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The Continuing ‘Tear Gas’ Debate


The national semantics exercise over “pepper balls” and “tear gas” has continued.

On CBS’ “Face the Nation,” Attorney General William Barr was asked if it was appropriate for the U.S. Park Police “to use smoke bombs, tear gas, pepper balls, projectiles at what appeared to be peaceful protesters” outside the White House on June 1. Barr objected to the description of “pepper spray” as a “chemical irritant,” saying, “It’s not chemical.”

But Barr is contradicted by the Centers for Disease Control and Prevention, as well as the Department of Justice, as Dr. Ranit Mishori, senior medical adviser for Physicians for Human Rights and a Georgetown University professor of family medicine, told us.

“Barr should know better and perhaps brush up on his high school chemistry lessons,” Mishori said. “Pepper spray is a chemical irritant. Period. The CDC classifies it as a chemical irritant, as does his own Department of Justice.”

On its website, the CDC says pepper spray is a “riot control agent,” and such agents “(sometimes referred to as ‘tear gas’) are chemical compounds that temporarily make people unable to function by causing irritation to the eyes, mouth, throat, lungs, and skin.” Mishori referred us to a 2009 DOJ Office of Inspector General report on “less-lethal weapons” that describes pepper spray, and the brand name PepperBall system, as “chemical agents.” (It’s worth noting the report also lists “CS Gas (Tear Gas)” in that category.)

As we’ve written, President Donald Trump objected to media descriptions of the use of “tear gas” to disperse protesters near the White House before the president walked to St. John’s Episcopal Church to pose for photos with a Bible. The U.S. Park Police acting chief said in a statement, “No tear gas was used by USPP officers or other assisting law enforcement partners” that night, but said “smoke canisters and pepper balls” were used. Pepper balls contain a pepper spray-like irritant.

We found some sources — including the Scientific American — consider pepper spray a type of tear gas, while others say both chemicals have the same effect on people.

Mishori, of Physicians for Human Rights, told us in an email: “Tear gas and pepper spray both belong to a class of crowd-control weapons known as chemical irritants.” The chemical makeup is different, but the impact on people is similar. “During a protest, it is impossible to tell what chemical is being used as the clinical manifestations are the same.”

Here’s Physicians for Human Rights’ fact sheet on “chemical irritants.”

Pepper sprays “are mostly derived from capsaicin, the spice compound in chili peppers,” the Scientific American explained in 2018. “There are two compounds in common use in this category: OC gas, a concentrated solution of natural capsaicin, and PAVA, a mix of synthetic capsaicin.” OC is the abbreviation for Oleoresin Capsicum.

After we wrote our story, “The Semantics of ‘Tear Gas’ versus ‘Pepper Spray,’” Sgt. Eduardo Delgado, a U.S. Park Police spokesman, told the press it was a “mistake” or an “incorrect term” to say its officers didn’t use “tear gas” on protesters outside the White House on June 1.

Delgado distinguished pepper spray (or pepper balls) from CS, chlorobenzalmalononitrile, and CN, chloroacetophenone, both typically referred to as “tear gas.” CS and CN activate a certain pain receptor, while pepper sprays, or OC, activate another. Both categories of irritants cause pain and burning to mucous membranes, causing tearing, coughing and other irritations.

Delgado told Vox and Business Insider that USPP should have been more specific in its statement.

“We should have said we did not use CS or CN,” Delgado told Business Insider.

“It was kind of a fault on our part just not saying in the first place ‘we did not use CN or CS, we used smoke and pepper balls,’ and that would’ve made it a moot point,” Delgado told Vox. “Some people claim we purposefully tried to mislead by saying ‘we didn’t use tear gas, we used pepper balls.’ … That was not our intention.”

He further said of pepper balls: “I’m not saying it’s not a tear gas, but I’m just saying we use a pepper ball that shoots a powder.”

USPP Acting Chief Gregory T. Monahan, however, issued another statement on June 5, reiterating that USPP “did not use tear gas.”

Trump has left the false impression that law enforcement didn’t use any chemical agent by saying police “didn’t use tear gas,” without mentioning the pepper balls.

Barr has now drawn a fine distinction on how one might define “pepper spray.” In the June 7 airing of “Face the Nation,” he claimed “there was no tear gas used,” but also that “pepper spray” wasn’t “a chemical irritant.”

Barr, June 7: By the way, there was no tear gas used. The tear gas was used Sunday when they had to clear H Street to allow the fire department to come in to save St. John’s Church. That’s when tear gas was used.

“Face the Nation” host Margaret Brennan: There were chemical irritants the Park Police has said–

Barr: No, they were not chemical irritants. Pepper spray is not a chemical irritant. It’s not chemical.

Brennan: Pepper spray, you’re saying is what was used–

Barr: Pepper balls. Pepper balls.

We don’t know the exact ingredients in USPP’s pepper balls, or the brand. We asked, but Delgado only said the ones USPP uses “contain a powder.” An expert quoted in the Scientific American article, however, said tear “gases” are technically powders that look like a mist in the air.

The PepperBall company says its projectiles contain “the most effective chemical irritant available.” Even if pepper balls contain natural, as opposed to the synthetic, capsaicin, medical sources describe the substance as “chemical.” A 2009 article in the journal U.S. Pharmacist, for example, calls capsaicin, and pepper spray, “a chemical compound.”

“Many pepper sprays use a naturally-produced chemical — made of capsaicin, the same ingredient as in chili peppers –  but it is still a chemical,” Mishori said.