For $33, you can buy a Defense Technologies hexachloroethane (HC) smoke canister for crowd control purposes.
This is what the City of Milwaukee paid per unit for 60 “Max Smoke” canisters in preparation for the Democratic National Convention in August 2020. It is what Portland Police bought in 2018, and what Denver Police likely used on Black Lives Matter (BLM) protesters this summer.
However, nowhere in the U.S. experienced more HC smoke during the summer of 2020 than Portland, Oregon, where Homeland Security and Border Patrol forces deployed at least 26 such munitions against BLM protesters in July 2020.
BLM protesters were no strangers to tear gas and smoke — after all, the Portland Police had gassed them many times since the George Floyd protests began in late May. But once the feds arrived, protesters knew almost immediately that something was different. People reported new, strange effects that lasted days or weeks after exposure. “I puked. All night,” Gregory McKelvey, activist and campaign manager for Portland mayoral candidate Sarah Iannarone, tweeted on July 26. “This gas feels different and sneaks up on you.” Other protesters and journalists on the ground reported similar bouts of nausea and vomiting, along with loss of appetite, hair loss and a burning sensation that lasted days after exposure.
Dr. Juniper L. Simonis, a Portland-based ecologist and evolutionary biologist, suspected that a new chemical used by federal agents might explain these troubling ailments. To find out, they collected and tested samples from plants, soil, gas mask filters and protesters’ clothing.
Ultimately, they discovered this chemical, while relatively new to Portland, was not new at all. Nor were its side effects unprecedented. On the contrary, scientists and doctors have known about HC smoke — and its potentially lethal side effects — for nearly a century.
The opportunistic use of smoke or fog in battle to conceal movement and supplies is as ancient as war itself. Chemical smoke, however, originated in World War I, when E.F. Berger developed the precursor to HC canisters for France. The munition, which combined powdered zinc and carbon tetrachloride to generate opaque clouds of molten zinc chloride smoke, was intended to obscure troop movements, not for crowd control.
During the interwar years, scientists stabilized the smoke canister by replacing carbon tetrachloride with hexachloroethane, or HC. The improved smoke device still generated zinc chloride along with smaller quantities of phosgene and carbon monoxide. The munition saw heavy use in World War II as a way to obscure harbors, hide supply routes or signal to other units.
Reports of the lethal danger of HC smoke, especially in enclosed areas, began accumulating almost immediately. In 1943, 70 people exposed to HC munitions smoke developed nausea, vomiting, chest tightness and a cough. Ten victims died in the incident. According to a study published in 1954, an 18-year-old man spent six weeks in the hospital after 10 minutes of HC smoke exposure in an enclosed space. A 1963 report found that a fireman died after exposure to the smoke.
Numerous reports from the 1980s showed the dangers of HC exposure. Two elderly women exposed to zinc chloride for 75 minutes fell violently ill, one of whom eventually died. Two soldiers exposed to the smoke required ventilators after inhalation. A 21-year-old man took two months to recover from HC smoke. A different zinc chloride incident killed two men. Five soldiers experienced severe symptoms after breathing HC smoke. Two of these men developed acute respiratory distress syndrome and died.
Evidence of the often-deadly hazards of HC smoke accumulated within the civilian world as well. In 2017, scientists conducted a survey of academic documentation of HC smoke exposure and found that, of 31 documented cases, eight victims died and three experienced permanent lung injury.
The clear and well-established danger of high concentrations of HC smoke inspired the military to issue strict guidelines around its use in 1983. When deploying HC munitions, military personnel must wear gas masks. They must “restrict HC deployment to areas of the installation as far as practically possible from … populated areas” and “Take special precautions to protect higher risk individuals such as those highly allergic, children and the aged.”
So why are police forces across the U.S. using HC smoke in densely populated urban areas against protesters?
Given the many documented cases of injury and death from HC smoke, the National Fire Protection Association’s (NFPA) health rating for the device comes as a bit of a shock: 0 out of 4, or “minimal hazard.”
This rating is especially surprising given that the NFPA rating for zinc chloride — the chemical generated by the reaction between hexachloroethane and zinc oxide — is 3 of 4: “Serious Hazard.” Phosgene and chlorine gas — both munition byproducts — have an NFPA rating of 4: “Can Be Lethal.”
How can a chemical weapon whose byproducts are so dangerous constitute a minimal hazard? Simonis suspects the answer lies in a 2002 lawsuit against HC smoke manufacturer Defense Technologies by Timothy Gamradt, a rural Minnesota prison guard. During a 1998 training exercise, nine guards (including Gamradt) threw an HC smoke canister up a flight of stairs. The munition bounced back and exploded at their feet, where it fumigated the guards with zinc chloride as the exercise continued. Almost immediately, the guards began to experience the assorted symptoms observed in other zinc chloride victims: nausea, vomiting, breathing troubles and headaches. Garmradt’s court case dragged on until 2008, at which point Defense Technologies settled out of court for an undisclosed sum.
