The Science of Making CS Gas “Safe”

The idea that tear gas is "safe" was produced through violent experimentation on working-class colonial subjects

The following is an excerpt from Anna Feigenbaum’s Tear Gas, the groundbreaking book-length history of the chemical weapon. This excerpt begins with a riot in the Bogside, a poor and historically oppressed Catholic neighborhood of Derry, Northern Ireland, in the summer of 1969. The events follow a year of escalating civil-rights marching and agitation in the city: Particularly fresh was the memory of Samuel Devenney, a middle-aged man beaten to death in his home by riot police despite having nothing to do with protests outside.

The Battle of the Bogside

Shortly after Devenney’s death came the controversial Apprentice Boys march, an annual commemorative march that carried the legacy of British force in Northern Ireland, complete with loyalist songs, “done with the utmost arrogance and bravado to show once again who won the battle many years ago.” The parade’s drum and fife bands celebrate Protestant settlers’ defeat of an Irish- and Scottish-led siege on the walled city in 1689.

In the lead-up to the march, a Derry Citizens’ Defence Association formed and met with senior figures of the Apprentice Boys to request the parade be rerouted. Their request was refused. Fearing the troubles to come, some older and younger residents sought refuge outside the Bogside. Barricades went up and calls went out for able-bodied men to come and defend the community. They wove piles of wood and wire modeled after the 1968 barricades of Paris’s boulevards. Young community leader and local MP Bernadette Devlin became a central strategist of the street, directing how to build and where to fortify structures.

On the day of the march, Derry was on edge. Loyalists rounded the city walls, taunting Bogsiders and throwing pennies as insulting symbols of poverty. The Bogsiders stood firm at their barricades. By afternoon, the taunting on both sides turned to stone throwing. As evening fell, the police pushed through the Rossville Street barricade trailed by loyalists, looking like the vanguard of the Protestant militants. Loyalists smashed up windows of the towering Rossville estate, breaching the borders of Free Derry. The Bogsiders shortly regained momentum and, in crowds of a thousand strong, drove the loyalists back to the edge of the neighborhood.

At 11:45 that night, Rossville Street became the first U.K. site of civilian CS gassing. On advice from the Ministry of Defence, the Royal Ulster Constabulary (RUC) sought out CS supplies. “We originally had the CN variety,” explains RUC Deputy Inspector Shillington, “but we have been advised that CS is the more modern and humane type, which in fact is used by the services.” The RUC quickly telephoned the Minister for Home Affairs. While driving from Belfast the Minister approved the deployment. Supplies of CS were brought in from nearby military storage. According to the RUC, the police responsible for discharging CS in the Bogside had received some, “but not enough,” training. Officers were issued 1.5-inch Very pistols with a 70- to 80-yard range for “defense,” as well as canisters to use when withdrawing. All day August 13, they fired CS intermittently in attempts to disperse the crowds. The gas kept coming until 4:30 in the afternoon on August 14.

Throughout this bombardment, the Bogsiders retaliated with petrol bombs, stones, and, when available, returned CS cartridges. On the second day of fighting, a group of Bogsiders positioned themselves atop the Rossville Flats. “The high flats was wonderful,” a Bogsider recalls. “But they needed ammunition, so you had to climb eight stories with a bin bag full of stones.” With men and boys perched defensively on the rooftop, older residents gathered in their homes below, creating milk-bottle-bomb assembly lines, stuffing rags, sugar, flour, and wicks into bottles. The flat roof and periphery railing of the Rossville Flats provided an ideal tower-top defense in this otherwise sunken territory: From this perch, the elevated city walls that daily marked Bogsiders’ social and economic exclusions were for once on lower ground. But the Bogside’s depressed landscape also meant that the air could stagnate; CS hung in the area for hours. At other times the gas traveled, rolling with even the lightest breeze. It eased up into the broken windows of Bogside flats. Police also tried to launch CS atop the Rossville estate in efforts to quell the milk-bottle aerial attacks, but few, if any, of the cartridges made it up those 10 stories. Instead, they smashed through the windows of residents’ homes.

