Most of us are likely to think of a science lab when we hear the term “chemical reaction.” In reality, nature is full of endless chemical reactions occurring all the time. We either just don’t see them, like the ones that take place in our own bodies all day long, or we don’t even think about them. But they’re out there, they’re happening, and some of them are more unpleasant than you might think. 

10. The Chlorine Smell In Pools is Actually a Reaction Between Chlorine and Things Like Pee

Have you ever taken a trip to the public pool and that chlorine smell was just so potent it almost made your eyes water as you approached? It’s like a sting in your nostrils and makes you think they must really take their pool cleanliness seriously if they’re adding so much chlorine to it. We have unfortunate news for you.

Chlorine doesn’t normally have a powerful smell at all. But it is a very reactive chemical and so, when it meets other compounds, it can produce a pungent and even dangerous chemical reaction. That smell from the public pool is one such reaction. 

The pool smell is not from chlorine itself but chloramines. You get chloramines when chlorine mixes with things like sweat, oils, cosmetics, and urine. This is the reason some pools tell you to shower before you swim, to remove many of these compounds from your skin. The urine is another matter. 

Even though it seems like that smell means more chlorine which means a cleaner pool, the opposite is true. When the disinfectant chlorine hits your sweat and pee it breaks down into the smelly chloramines which no longer work to clean a pool. So you may want to rethink a swim if you have a potent pool. 

9. A High School Student Lost Her Fingers to a Chemical Reaction in Art Class

Art class was, for many of us, the most fun class in school. You don’t necessarily need to think super hard and you get to be creative. Hard to go wrong with that. But it’s still possible for things to go very wrong. 

In 2007, an art class took a very wrong turn for a 16-year-old girl who was trying to make a sculpture of her hands. The plan was to put her hands in plaster of Paris to make a mold of the hands and then presumably fill the molds with whatever material she was going to sculpt with. Unfortunately, she misheard the teacher who told her to make a clay mold and then fill it with plaster. She was unaware of the chemical process of how plaster of Paris dries.

Like cement, plaster of Paris creates an exothermic reaction when water is added. The powder starts out as gypsum but then is heated, forcing moisture out. So when water is reintroduced, a reverse reaction occurs.

As the substance dries, the water molecules react with the plaster to create heat. With the girl’s hands fully immersed, the mixture heated to 60 C, or 140 F. By this time the plastic was too dry and too thickly packed for teachers to get her out in time. All she could do was endure the slow, steady burns.

By the time she was freed the damage was too severe and she ended up losing all but two of her fingers. 

8. Adipocere Is The Result of a Chemical Reaction Turning Body Fat Into a Waxy Substance In A Coffin

Have you ever thought about what happens to a corpse once it’s been buried? Most of us know that a body will rot and eventually only a skeleton remains, but the process of rotting is an interesting and off-putting one that has several stages. 

At some point in the process your body will produce a substance called adipocere, otherwise known as grave wax. As long as you have suitable conditions in which a body has moisture but little oxygen, the substance can form. 

When your adipose, or fat tissue, decomposes, it can form this waxy substance thanks to the hydrolysis of triglycerides into glycerin and free fatty acids. This is very similar to how we make soap. It gets the nickname thanks to the fact it will have a waxy texture at first but will crumble over time. That said, it can help preserve a body for years.

7. Pistachios Will Spontaneously Combust In the Right Circumstances

People seem to love pistachios. Americans eat 0.7 pounds of them each per year. That makes for a lot of nuts out there and, all things being equal, that’s potentially dangerous. Pistachios are vulnerable to a chemical reaction that can cause them to spontaneously combust.

Pistachios are one of the most dangerous nuts in the world and they need to be shipped and stored carefully. A room full of pistachios could suffocate you because, even after harvest, they absorb oxygen and give off carbon dioxide. 

Because pistachios have low water and high fat, they can be quite flammable. As the nuts absorb oxygen and give off CO2, they’re breaking fats down into fatty acids and this chemical reaction produces heat. If they get warm enough, the fat in the nuts becomes fuel and they can burst into flames. If you’re transporting millions of nuts together in shipping containers, you may ship a pistachio bomb as a result. 

6. Pit Stains Are Caused By a Reaction To Your Deodorant

The global deodorant market is worth nearly $70 billion so you can safely assume most people don’t want to stink or even look like they might stink with those telltale sweat stains. For most people this isn’t too big of an issue but for some people, especially when they wear white, it can be. Have you ever seen a dreaded yellow pit stain? It’s not a desirable thing for most people. But it’s also not technically caused by your sweat, either.

While it may seem like yellow stains are caused by poor hygiene or excess sweating, that’s not the case. Instead, it’s a chemical reaction caused by the deodorant some people choose to wear. Obviously it doesn’t happen to everyone but the aluminum in your deodorant and antiperspirant can react with proteins in your sweat to produce the yellowing agent that stains clothing. 

