(Almost) Everything You Need to Know About Tear Gas

Londoners undergo a gas exercise for civilians, using tear gas, in 1941.
Londoners undergo a gas exercise for civilians, using tear gas, in 1941.
Keystone/Getty Images

Protests against racism and police brutality, triggered by tragic killing of George Floyd at the hands of a Minneapolis police officer, have emerged in every major American city and in countries around the world. In many places, the protestors have been met with heavy resistance from police wielding tear gas—a chemical weapon that dates back to the early 20th century.

What is tear gas?

Tear gas isn’t one specific chemical and, despite the name, it’s usually not even a gas. There are a few different compounds that are used as “lachrymatory agents.” Most of them are solids at room temperature, and get mixed with liquid or gas dispersal agents for use.

Where did tear gas come from?

Tear gases are something that militaries have been messing around with since World War I. Both France and Germany developed and deployed lachrymatory irritants in battle, but there was evidently a bit of a learning curve. According to the U.S. Army’s Combat Studies Institute, the Germans fired some 3000 tear gas shells during one day of fighting in 1914, but the British troops on the receiving end “suffered no ill effects and never suspected they were under chemical attack.”

Shortly thereafter, the Germans had gotten a better handle on things and were using tear-inducing gases to great effect. In 1916, they fired 2000 shells into a French trench system and 2400 French soldiers—blinded, coughing, and crying—quickly found themselves surrounded by German troops in protective goggles.

CS gas would come a few decades later. Its active component, 2-chlorobenzylidene malononitrile, was synthesized by American chemists Ben Corson and Roger Stoughton in 1928 (the CS stands for Corson and Stoughton). Tear gas using it was developed and tested during the 1950s and '60s.

What does tear gas do?

Tear gases irritate the mucous membranes of the eyes, nose, mouth, and lungs, and cause tearing, coughing, burning, and stinging sensations; chest tightness, and difficulty breathing. At higher concentrations, exposure can cause stomach irritation leading to vomiting and diarrhea.

According to German toxicologist Uwe Heinrich, dispersing the gas at a concentration of 1 mg per cubic meter will cause symptoms of irritation. From there, things go sour pretty quickly. A concentration of 10 mg per cubic meter can force trained soldiers to retreat from an area. Ten to 20 mg/m3 or higher can cause serious injury or, depending on the victim and conditions of exposure, death. In one incident reported in a Swiss medical journal, an otherwise healthy adult man was exposed to a tear gas grenade containing just one gram of CS while inside a building. He quickly developed toxic pulmonary edema, a condition where excess fluid collects in the air sacs of the lungs and causes difficulty breathing, and recovered only after weeks of medical treatment.

Shouldn’t tear gas be illegal?

It is, kind of. Tear gases were used in warfare throughout most of the 20th century until 1993, when the Chemical Weapons Convention banned the production, stockpiling, and use of chemical weapons in battle. The international treaty doesn’t apply to nations’ domestic law enforcement, though, so police officers in the United States are free to spray it at civilians, typically as a means of crowd dispersal.

How do you treat tear gas exposure?

If you’re outside, the best antidote to any breathing problems is fresh, untainted air, and time. For high-dose exposure or exposure in enclosed spaces, bottled oxygen or certain asthma medications may be administered to ease difficulty breathing. Any exposed skin should be washed with soap and water and eyes should be flushed with sterile water or saline solution. Some protestors use a solution of baking soda and water on the theory that the basic sodium bicarbonate can weaken the molecules in tear gas and counteract its effects. Others have used milk or milk of magnesia to fight the burning sensation in pepper spray; experts caution that these fluids aren't sterile and could cause infection.

This story has been updated for 2020.

Turn Your LEGO Bricks Into a Drone With the Flybrix Drone Kit

Flyxbrix/FatBrain
Flyxbrix/FatBrain

Now more than ever, it’s important to have a good hobby. Of course, a lot of people—maybe even you—have been obsessed with learning TikTok dances and baking sourdough bread for the last few months, but those hobbies can wear out their welcome pretty fast. So if you or someone you love is looking for something that’s a little more intellectually stimulating, you need to check out the Flybrix LEGO drone kit from Fat Brain Toys.