One of these windows led into the room where a 16-month-old infant, Martin, slept. Hearing his baby cry and cough, Martin’s father ran in. He found the room filled with gas. His son was gasping for breath, tears running down his cheeks. His face had gone pale. Martin’s father felt his child might die without attention.

Derry resident Dr. Raymond McClean found himself baffled by the gas’s effects: “Not only were their eyes inflamed and watery, but many of them weren’t able to breathe to such an extent that several were carried in. I didn’t know what we were dealing with.” People didn’t know how to respond. Were they better off opening windows and doors to clear it out, or should they shut them tighter to prevent another round getting in? As its inventors were well aware, gas causes as much psychological fear as it does physical pain . . .

As the gassing went on, coping tips began to trickle in. A U.S. Army veteran who happened to be in Derry at the time offered advice, typed up in a leaflet that circulated around the Bogside streets. French students in the area are also reported to have taught locals how to flush their eyes out with water and hold vinegar-soaked handkerchiefs to their faces. Devlin recalls, “The whole air was saturated . . . and we’d not a gas mask between us. . . . So we made do with wet blankets, with cotton wool steeped in vinegar, with handkerchiefs soaked in sodium bicarbonate.” One elderly resident stood out on her stoop with a bottle of brown vinegar. As Bogsiders passed by, she poured a drop onto their outstretched handkerchiefs —which in many cases were not handkerchiefs at all but scraps of fabric, and in one boy’s case an old pair of ladies’ underpants.

By the end of the 36 hours of CS gassing, a total of 14 50-gram grenades and 1,091 cartridges containing 12.5 grams of CS had blanketed the Bogside. This brought a flurry of media attention, with stories like baby Martin’s causing moral panic to ripple through the country. Facing a PR disaster, the Home Office had to act quickly, setting up yet another tribunal to look into Northern Ireland’s most recent disturbances and announcing that a full medical investigation would be conducted into the effects of CS gas in the Bogside.

The Chemical Defense Establishment

Sir Harold Himsworth, a physician in London, was appointed to lead the medical investigation. Himsworth, an advocate of fusing the skills of politicians and scientists, had served as secretary to the Medical Research Council and presided over the Section of Experimental Medicine at the Royal Society of Medicine. In 1952 he was knighted into the Order of Bath for his contributions to civil service. A 1958 New Scientist article profiling Himsworth’s accomplishments called him a man of undoubted authority, “receptive, courteous and decisive.”

On September 1, 1969, Himsworth and his team arrived in Belfast. Their first stop was the Ministry of Health, where they were briefed on events in Derry by a group of Belfast doctors and government officials. They headed to the GOC Army headquarters for an “off the record” interview with Sir Ian Freeland, director of operations in Northern Ireland, and a briefing on the situation from a brigade commander. This was followed by another press conference in which Himsworth insisted that “there was nothing sinister in the use of CS gas.” Himsworth was “kindly loaned” the Army’s public-relations officer, and by the end of the evening the team had additionally secured help from Colonel Millman, who “proffered any assistance within his power.”

On day two, Himsworth’s committee ventured into the Bogside. Picking their way over rubble and through the ruins of barricades, they were quickly surrounded by locals anxious to tell their stories. They questioned a girl clutching a teddy bear as her mother explained the persistence of her sore eyes and lips. Derry doctor Donal McDermott related that “scores of people had suffered from vomiting, diarrhea and nausea.” A 55-year-old resident reported that her pet budgie had died in its cage; others shared stories of how children’s suffering appeared more acute than adults’. Confused, scared youngsters often rubbed their eyes, worsening the effects. The committee canvassed the area, examining the Rossville Flats and CS cartridges saved by the Citizens’ Association. Himsworth expressed skepticism over media claims that there had been 60 to 100 cases of gastroenteritis and diarrhea. If this were true, he argued, it should have been officially classified as a major crisis; illness at this scale required government notification. What he didn’t see was that, in the middle of a riot, people’s fears of arrest and the frenzy of the commotion bar many from seeking hospital treatment. Even under normal conditions, people in impoverished areas are reluctant to go to hospitals or doctors for digestive problems, preferring to tough it out or use home remedies, but in a city divided along religious, political, and economic lines, seeking formal medical care was even more contentious. This city of two names was also a city of two hospitals: The nearest was staffed by Unionist doctors, and many Bogside residents avoided it, opting instead to cross the border into Ireland and receive treatment there. . . .