If it becomes an issue, using an antiperspirant made without aluminum might do the trick to make the stains go away. 

5. A Chemical Reaction Between Tin Foil and Lasagna Causes “Lasagna Cell”

Lasagna is an immensely popular food and with good reason, it’s delicious. It’s the most-loved pasta dish by Millennials, at least according to one survey. But it hides a secret danger most of us have never heard of. 

Lasagna needs to be stored in a glass or plastic dish or not covered with aluminum foil thanks to a chemical reaction called lasagna cell. In so many words, you risk turning your lasagna into a battery if you don’t.

Lasagna is a prime environment for galvanic corrosion if the dish you’re storing it in is made of metal other than aluminum. Because you have a salty solution working as an electrolyte in the form of the sauce, the lasagna will break down the aluminum in the foil and the molecules of foil act as an anode and will try to bond to the dish, which is now a cathode. 

In as little as a few hours you could notice holes in the foil if you have your lasagna stored in the fridge and tiny blobs of corroded aluminum on the surface of your meal. 

4. The Smell of Pennies Is Actually Your Own Odor After Reacting to Pennies

Have you ever smelled a penny and found the odor unusual or offensive? Before you blame that poor, mostly worthless coin you need to know that it’s not the penny’s fault. Pennies don’t smell, it’s just that they cause us to smell.

If you notice an unpleasant odor on a penny or your hands after handling them, it’s actually the result of a chemical reaction between the copper in the coin and oils in your own skin. The same thing happens when you handle iron or brass. Your body will produce different compounds in reaction to the contact with the metals, some that smell worse than others. 

Not everyone produces the same chemical compounds so what you smell after handling pennies could very well differ from what someone else smells. Regardless of how it manifests, what you think of as a metallic odor is just a misperception and it’s actually body odor. 

3. A Chemical Reaction Causes Beer, Weed, and Skunks to Smell Similar

When beer goes bad, we often call it skunky. This is because skunky beer is an unpleasant situation and if you get one that has gone skunky enough it actually reeks a bit like our smelly little mammal friend. That’s not a coincidence, either. The chemical reaction at play is in the same ballpark as what’s going on in a skunk’s hindquarters.

Beer gets skunky when it’s exposed to light. Light interacts with something called iso-alpha acids, which are released when hops are boiled in the brewing process. You want these normally as they’re part of the bitter flavor in beer. But light destroys them.

When they break down, they bind with other compounds in the beer that have sulfur in them and now we’re in skunk stink territory. The compound is called 3-methyl-2-butene-1-thiol or prenythiol. It’s also in weed and if it’s an especially potent or skunky weed, that’s what causes it.

2. Humans Cause Their Own Indoor Air Pollution

Air pollution has been a cause for concern for years now but usually when we talk about it we mean the air outside. It’s a global sort of concern caused by toxic chemicals being burned and pumped into the atmosphere, right? Well, yes. But that doesn’t mean the air in your house is doing a lot better. Turns out humans are polluting the indoor air, too.

Human skin interacts with chemicals in the air in your own home to produce its own sort of polluting haze. Normally, outdoors, the weather and UV rays take care of a lot of these chemicals but that can’t happen inside. Our bodies create what has been described as an “oxidation field.”

Oil in human skin can react with ozone to produce new compounds. Our bodies produce an oil called squalene. When this meets ozone, which is a compound that exists freely out in the world, it produces a compound that further reacts with ozone to make hydroxyl radicals. These can react to all sorts of things in your house and create toxic compounds.

Out in the wild, hydroxyl radicals are natural and helpful in the air. But in an enclosed space like your house they can be more dangerous. There are potential long-term health effects we can’t know about yet depending on what sort of reactions could occur in any home.

This isn’t a new thing, but it wasn’t until covid and concern over indoor air quality that scientists began inspecting the spaces in which we live and how healthy they are. 

1. Babies Produce a Chemical That Makes Women Aggressive But Does the Opposite to Men

Do you think it’s possible for a smell to change your behavior? The idea that you can use pheromones to do such a thing isn’t new, even though there’s not much evidence to suggest humans work that way. That said, there is some evidence that there are chemicals in body odor which can affect human aggression.

We’re not talking average armpit stink here, rather a chemical produced by babies. Hexadecanal is a compound produced in babies’ heads. Ever seen someone sniff a baby like it was a new car? That’s part of what they’re smelling. Research shows this compound reduces aggression in men but has the opposite effect on women, making them more aggressive. 

It’s believed that a reaction like this is a survival technique. If a baby’s smell makes the mother more aggressive, she may become more protective. Conversely, the father, being less aggressive, is less of a threat as a result. Other mammals have similar reactions to various odors.

