CBRN event in United States of America on Wed 21st January 2026

Immigration officers in Minneapolis are now using a weapon that’s unfamiliar to many protesters: grenades that spew a noxious green gas.

On Wednesday, Border Patrol chief Greg Bovino made headlines when he hurled a canister of it at a crowd that had gathered at Mueller Park. “I’m gonna gas. Get back. Gas is coming,” Bovino says in the video, filmed by activist Ben Luhmann. The gas has been used repeatedly by Immigration and Customs Enforcement in the Twin Cities, according to Andrew Fahlstrom, who helps lead Defend the 612, a community group opposed to the federal surge. “People are sharing images of” it, he said. “I don’t know the name, but they say it’s more toxic than regular tear gas.” The gas, according to the Minnesota Star Tribune, appears to be made by the company Defense Technology. I reached out to experts to see what they knew about it and whether it really is more dangerous than other chemical munitions. Sven-Eric Jordt, a professor at the Duke University School of Medicine who studies tear gas and its health effects, had an answer for me.

The Defense Technology website, he said, includes a link for each product that is supposed to go to a “safety data sheet,” which should provide safety information. Unfortunately, Jordt discovered, the links were broken. But he found a working link using Archive.org. The green smoke grenade used in Minneapolis is missing from the archive, but Jordt located another product that appears the same—another smoke pocket grenade—except it uses uncolored smoke. He also found a military-style green smoke grenade “that is equivalent but bigger.” These grenades contain worrisome chemicals. “The potassium perchlorate is a significant toxicant and some of it may expose bystanders, but most of it is likely burned,” he says. “The lead and chromium are highly toxic—listed as reproductive toxicants and carcinogens. Again, the amounts are small, but are of concern.” But compared with the CS tear gas pocket grenade, which deploys the kind of tear gas protesters are likely more familiar with, the green gas grenades have a smaller number of toxic constituents. “If exposures are equal, I would consider the CS tear gas pocket grenade to be more toxic than the smoke pocket grenade,” he said. “The green dyed smoke suggests high toxicity to protesters,” he adds, “but the effect is more psychological.”