Amid these riotous conditions it is difficult to imagine how standard hospital notification procedures would be carried out. But Himsworth, a man of record, sought statistics. He was after authorized laboratory reports, not regular people’s tales of gassed babies or dead budgies. Throughout his diary of the visit, he records residents’ stories of their experiences and effects with suspicion and occasionally derision. For example, a physician at Altnagelvin Hospital reported the case of chronic asthmatic Charles Coyle, age 50. The committee recorded in their notes that the man:

had been getting steadily worse for some years. His story (typically Irish) was that on the night of 12 August he was on the city wall when CS gas was dropped some two or three hundred yards in front of him—he walked up to it and sniffed it. Feeling ill he went into the O’Range Hall where we stayed for a while. He then came out and got another whiff of the gas but walked half-a-mile home. For four days afterward he stayed at home, but didn’t see a doctor.

While it is unclear whether it was Himsworth, his secretary, or the doctor who found this case to be “typically Irish,” the comment’s documentation in a formal log signifies the disposition of the “independent” British investigation toward the civilians whose health and well-being they were documenting. . . .

Himsworth’s committee traveled directly from Northern Ireland to Porton Down, the MoD’s chemical testing facility. Nestled within 16 acres of countryside, Porton Down was a top-secret station for military research and weapons development, running throughout World War II and the Cold War period, and continues to be so in the present day. An estimated 20,000 military “volunteers” went through the facility, many as subjects in experiments on chemical agents. Told that the military was testing treatments for common colds, volunteers were guaranteed safety and given shillings for participation. As Rob Evans uncovered in researching his book Gassed, “They wanted to get away for any type of break, just anything. . . . But sadly very few actually knew what Porton Down was, or what they were letting themselves in for.”

Some of the chemical agents tested on these young men and women included the nerve agent sarin, different mustard gases, and lachrymators—tear gases—as well as other kinds of chemicals, like smoke bombs and dyes. There were skin tests, oral tests, tests of irritants on the eyes, behavioral tests, and gas-chamber tests, among others. “It was hideous,” according to retired officer Patrick Mercer, “a hutted camp, where it seemed to do nothing but rain. There were a series of bunkers to which you were thrust from time to time to be gassed with CS and to go through ghastly exercises underground wearing a gas mask.” Between 1941 and 1985, approximately 8,850 tear-gas tests, mostly of CN, CS, and CR agents, were conducted on more than 2,800 veterans. The development of CS as a riot-control agent began in the 1950s and increased in the 1960s as unrest in Northern Ireland grew.

. . . In 1969, when Himsworth visited, [this] had yet to be exposed [to the public]; the chemical testing facility was running business as usual, operating on what Grimley Evans describes as “wartime ethics.” In an atmosphere of perceived imminent attack, utility reigns supreme and military secrecy often overrides informed consent. On top of this, Porton Down was run by a mixed civilian and military staff. This created levels of secrecy and security clearance that made it difficult to practice any one protocol. It was hard to determine fault when things went wrong. Such claims to layers of organizational complexity tend to evaporate accountability in what Linsey McGoey has called “strategic ignorances.” The atrocity at Porton Down was not only the procedure but the value system. What—and who—made it an issue of scientific importance to directly apply known poisons to people’s skin, lungs, and eyeballs without consent?