The world is full of unnatural things that humans have created for better or worse reasons. We make plastic; we make Pepsi; we make poisons. Some of the unnatural substances we create make the world a better place, like medicines. Others, like your average chemical or nuclear weapon, are devastating. Good or bad, however, there are a number of things that it really seems like humans made on their own which actually do occur in nature without our help at all, even if it’s pretty rare. 

10. The Drug GHB Is Made In Your Brain

GHB, or gamma-hydroxybutyrate, has been a fairly well known party drug for some years now. It produces a sense of euphoria and overall good feelings, at least with careful dosing. It’s also used to treat conditions like narcolepsy and even alcoholism.  That said, one of the biggest dangers with GHB is that it can also cause extreme drowsiness, memory loss, unconsciousness and muscle control problems. For those reasons it has also been nefariously used as a date rape drug. 

Despite all the effects and dangers associated with GHB, it can also be lethal in high enough doses, it’s not just some lab creation from a mad scientist. Your body naturally produces GHB in small amounts. It’s produced in your brain through the synthesis of the neurotransmitter GABA. You can find it in your hypothalamus, thalamus and other portions of the brain where it still works as a depressant, just a natural one. 

9. MSG Occurs Naturally in Many Foods

For many years, no food additive was more maligned than monosodium glutamate. Most frequently associated with Chinese food, there was a long campaign against the flavor enhancers as being a dangerous, processed additive that could cause terrible health problems which included headaches and cancer. 

There’s no actual evidence that MSG causes any significant health issues. A lot of the MSG backlash may have actually been based on little more than racism, especially since there was even something called “Chinese restaurant syndrome” which allegedly gave people issues after eating foods prepared with MSG in Asian restaurants. 

What many people lamenting MSG likely never realized was that, despite the chemical-sounding name, it was still a natural product. MSG is found naturally in many foods ranging from cheese to tomatoes. It was initially derived from seaweed. 

The FDA lists MSG as generally safe to eat and has pointed out that, even with people who label themselves as sensitive to MSG, in clinical testing there are no differences between those who consume MSG and those who have a placebo. 

8. Carbonated Water Occurs In Some Springs

SodaStream hit the market a few years ago, giving people the option to make carbonated drinks right at home with just a bottle of water and whatever flavoring they wanted. They’ve also tried to push the idea that their product is healthy because it can give you plain, calorie-free sparkling water just as easily, no need for sugar or chemical flavorings. 

The average American drinks just under 43 gallons of soda per year, so there’s clearly a love of carbonated beverages out there. And while Coca-Cola and Pepsi are making a killing off of what they sell, carbonated water is by no means a product that was just concocted to make drinks more of a novelty. It happens in nature all on its own.

Carbonated water is what you get when you manage to combine CO2 and water. Out in the wild, when volcanic gasses dissolve naturally in water it creates the same fizz you’d get if you forced those gasses into the water with your SodaStream. The major difference is that, a naturally carbonated spring, would likely be very mineral rich as well. 

7. Nuclear Fission Reactors Can Occur in Nature

Of all the things that man has done in the world, it seems like splitting the atom and creating a fission reactor would have to be one of the most unnatural, and yet here we are. Make no mistake, this is incredibly rare and significantly different from what humans can do with a controlled reaction in a planned out nuclear power plant. That said, when you look at the nuts and bolts of it, a nuclear fission reaction can play out in the wild in a similar way to what happens in a reactor. 

Gabon, Africa is famous for once being home to naturally occurring fission reactors some two billion years ago. There were 17 of them in Gabon and their output was very small compared to a modern reactor, around 100 kilowatts. The conditions that allowed the reaction to occur were incredibly rare and precise and required uranium of the right kind to allow for spontaneous fission, plus precise conditions to hold but not interfere with such a reaction, and a moderator to slow down the neutrons. Despite the odds against all of those conditions being met, Gabon proved to have everything in the right place at the right time. The reactors likely ran for a million years, and the waste material managed to be safely stored in the earth.

6. Asphalt Forms Naturally in Tar Pits

Do you spend a lot of time thinking about paving? The US produces about 350 million metric tons of asphalt every year. Over 94% of America’s 2.6 million miles of road are paved, so there’s lots of need for the stuff. And, as luck would have it, it doesn’t need to be produced in a factory. Asphalt is produced in nature and people have been using it as far back as ancient Mesopotamia and Egypt.

Places like Pitch Lake in Trinidad are natural lakes full of asphalt and tar. Ten million tons of the stuff have been mined from the lake since 1867. The asphalt is used all around the world for paving but mining has greatly decreased. This is due, in part, because asphalt is the most recycled product in America. Nearly 70 million tons of it was reclaimed in 2013 alone and almost all of it was recycled and reused. 

