A protest march passed by the building where Waddell was working, and he went to see what was happening. Tear gas drifted into the building, and it was all-consuming.
Twenty-eight years later, law enforcement agencies around the world still deploy tear gas and other chemical irritants to control crowds. In the US, clouds of tear gas billowing from canisters and pepper spray drenching the faces of demonstrators have become some of the defining images of , as protesters gather to call for justice for George Floyd and an end to police brutality against Black people.
Riot-control agents like tear gas and pepper spray are banned from use in warfare under the Chemical Weapons Convention CWC. Yet they may still be used for law enforcement and riot control, explains chemical weapons specialist Marc-Michael Blum, founder of Blum Scientific Services, which focuses on analytical testing and training in the areas of chemical and biological defense.
The CWC and local regulations stipulate that certain chemical agents may only be used for riot control when officers give people adequate warning before releasing the agents and people have a reasonable route to escape any gas.
Neither of those conditions makes sense in a battlefield setting, which is one of the reasons tear gas and pepper spray are banned in warfare, Blum says. He adds that the ban in warfare helps prevent conflation of riot-control agents with more deadly chemical weapons. Without any medical attention, the effects of pepper spray and tear gas tend to wear off within 30 min, Blum says, although pepper spray stimulates lung inflammation that can be dangerous for people with existing breathing problems.
The chemical nature of riot-control agents came into sharp focus in the US in early June after federal forces cleared protesters from the streets and sidewalks north of Lafayette Square, in front of the White House. President Donald J. Trump walked through the area to pose for photos and videos in front of St. Barr claimed that no tear gas was used, referring only to the use of pepper balls.
CS is 2-chlorobenzalmalononitrile, a common type of tear gas, and OC stands for oleoresin capsicum, the active ingredient in pepper spray. CS has mostly replaced an older tear gas chemical, known as CN for chloroacetophenone, because CS is less toxic and more potent. Gerbasi is a priest from a nearby Episcopal parish who was on site at St. Pepper balls are similar to paint balls, except that instead of paint, they contain fine-powdered CS, OC, or other chemical irritants, according to the company PepperBall, which holds a suite of patents on the technology.
Upon impact, pepper balls burst and release their contents in a large dust cloud. Tear gas is a slang term that usually means CS in the law enforcement world but can also include OC and other chemicals. OC is an oily extract from hot pepper plants. Weapons makers emulsify it in water and propylene glycol or dissolve it in organic solvents to make aerosol pepper spray. They may also compound it into a powder. OC extract is mostly composed of capsaicin, the same compound that gives spicy food its hotness.
Sriracha, a popular type of hot sauce, lands between 1, and 2, on the Scoville scale, a measure of spiciness. OC pepper sprays, by contrast, clock in north of 2,, on the same scale.
The sweating is likely thanks to a human pain receptor called TRPV1. When pepper spray is inhaled or absorbed by mucous membranes in areas like the eyes or nose, capsaicin makes its way to nerve cells. TRPV1 is a cation channel on those nerve cells that activates in response to capsaicin and related molecules like allyl isothiocyanate, which gives mustard and wasabi their sting. Activating TRPV1 sets in motion a cascade of events that sends pain signals to the brain.
Thus, the sweating. CS is a synthetic molecule that is solid at room temperature. In addition, CS breaks down into various other compounds at high temperatures. If it cannot be washed, it should be put with the contaminated clothing. Disposing of your clothes: After you have washed yourself, place your clothing inside a plastic bag.
Avoid touching contaminated areas of the clothing. Anything that touches the contaminated clothing should also be placed in the bag.
If you wear contacts, put them in the plastic bag, too. Seal the bag, and then seal that bag inside another plastic bag. Disposing of your clothing in this way will help protect you and other people from any chemicals that might be on your clothes.
When the local or state health department or emergency personnel arrive, tell them what you did with your clothes. The health department or emergency personnel will arrange for further disposal. Do not handle the plastic bags yourself.
Seek medical attention right away. Dial and explain what has happened. How exposure to riot control agents is treated Treatment consists of helping the affected person get more oxygen in his or her blood and of stopping agent-caused chemical burns from getting worse. Medications that are used to treat asthma such as bronchodilators and steroids may also be used to help the person breathe. Eye exposures are treated by rinsing the eyes with water until there is no evidence of riot control agents in the eyes.
They were used to clear protesters from a public park so President Donald Trump could walk from the White House to a nearby church for a photo opportunity.
The active compounds in pepper spray are collectively known as capsaicinoids. The most important chemical in OC is capsaicin. This is derived from chilli peppers in a chemical process that dissolves and concentrates it into a liquid.
Capsaicin is the same compound that makes chillies hot, but in an intense, weaponised form. Not all capsaicinoids are obtained naturally.
One called nonivamide also known as PAVA or pelargonic acid vanillylamide is mostly made by humans. PAVA is an intense irritant used in artificial pepper spray.
Rather, tear gas refers to any weaponised irritant used to immobilise people. You can get our highlights each weekend. Portsmouth Climate Festival — Portsmouth, Portsmouth. Edition: Available editions United Kingdom. Become an author Sign up as a reader Sign in. Janice Chambers , Mississippi State University. What is tear gas?
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