Most tear gas canisters expire roughly five years after their manufacture date. But over the last two months, protesters have collected and documented munitions that were manufactured up to 20 years ago.
Portland Police Bureau (PPB) officers have deployed OC gas and CS gas (or tear gas) against protesters since the protests against police brutality and racial injustice began over two months ago. When federal officers from the Department of Homeland Security and US Marshals Service arrived in the city at the beginning of July, they too fired CS gas, as well as HC smoke grenades and a range of other chemical weapons.
The number of weapons used and a lack of transparency from both PPB and federal agencies has made it difficult for protesters to pinpoint exactly who is using which weapons against them. (Portland Police and DHS did not respond to the Mercury's request for comment.) But protesters who have become aware of the use of expired munitions have expressed both outrage and alarm.
Gabriel Trumbly, a paralegal who served for six years in the Oregon Army National Guard and has photographed the protests for his independent media company, has picked up tear gas canisters with manufacture dates from 2006, 2008, and 2009. He has one with a manufacture date of 2000.
“They’re deploying pre-9/11 gas on kids,” he said. “They’re literally using gas made before these kids were born.”
India Wynne, a Marine Corps veteran of two tours in Afghanistan who has attended recent protests with the Wall of Vets, said they have seen expired tear gas canisters used by federal officers “every single night.”
Wynne said they have been experiencing chest tightness and are unable to take deep breaths, and originally thought they had contracted COVID-19. Now, after nearly two months of protesting, they believe the symptoms are a result of tear gas exposure.
“We don’t know what chemicals they’re putting out there on us,” they said. “We don’t know what their potency is now. It is not tested. There is no way to know what the physical effects are.”
There is no definitive link between consistent exposure to tear gas and long-term health effects—but that is largely because, according to Dr. Rob Hendrickson, Medical Director at the Oregon Poison Center, no one is supposed to be consistently exposed to the gas.
“It’s relatively unprecedented to use tear gas nightly for weeks or months on end,” Hendrickson said. “That's not how it was intended. The intent was to use it once to disperse a crowd—not to expose someone daily for several months. So we don’t know.”
Even less is known specifically about repeated exposure to expired tear gas. But Hendrickson said that expired gas can be dangerous for two reasons: first, the combustive mechanism in expired canisters can break down and cause gas to release either too quickly or at too high a concentration. Second, the chemical components of the gas can change past their expiration date.
“We don’t know what the contents of those canisters are anymore,” Hendrickson said. “We know it started off as a particular agent, and the company is guaranteeing that before the expiration date. But we don’t know very much about how those agents break down.”
The fact that munitions have expiration dates at all, Hendrickson said, suggests that “the company can’t guarantee that the product will work or contain what it started out containing.”
High concentrations of tear gas present outsize dangers to protesters as well. The Center for Disease Control states on its website that exposure to large amounts of tear gas, particularly in closed settings, can lead to blindness, respiratory failure, and even death—in addition to the standard skin and eye irritation that the substance is designed to cause.
Juniper Simonis, a quantitative ecologist who runs the firm DAPPER Stats, is part of a group of protesters and scientists trying to identify the types and manufacture dates of munitions used by both local and federal officers. They said that misfiring munitions—canisters that do not fire the way they are supposed to—have been a staple of protests in recent weeks.
“The symptoms of the canisters themselves indicate that they’re expired,” they said. “They get really hot, they spin around ridiculously, and they don’t release the smoke in the way they're supposed to. That is a consequence of the canister being used beyond its shelf life, because the canisters degrade and clog the exit mechanism.”
The heat is particularly worrisome. Exposure to heat can cause certain munitions to deteriorate, and, in the case of at least one smoke grenade found by protesters last week, become a “fragmentation grenade.” The grenade's Proposition 65 warning says that it contains chemicals which have been found to cause cancer and birth defects.
The use of tear gas by federal officers and local and state law enforcement agencies downtown has drawn considerable scrutiny in recent days.
Late last week, US Rep. Earl Blumenauer and state Rep. Karin Power (D-Milwaukie) sent a letter to the US Environmental Protection Agency and the Oregon Department of Environmental Quality asking about the risks that expired tear gas pose to public health and the environment as well as information on how the excessive use of tear gas could impact the city’s water supply.
A day earlier, OPB reported that a number of protesters who have been exposed to tear gas repeatedly over the last two months are dealing with a range of irregularities in their menstrual cycles.
The apparent use of expired munitions against protesters in particular has caught the attention of Sen. Ron Wyden’s office, which is actively collecting documentation of the munitions and has a photograph of one tear gas pin used at a recent protest that was manufactured in 2001.