5. Antimatter is Made in Bananas

Few things sound more like science fiction than the concept of antimatter. It’s matter, but somehow the opposite, and if matter and antimatter collide, then both will be destroyed. Yes, the science is a lot more complex, but that’s pretty crazy stuff no matter how you slice it. And even more crazy is that antimatter is being on Earth, right this second, and maybe sometimes you even eat it because it’s made by bananas.

Bananas are known for being a good source of potassium but not all potassium is created equal. Potassium-40, an unstable isotope, degrades slowly over time and part of that degradation involves releasing antimatter in the form of positrons. A single banana will release a positron every 75 minutes, more or less. 

The positrons emitted are likely destroyed almost instantaneously when they hit a random electron, but there’s a chance that means they’re emitting photos as well, so there could be tiny, technically visible antimatter explosions around your banana bowl all the time. The numbers are extremely low, in case you’re worried, and can’t pose a threat. 

4. ElectroMagnetic Fields Occur in Oil Pipelines

We know that the Earth has a magnetic field and so do, you know, magnets. So the idea of a natural magnetic field on its own isn’t unusual or unexpected. That said, a natural electromagnetic field and electrical currents forming in oil pipelines does sound unusual. Despite that, it’s a natural phenomenon and sometimes an unintended consequence of how oil pipelines are made and laid out.

Some companies currently offer solutions to demagnetize pipeline as the problem can make welding nearly impossible. But already produced pipelines also have a problem of becoming magnetized and carrying current thanks to conditions like auroral electrojet in the ionosphere, a current that flows above the North Polar region. There’s an electrojet at the South Pole and around the equator, as well. During periods of moderate electromagnetic activity, a current of 50 amps was measured in the Alaskan pipeline. 

3. Eternal Flames Occur Naturally All Over the World

The concept of a universal flame is actually very common. They exist in countries all over the world, usually built and lit as a tribute or monument to something. In Canada, the Flame of Hope was lit in 1989 by Queen Elizabeth with the intention of burning until diabetes is cured. In 1993, Bill Clinton lit one at the United States Holocaust Museum. Belarus has one that was lit back in 1961.

While many of these flames have actually gone out accidentally or, sometimes, been snuffed out intentionally, they were all designed to keep burning so long as someone pays the gas bill. But nature has its own set of eternal flames all around the world that occur thanks to natural gas deposits. 

Erie County, New York has a famous eternal flame at Eternal Flame Falls. To be fair, the flame does go out sometimes since it’s right under a waterfall and people do need to relight it now and then. It’s also a bit of a mystery how that particular eternal flame even exists as the rock in the area isn’t hot enough to have produced the conditions needed, at least as far as we understand how these things work, which means something else produced the gas deposit somehow. 

2. Mechanical Gears Exist in Insects

A gear seems like a simple and utterly fabricated thing. We can trace gears back to the third century in Europe and even earlier in China and the innovation has allowed for some amazing inventions up to the present day including clocks and mills and far more complicated machines.

As remarkable yet seemingly simple as a gear it, it does seem wholly manufactured. You need to cut pieces to fit together in a way that allows for movement and function. It was surprising to learn that nature has created its own gears, something scientists reported in 2013.

A tiny insect called Issus coleoptratus is just three millimeters long and gets around by hopping about. The mechanism that allows them to jump is not the same as what you’d find in a grasshopper, though. Instead, the rear legs of this remarkable creature have naturally formed mechanical gears that allow the legs to lock and rotate as one, then propel the little creature forward. 

To succeed at jumping, the action needs to be precisely coordinated between both legs. The insect is able to launch both legs within 30 microseconds, or 30 millionths of a second. The bug’s brain is not even advanced enough to do that, so instead its skeleton does it automatically, providing the gears to make it happen as it needs to happen. 

1. Benzos/Valium Occur Naturally in Many Staple Crops

Benzodiazepine, sometimes called benzos, are depressant drugs used as sedatives. They can be used as sleeping pills or sedatives and sometimes they are prescribed for anxiety disorders as well. The drugs were hugely popular and, by 1977, benzodiazepines were the most prescribed drugs in the world. People were using them to treat alcohol withdrawal, as a surgical preparation, and for muscle spasms. 

The drugs were gradually replaced with more modern medications that were considered less harmful, at least at the time. Not that benzos no longer exist, they’re just far less popular. But you can also get a natural hit of the drugs and research indicates mammalian brains contain natural amounts of the drugs. 

Turns out, potatoes and wheat both produce substances that are extremely similar, chemically speaking, to benzos as well as others like diazepam, better known as Valium, and lorazepam, better known as Ativan.