The results of the Porton Down experiments played a key role in the Himsworth Committee’s report. Between October 1969 and March 1971, Sir Himsworth and his team held a series of meetings at Whitehall in which they shared scientific findings, correspondence with medical professionals, and laboratory evidence. Their priorities included finding evidence of CS’s effects on the young, the elderly, and pregnant women, as well as people with previous illness. Himsworth also asked the committee to investigate cases of chemical manufacturers repeatedly exposed to CS and to gather “full details of the Vietnam experience.”

Conspicuously absent from the agenda was any reference to the United States’ widespread use of CS and other tear gases to combat civil protests. Himsworth was silent on the crushed labor strikes, civil-rights struggles, and anti-war protests, and even the helicopters that sprayed CS over thousands on the Berkeley campus just four months before the team’s first meeting, all of which were heavily publicized in the United States and discussed at U.N. meetings on the Geneva Protocol.

Tear Gas as a Drug

Amid increasing counterinsurgency efforts in Northern Ireland and in light of these international debates, in February 1970 British Foreign Secretary Michael Stewart drew on the Himsworth Committee’s interim report to announce a new stance: “CS smoke is considered to be not significantly harmful to man in other than wholly exceptional circumstances; and we regard CS and other such gases accordingly as being outside the scope of the Geneva Protocol.” This announcement led to uproar from members of Parliament, NGOs, anti-war groups, and U.N. delegates.

In June 1970 Sir Alec Douglas-Home took over as Foreign Secretary. While he had reservations over this policy change, the MoD was adamant that CS fell outside the Protocol’s restrictions, which deal with substances that were “significantly harmful or deleterious to man—an argument which it rejected.” In addition, if the government were to deem CS deplorable in war, it would be difficult to justify its domestic use as a means of crowd control. The MoD appealed to the “smoke’s” pacifying powers: “CS has saved innocent lives and gave the police and army a much more humane option than batons, bayonets and bullets or bombs.” This position would soon be validated by the Himsworth Committee, which posited that the effects of CS should be considered “from a standpoint more akin to that from which a drug is regarded than from that from which we regard a weapon.” This framing worked to partition the team’s enquiry from concurrent debates over international law happening in Parliament; it was crucial that the public not be led to translate the ethics of combat to the domestic “troubles” in Northern Ireland. These guidelines, given by the Home Office, delineated a particular relationship between humans and tear gas. It asked the scientists to find a way to calculate safety, to measure it in doses. With drug tests in mind, the Himsworth Committee proceeded to consider CS’s effects with the ultimate aim of authorizing its use.

In the final committee report, the team drew attention to some of the problems arising from their task: What did it in fact mean to consider a weapon as a drug? How could safety be measured medically? Investigating CS as a “druglike” substance required two key considerations. First, they had to determine what distinguished a safe dose from a dangerous dose, and to ask whether the difference was great enough that the drug could be certified as safe. Second, they had to examine the side effects. Were they great enough to outweigh the drug’s benefits? “CS is usually used not in relation to a particular single individual, but in relation to a population,” they noted; during a civil disturbance, it is not only “healthy young adults” who face gassing. CS can affect anyone in the vicinity, including “children, the old, pregnant women and the ill, who are exposed inadvertently.” Determining safety and risk in these circumstances, the committee pointed out, was both medical and political.

Unlike most drugs, CS is not administered in a controlled oral or topical dose. It is no antibiotic tablet or eczema cream. Deployed as a fog or smoke, CS consists of tiny droplets that are absorbed through the skin and inhaled through the lungs. Its effects vary with weather conditions, topology, spatial structures, preexisting medical conditions, and personal tolerance levels. These factors make it difficult to determine the exact level of a “dangerous dose.” But “by Command of her Majesty,” Himsworth and his team accomplished just this.

