On the crisp morning of January 19 in downtown Portland‘s Lownsdale Square, Dr. Juniper L. Simonis of the Chemical Weapons Research Consortium delivered a press release documenting their research into the usage of poisonous hexachloroethane (HC) smoke grenades by Department of Homeland Security agents during the 2020 protests for racial justice.

Image from the the CWRC website

The press release opened with an acknowledgement of the land by two Native women from the community and recognition of the several Indigenous tribes that inhabited the Willamette River Valley prior to colonization. Their acknowledgement of the land and water highlighted the disastrous environmental effects of the usage of poisonous chemical agents on the local salmon population, a sacred primary food source of the Chinook peoples.

Toxic smoke

HC smoke grenade, from Defense Technology’s website

In July of 2020, CWRC’s community-driven scientific research found that DHS agents unleashed an estimated 26 HC smoke grenades upon protesters, local residents, and local houseless communities alike with blatant disregard to the human and environmental consequences of the hazardous chemicals.

Upon ignition, HC smoke grenades not only release HC (itself listed as a hazardous waste by the EPA), but also gaseous zinc chloride, a potentially lethal gas.

From the report provided by Dr. Simonis: “… Zinc Chloride gas combines the corrosive irritation of bleach vapor with the poisoning capacity of zinc metal fumes, a familiar concern to welders.” Immediate effects of exposure to HC smoke include vomiting, difficulty breathing, and chemical burns; long-term effects of HC poisoning may cause cancer and liver damage.

Many people exposed to HC smoke in Portland reported extended lethargy, loss of hair, and being bed-ridden for several days following the exposure.

HC smoke has long been known by governmental agencies to be hazardous to both human and environmental health. It was originally developed in the early 20th Century to be used in open fields and on water. However, as early as the end of WWII the lethality of HC smoke was well documented, and the military began seeking safer alternatives.

The HC smoke grenades being used by law enforcement today are being produced by Defense Technology, a subsidiary of Safariland, LLC.

Hazard warnings removed

Disturbingly, CWRC’s research found that although material safety data sheets (MSDS) from 1993 and 2004 list four hazardous decomposition products, including zinc chloride, by the time the next MSDS was published in 2011 (following a lawsuit in 2008 in which Defense Technology settled for an undisclosed amount), those four hazardous decomposition products were removed from the list.

Again from Dr. Simonis’ report: “That is, in response to being sued by a federal corrections officer for the impact of HC smoke, rather than re-evaluate if the weapon was ok to continue producing, Defense Technology excerpted all mentions of its most toxic aspects, and kept right on selling them.”

Environmental impact

Image from City of Portland study (link to study below)

As well as the human health hazards of HC smoke, the environmental impacts can not be understated. In a storm drain located close to the focal point of protests in downtown Portland, “environmental toxins have been found at extremely elevated levels (10-fold increases).” The stormwater drainage system flows directly into the Willamette River, a “nesting and rearing habitat for Chinook salmon.” This poisoning of the stormwater drainage system creates a chain reaction of detrimental effects; environmental toxins are bioaccumulated by salmon, which are eaten by both humans and protected sea lions.

In addition to the local fauna, local flora has experienced symptoms of HC poisoning. Massive levels of heavy metals have leached into the topsoil in the immediate vicinity of the focal points of the protests, and trees there have shown signs of unnatural defoliation and are expected to have reduced lifetime growth as a result.

Nationwide problem

DHS is not the only government agency known to be in possession of HC smoke grenades. Records show that the Portland Police Bureau purchased HC smoke grenades in 2018, but it is unclear if they have used them. The Milwaukee Police Department purchased 60 HC smoke grenades in advance of the Democratic National Convention last year, and it’s possible that the Denver Police Department used HC smoke against protesters last summer as well.

Given the tremendous harm and potentially fatal consequences of using HC smoke in crowded urban areas, Dr. Simonis is urging all law enforcement agencies currently in possession of HC smoke grenades to decommission their use immediately before causing any further harm to both humans and the environment.

For more information on the impacts of HC smoke and other chemical munitions, please visit the Chemical Weapons Research Consortium website here.


R. W. Harden is a Portland-based freelance writer and historian with a passion for community-based activism. He focuses on local politics, protests, and the ongoing struggle for abolition of the prison-industrial complex in the PNW.