As part of​ their training, American soldiers are taught not to be afraid of tear gas (or lachrymatory agent, as it’s formally known). A friend of a friend of mine was stationed in the Middle East with the US Military Police during the first Gulf War in 1990. They would enter a tent wearing gas masks. Two canisters of CS (2-chlorobenzalmalononitrile, the most common type of tear gas) would be opened inside the tent. Their instructions were to remove their masks and leave the tent in an orderly fashion. The drill was a success: the whole thing turned into a game. Two platoons would raid each other, gassing their ‘rivals’ out of their tents. They got so used to CS that some of them sprayed it on their eggs in the morning as a substitute for spice: CS, like pepper spray (itself a tear gas), has much the same active ingredient as chilli peppers. The quartermaster was obliged to shut the whole thing down: the two platoons had blown through the entire battalion’s supply.

For most people who have come into contact with tear gas, the experience bears little resemblance to soldiers’ games; neither are the realities of that experience much registered in the spectacular images of tear-gassed demonstrations across the world. A stimulant in small quantities, when ‘consumed’ in higher doses it causes severe pain and other health problems. Many of these were only poorly understood until the early 2000s, when scientists discovered that tear gases are not merely irritants: they are nerve gases that activate pain-sensing nerves, particularly in the eyes. Sven-Eric Jordt of Duke University, interviewed by Vox in the wake of the police’s tear-gassing of protesters and journalists recently in Ferguson, Missouri, describes the sensation as being ‘like cutting an onion, but about a hundred times more severe’.

I experienced the effects of tear gas myself during demonstrations in Athens in 2011. As soon as a canister explodes in your vicinity, your skin starts burning. It becomes hard to breathe because you’re producing so much mucus, your eyes shut involuntarily and it feels as if your head is about to melt. The canister itself is dangerous. It gets hot as the CS, solid in the unopened canister, is turned into an aerosol; touch it without heavy-duty gloves, and it can burn. Prolonged exposure causes severe respiratory problems and heart attacks; it can cause pregnant women to miscarry and can kill people who suffer from asthma and other bronchial problems. And it is not used responsibly. A hundred or 150 canisters might be used to crack down on a rowdy protest. In Athens, when the occupation of Syntagma Square was evicted in June 2011, three thousand canisters were released in a space no bigger than two football pitches. The ambient temperature was well above 30°C, and the gases lingered in the smog for days. Nearby, in the neighbourhood at the foot of the Acropolis where I lived at the time, I would wake up with red eyes, nostrils burning and a throbbing headache.

Some say the Mayans were the first to use capiscum as a weapon against invading conquistadors in 1605. But there is no explicit reference to the use of any form of tear gas in warfare until the First World War, when poisonous gases were used by both sides. The French used the highly toxic ethyl bromoacetate against German troops; the kaiser’s army escalated the conflict by making intensive use of even more lethal compounds, in particular xylyl bromide. All such weapons were subsequently banned for use in warfare under the Geneva Conventions – but not for use against civilians. In the 1960s, communist countries led a push for a total ban, but many states resisted, arguing that the use of tear gas was necessary and relatively harmless as a riot control measure. When the Chemical Weapons Convention was finally signed in 1993, it included exceptions for domestic use, on which the US among others had insisted.

There are about 15 types of tear gas. CS and CN (chlorophenylethanone) are the most popular, while OC (oleoresin capsicum, or chilli pepper oil) is the basis for pepper spray and Mace, in which it is mixed with CN. Others that have been used in the past include chloropicrin (PS), dibenzoxazepine (CR), bromoacetone, benzyl bromide and bromobenzyl cyanide. Each of these is a highly toxic chemical. While the manufacturers’ publicly available safety data paint a clear picture of the toxicity of the chemicals and the potentially grave harm they can cause, they are less informative about what you should do if you are exposed to them. The general instructions say you should move to find fresh air, which will clear your lungs in a few minutes, and wash your eyes with plenty of water. Both instructions require that you leave the place in which the gas was released.

