police force.

"We need to have leadership and command in the police force and my observation of what's been happening in the last few days is that we lack command and that’s why police went to an extreme," said Musamali.

"The use of tear gas is controlled, not every person is allowed to lob tear gas towards a crowd.  A police commander is required to identify particular officers so that he can be able to account for every tear gas canister used when dispersing protesters."

Use of other tactics such as firing a water cannon with semi permanent colored dye into the air to disperse crowds has been found not to endanger lives.

"The purple rain is just water. The purple color is used to identify the people who were in a particular crowd because it’s hard to wash off. The itchiness comes from the effects of the teargas the minute you get water on your body it reacts to the teargas," said Musamali.