The Himsworth Report

The committee presented clinical, experimental, and observed evidence, doing their best to bracket off any “element of emotion” from their presentation of findings. Extrapolating from animal experiments, since human experience could not be trusted, the Himsworth Committee listed and refuted side effects, detailed dangerous doses, and offered operational guidance. In the end, CS got its clearance for use during civil disturbances. It was labeled safe for the young and old, as well as pregnant women; some warning was given that it should be used with strict guidance in enclosed locations.

. . . Sterilizing the enquiry process from emotion, politics, and personal experience helped Himsworth construct a tidy report, but the scientific method alone could not be trusted to sift through all the laboratory results. The team needed to make sure the press did not get hold of any unappealing experimental data before the publication of the report. During the committee’s eighth, ninth, and tenth meetings, a number of experiments arose showing more severe effects of CS. With mounting pressure to deliver the final report, the chairman had to decide how to handle these unpublished experiments, which became known as the Porton Papers. The committee agreed that the Porton Papers would not be sent out for publication in scientific journals until three to six months after the report was published, as the papers “could be used by hostile parties to confuse the lay public.”

Ultimately, the Himsworth Report trumpeted experimental results over medical observations and continually downplayed the significance of personal testimony. Personal details on patients were only included when it served to mitigate the ill effects of CS. Likewise, social scientists’ claims that CS effects must be considered in their economic and political context were bracketed at the very outset from debate. Suggestions that the psychological conditions of riot situations could have physiological impacts were brought up in the final report, only to be separated out from the “real effects” of CS. The report treated bodily reactions as side effects, as if they were the result of personal dysfunctions or rare allergies to an everyday product, rather than human bodies responding to poisoned air.

Domestically, the Himsworth Report’s stamp of approval freed Britain to further develop more deadly riot-control agents, counterterrorism technologies, and counterinsurgency tactics—using Northern Ireland as a testing ground. Throughout the 1970s, tensions between the military, police, loyalists, and Irish protesters escalated. CS gas became so commonplace that families lined their front doors with towels to stop it from seeping in. It was frequently fired at close range and into enclosed spaces. On one occasion police fired CS into a bus full of people. Political prisoners were frequently gassed, with rights groups claiming that the stronger lachrymatory agent CR was sprayed during the Long Kesh riots in 1974, causing lesions and permanent scarring. In many ways the birthplace of modern notions of “nonlethal” weapons, Northern Ireland was also home to the first use of rubber-coated metal bullets. The year 1978 brought the use of plastic baton rounds (also called plastic bullets), which were made available to police and soldiers. During the 1981 political prisoners’ hunger strike 29,601 rounds were fired at demonstrators, resulting in 7 deaths. Eight years later the official death toll from this “nonlethal” technology reached 17. Now deployed around the world, different kinds of impact munitions, commonly referred to as rubber bullets, are frequently fired through clouds of tear gas.

The Himsworth Report continues to be used by governments around the world to justify the use of tear gas. In 1989 the U.S. State Department invoked it to defend exporting $6.5 million worth of tear gas guns, grenades, launchers, and launching cartridges to Israel. This tear gas was thrown into Palestinian houses, clinics, schools, hospitals and mosques, often in residential areas, by IDF forces in the Occupied Territories. Human rights groups recorded up to 40 deaths resulting from tear gas, as well as thousands of cases of illness. The State Department, facing criticism, cited the Himsworth finding that “the margin of safety in the use of CS gas is wide” and concluded that suspending tear gas shipments “would be inconsistent with US efforts to encourage the use of restraint by Israel and could work to the disadvantage of the Palestinian population in the Occupied Territories.”

Despite a long trail of reports of CS harms that came throughout the 1980s and into the 1990s, it was Himsworth’s report that remained the technical trump card. Every major inquest or “independent enquiry” conducted in the decades to follow reestablished its prominence through processes of expert testimony and citation. These official inquiries worked to maintain dominant structures of scientific knowledge production, affirming the central authority of military research centers and handpicked, government-approved scientific experts. In this system of scientific capital, researchers are encouraged to exchange stamps of safety for professional prestige. With government safety clearances in place, it was time to roll out tear gas in England.