The timing of Gamradt’s settlement may help explain the surprising inconsistencies over time between Defense Technology’s Material Safety Data Sheets (MSDS) for HC smoke. Simonis points out that both the 1993 and 2004 MSDS lists, which came out before the settlement, declare zinc chloride as a hazardous byproduct. After their 2008 settlement date, this information changed. The 2011 MSDS byproduct list does not list zinc chloride at all.
The chemical reagents are the same. Why are the chemical byproducts different?
Simonis, who has over a decade of experience in their field, considers this change well beyond unusual. “I have never seen a Safety Data Sheet that has had chemicals removed over time. [Material Safety Data Sheets] have intentionally become more detailed and harmonized for ease of use and interpretation, so the company removing chemicals is antithetical to the concept of safety,” Simonis said.
According to Simonis’s research, federal agents deployed at least 26 HC smoke munitions in downtown Portland throughout late July. “While the canisters were deployed outside, which certainly prevented many deaths, diffusion was limited by crowds of thousands of people, closed tree canopies, cars and tents,” Simonis said. Little wonder protesters and those who lived in the affected area reported the same list of symptoms HC smoke victims have reported for the last 80 years: nausea, vomiting, appetite loss and respiratory distress. The use of respiratory irritants during the COVID-19 pandemic is especially concerning. According to a statement by the Oregon Health and Science University (OHSU), “Chemical means to control crowds has raised great concern among medical professionals as we simultaneously try to manage a global pandemic.” Respiratory damage not only has the potential to increase infection rates but can also lead to more severe cases when infection occurs.
Even if federal agents never again fill the streets of downtown Portland with clouds of toxic zinc chloride, the consequences of its prolific deployment may haunt the City of Roses for many years to come. HC smoke releases heavy metals along with zinc chloride. These elements bioaccumulate in livers and kidneys, where they increase the chance of cancer. This kind of damage may not be evident for many years, but those who live downtown or protested for Black Lives in the summer of 2020 may be at higher risk for kidney and liver problems down the road.
Simonis is also concerned about the long-term effects of these chemicals on the environment. Their analysis of soil, plants and storm drains reveal a far higher concentration of heavy metals than comparable sites elsewhere in the area. Soil samples from affected areas contain higher than normal amounts of cyanide and chromium. Samples taken in August from storm drains — which lead directly to the Willamette River — contained almost 10 times more toxins than comparable sites. Harmful chemicals such as barium, chromium, copper, lead and zinc all seem posed to contaminate Oregon’s ecosystem. Simonis is especially worried about zinc chloride, which causes bone deformities in young fish and thereby threatens Oregon’s salmon: a staple of both commercial fisheries and protected sea lions.
Dr. Paul Tratnyek, a chemist and professor at OHSU’s School of Public Health, agrees that heavy metals may have a deleterious effect on the Willamette or Columbia Rivers short term, but believes the environmental impact will fade with time. “In the long run, [the contamination is] not really going to be noticeable because all these sediments are going to settle out in the bottom of the Portland Harbor.” Portland Harbor, already contaminated with chemical runoff from other disasters, will not be made significantly worse by heavy metal runoff from chemical munitions.
Tratnyek agrees, however, that HC smoke munitions are highly dangerous when used as crowd control. “I was surprised that it was nearly unrestricted for [police] to use these kinds of munitions on protesters.” Tratnyek says that any good-faith review of the subject must result in restrictions on what sort of chemicals police may use against protesters.
What Can Be Done?
Until dangerous chemical munitions like HC smoke are banned domestically as well as abroad, protesters can mitigate the danger with proper equipment. Simonis recommends covering all skin to avoid absorption of zinc chloride smoke. Eye protection is a must. Respirators are important, but even the best filter cannot block everything. The most important way to protect oneself is to move away from the smoke quickly, find fresh air and breathe deeply to expel the poisonous smoke as quickly as possible.
When HC gas contacts bare skin, the best remedy is water — the more pressure, the better. Simonis recommends a garden hose over a shower. Clothing absorbs the smoke and should be re-soaked, then washed separately from other, non-contaminated clothing.
Protesters often attempt to extinguish munitions with water, but Simonis cautions against this when it comes to HC smoke. Water can react with hexachloroethane and zinc oxide to explode and make a bad situation much worse.
None of these solves the root problem, of course: The United States’s routine use of potentially lethal chemical weapons in urban areas, often during peaceful or nonviolent protests, in ways that affect the entire populace as well as the environment. “I plead with all law enforcement agencies who have HC in their arsenal to decommission it immediately,” Simonis said. “There is no reason for any police agency to possess it.”
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