What is a Flybrix LEGO Drone Kit?

The Flybrix drone kit lets you build your own drones out of LEGO bricks and fly them around your house using your smartphone as a remote control (via Bluetooth). The kit itself comes with absolutely everything you need to start flying almost immediately, including a bag of 56-plus LEGO bricks, a LEGO figure pilot, eight quick-connect motors, eight propellers, a propeller wrench, a pre-programmed Flybrix flight board PCB, a USB data cord, a LiPo battery, and a USB LiPo battery charger. All you’ll have to do is download the Flybrix Configuration Software, the Bluetooth Flight Control App, and access online instructions and tutorials.

Experiment with your own designs.

The Flybrix LEGO drone kit is specifically designed to promote exploration and experimentation. All the components are tough and can totally withstand a few crash landings, so you can build and rebuild your own drones until you come up with the perfect design. Then you can do it all again. Try different motor arrangements, add your own LEGO bricks, experiment with different shapes—this kit is a wannabe engineer’s dream.

For the more advanced STEM learners out there, Flybrix lets you experiment with coding and block-based coding. It uses an arduino-based hackable circuit board, and the Flybrix app has advanced features that let you try your hand at software design.

Who is the Flybrix LEGO Drone Kit for?

Flybrix is a really fun way to introduce a number of core STEM concepts, which makes it ideal for kids—and technically, that’s who it was designed for. But because engineering and coding can get a little complicated, the recommended age for independent experimentation is 13 and up. However, kids younger than 13 can certainly work on Flybrix drones with the help of their parents. In fact, it actually makes a fantastic family hobby.

Ready to start building your own LEGO drones? Click here to order your Flybrix kit today for $198.

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The Reason Some People Never Return Shopping Carts, According to Science

Abandoned shopping carts could be a sign of social dysfunction.
Abandoned shopping carts could be a sign of social dysfunction.
adisa/iStock via Getty Images

On the spectrum of aberrant behavior, leaving a shopping cart in the middle of a parking space doesn’t quite rise to the level of homicide. But poor cart etiquette is nonetheless a breakdown of the social fabric, one in which some consumers express little regard for others by failing to return a cart to its proper place. Why does this happen?

In a piece for Scientific American, Krystal D’Costa examined some plausible reasons why shoppers avoid the cart receptacle. It might be too far from where they parked, they might have a child that makes returning it difficult, the weather might be bad, or they might have physical limitations that make returning it challenging. Alternately, they may simply believe it’s the job of the supermarket or store employee to fetch their used cart.

According to D’Costa, cart returners might be motivated by social pressure—they fear a disapproving glance from others—or precedent. If no other carts have been tossed aside, they don’t want to be first.

People who are goal-driven aren’t necessarily concerned with such factors. Their desire to get home, remain with their child, or stay dry overrides societal guidelines.

Ignoring those norms if a person feels they’re not alone in doing so was examined in a study [PDF] published in the journal Science in 2008. In the experiment, researchers observed two alleys where bicycles were parked. Both alleys had signs posted prohibiting graffiti. Despite the sign, one of them had markings on the surfaces. Researchers then stuck a flyer to the bicycle handles to see how riders would react. In the alley with graffiti, 69 percent threw it aside or stuck it on another bicycle. In the alley with no graffiti, only 33 percent of the subjects littered. The lesson? People might be more likely to abandon social order if the environment surrounding them is already exhibiting signs of neglect.

In another experiment, researchers performed the flyer trial with a parking lot that had carts organized and carts scattered around at separate times. When carts were everywhere, 58 percent of people left the flyers on the ground compared to 30 percent when the carts were cared for.

Social examples are clearly influential. The more people return carts, the more likely others will do the same. There will, of course, be outliers. Some readers wrote to D’Costa following her first piece to state that they didn’t return carts in order to keep store workers busy and gainfully employed, ignoring the fact that the primary function of those staff members is to get the carts from the receptacle and back to the store. It’s also rarely their primary job.

Until returning carts becomes universally-accepted behavior, random carts will remain a fixture of parking lots. And ALDI will continue charging a quarter deposit to grab one.  

[h/t Scientific American]