But people who are being tear-gassed usually have no intention of abandoning their position. Gezi Park, Zuccotti Park, Syntagma Square, Gaza: tear gas is used chiefly by state authorities attempting to evict protesters from public space. Activists go online to discuss countermeasures against tear gas, ranging from elementary safety tips (wear surgical masks at demonstrations) to battle tactics (burn tyres and rubbish bins, since the fire consumes the CS in the air), and use social media to exchange advice about how to deal with its effects. Palestinians and Egyptians tweeted advice to occupiers in the US; Greek activists helped Turkish protesters during the occupation of Gezi Park in Istanbul. The local use of tear gas to deal with threats to state authority has the unanticipated consequence of creating a transnational solidarity among protesters.

The advice doesn’t always translate well between different situations. Veterans in Athens say that lemon juice did the trick against tear gas in the 1990s, but it wouldn’t help with what the police in Greece are using now. An Egyptian tweeted that the protesters in Tahrir Square washed their faces with Coca-Cola, but the common wisdom is that a solution of antacids (like Maalox, used to calm stomach acidity) in plenty of water is the best thing to use. All tear gases are based on complex organic molecules, so milk, yoghurt and oil are probably more effective solvents than the water suggested in the safety instructions. Most of them also have acidic components, so acids like lemon and Coca-Cola won’t neutralise them, while water is a slow fix. But household chemicals don’t always cut it. Reports suggest that in Gezi the Turkish police used different types of gas at the same time. A treatment effective against one compound could exacerbate the effects of another.

‘Non-lethal technologies’ are in demand, and governments are spoilt for choice. If you have been gassed in Egypt, Palestine or America, it was most likely with Combined Systems products made in the US. The Bahrainis use French tear gas. The Greek police is supplied by five different companies from all over the world; the canisters I have seen in use were made by Condor in Brazil. Tear gas is the perfect tool for governments increasingly inclined to look on the public as a potential source of disturbance, rather than the source of their democratic mandate. An independent study earlier this year estimated that the market is currently worth $1.6 billion. It can only grow.

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Vol. 36 No. 20 · 23 October 2014

Yiannis Baboulias’s account of the uses of tear gas misses some of the history (LRB, 11 September). CS, the most commonly used agent, was developed at Porton Down in the 1950s. It was tested on UK servicemen with the inducement of weekend leave. Informed consent wasn’t on the agenda. The irritation that CS causes does, as Baboulias points out, involve nerves, but so does a gnat bite. The term ‘nerve gas’ is reserved for those lethal agents that hit the central nervous system and lead to paralysis and death, such as sarin, a Second World War German invention used by Saddam Hussein against the Kurds in Halabja in 1988, and most recently in Syria.

CS is formally a ‘non-lethal’ agent, and to the chemists who make the stuff, a spray not a gas. It was first used extensively in war by the US forces in Vietnam, who pumped it into the tunnels used by the Viet Cong either to suffocate them or to drive them out to be killed. It was not until the 1990s that CS and related agents were banned by the Chemical Weapons Convention for use in interstate conflicts, though, as Baboulias points out, they are permitted for use against a nation’s own citizens.

The first massive use of CS in the UK was by the Royal Ulster Constabulary in Derry’s Bogside in August 1969. More than a thousand canisters of gas were fired. Knowing something of the effect of chemical weapons in Vietnam, I went immediately to Derry together with Russ Stetler, then Bertrand Russell’s assistant, to investigate its effects on civilians. We surveyed the residents of the block of flats that had been the focal point in the battle, and found that just as Baboulias describes, although CS was an irritant, it had no significant impact on the combatants’ capacity to defend the flats. However, it caused considerable distress, most of all to eyes and breathing among the young, the sick and the elderly, especially where the canisters had been deliberately fired into the flats rather than at the street fighters. We gave our survey results to the Himsworth Inquiry established by the UK government in response to public outrage. The inquiry concluded that although by and large CS did not cause lasting injury, police should instruct their targets to keep their eyes closed when the spray was being fired at them.

Hilary Rose
London WC1

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