Tear gas is banned from war — but police still shoot it at protesters, who cough and bleed as a result. At least one has lost an eye.

• Police have fired tear gas into crowds of people protesting across the US this week, from Washington DC, to California, Minneapolis, and Illinois, as Americans speak out against the death of George Floyd.
• Human rights experts say the use of tear gas on civilians should be a weapon of last resort, not an everyday occurrence.
• Tear gas is especially dangerous for children, people with breathing issues, and the elderly.
• Tear gas canisters can cause permanent injuries. At least one protester had his eye taken out this week.

Police have dispatched tear gas on crowds across the US this week.

On Monday evening, shortly before the president emerged from the White House for a photo op, tear gas was dispersed on peaceful crowds gathering nearby to protest the death of George Floyd, and the systemic issues of police brutality that his death represents.

Tear gas has also been fired at crowds out in California, Minneapolis, and Illinois. Some of the injuries the projectile irritant is causing cannot be repaired with fresh air and cold water.

Balin Brake, a 21-year-old Indiana Tech student, lost his right eye after a tear gas canister hit his face during a protest in Fort Wayne over the weekend.

Experts say that tear gassing should be a weapon of absolute last resort, especially because it is so indiscriminate, affecting everyone in an area where it spreads, including peaceful individuals and even police officers.

"I wouldn't go so far as to say there's absolutely no role for tear gas, especially in violent settings," Dr. Rohini Haar, an emergency physician and crowd-control weapons expert with Physicians for Human Rights, told Insider. "But I would say that the level of widespread use — not just in the US, but abroad — and how frequently it's misused, should give people pause."

In 1993, tear gas was classified as a chemical weapon and in 1997 it was banned from use in international warfare. Yet US police continue to use it, legally, against civilians.

"It's very uncommon that the entire crowd is a group of rioters," Haar said. "It's often like an individual, or a very small group within the larger crowd that can be arrested and detained. That's what police are supposed to do."

Tear 'gas' is actually a powder

Tear gas — aka agent CS (2-Chlorobenzalmalononitrile) — was invented a century ago, and has long been used as a weapon to control crowds during times of civil unrest.

Tear gas is not actually a gas. It's a solid, white powder that can be aerosolized when mixed with a solvent. When it's mixed with water, sweat, and oils in our skin, it dissolves into a painful, acidic liquid. Heat and humidity can make it feel even worse.

"We call it a non-lethal weapon or a less-lethal weapon, and we really consider it a safe thing to use," Haar said, but she argues that's a problematic way to think about it. "It's not a 'safe' weapon. All weapons are weapons, and they're just as safe as how you use them."

Tear gas that gets into the eyes can cause temporary blindness, while exposed skin often gets red and feels like its burning. Dispersing tear gas often leads to widespread panic and disorientation in a crowd as well.

Dr. Dean Winslow, an infectious disease physician at Stanford Health Care who's been exposed to tear gas as part of his military training, told Insider "it definitely is going to make people cough and sneeze," which puts crowds protesting in the midst of the coronavirus pandemic at even greater risk of infection.

"I would certainly discourage law enforcement from using those sorts of riot control techniques," he said.

Harr said that children, elderly people, and others with chronic respiratory conditions can have an especially hard time breathing in tear gas. In addition, many black Americans disproportionately have pre-existing conditions like asthma that could make tear gas lethal.

Tear gas is banned from warfare, but continues to be used by police on civilians in the US

"The United States is quick to criticize other nations for the use of tear gas on their protestors," Lecia Brooks, chief workplace transformation officer for the Southern Poverty Law Center, told Insider. "Yet, we use it quite frequently. It's a dangerous chemical agent, regardless of what some people say that police officers or agencies would tell you —that it's safe."

Images of protestors today washing their eyes with water bottles or being bloodied by misfired canisters hearken back to similar photos taken in the US during the Vietnam war protests in the early 1960s; in 1992, when people protested the police beating of Rodney King; and in 2014, when police launched tear gas into crowds of protesters in Ferguson, Missouri, who were rallying against the police killing of Michael Brown.

Human rights experts say police using tear gas on civilians exerting their constitutional right to peacefully assemble is generally excessive.

"Most of the time, it's really used to suppress protest, and that's really one of the fundamental problems with it," Jamil Dakwar, director of the human rights program with the American Civil Liberties Union told The World in 2019.

Tear gas canisters and grenades can be deadly projectiles

The most dangerous part of tear gas is often the package that it seeps out of.

"Tear gas canisters, in our research, are the ones that cause most of the permanent disabilities," Haar said. "Especially when they hit the head or the neck, the eyes, the delicate bones of the face."

Her case study of kinetic impact projectiles (KIPs), published in the BMJ in 2017, found that KIPS, including tear gas canisters, rubber bullets, and bean bag rounds, "have caused serious injury, disability, and death."

Of the 1,981 people who sustained injuries in the 26 studies used for analysis, Haar and her co-authors found 53 had died from their injuries, 71 sustained severe injuries, and 300 suffered permanent disabilities.

Brooks told Insider that while there may be some officers with proper training in launching tear gas canisters, most don't know how to minimize harm when using them. This means instead of simply releasing tear gas, they turn the canisters into dangerous projectiles.

"It's not a humane way nor the proper way to disperse a crowd." Brooks said.

"I've never really seen tear gas work to deescalate tensions or to make anything better," Haar added.

What to do if you are tear gassed: move away, and rinse off

The most important thing to do if you're exposed to tear gas is to leave the area where it's dispersing, seeking fresh air and high ground quickly.

Because tear gas is actually a powder, it can easily linger on clothes and in hair.

"It can get stuck in the cloth, it can get stuck on your shoes, in your lungs, so it's best to get out of it, and then get cleaned up," Haar said.

Flush your eyes well with cold water, and when you get home, take your clothes off carefully and head straight to the shower. Use cool water to reduce heat and humidity, which can make the burn worse.

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