You’ve probably been warned about the cancer-causing effects of radiation; these are energies with scary-sounding scientific names like gamma rays, alpha particles, and ultraviolet light. Indeed, over time, radiation can take a serious toll on our bodies. But at least it’s something confined to places like Chernobyl, right? Well…

In actuality, tons of everyday objects and places emanate trace levels of radiation. While you won’t exactly keel over the second you touch or consume something on this list, it’s helpful to know what contains the stuff. Thankfully, our bodies can handle quite a bit of it, otherwise, we’d be in serious trouble! Just take a look at these surprisingly radioactive objects…

1. Bananas: Because they carry the isotope potassium-40, bananas emit tiny traces of radiation that even a Geiger counter can pick up. But don’t cut ’em from your diet just yet. You’d have to eat about 500,000 bananas before you started feeling queasy.

2. Airport scanners: In an instant, the controversial tool that TSA agents use to quickly search travelers for contraband exposes you to more radiation than you’d see living within 50 miles of a nuclear power plant for a year.

3. Flying: At about 35,000 feet, a six-hour flight from New York City to Los Angeles exposes travelers to radiation levels equivalent to about 400 trips through those airport security body scanners. Yikes!

4. Coal power plants: Thanks to radioactive substances released through smoke, living within 50 miles of a coal power plant would expose you to far more radiation than if you lived the same distance from a nuclear power plant.

The Sunday Leader

5. Brazil nuts: In Brazil, the roots of trees that produce Brazil nuts extend so far into the ground they actually reach radium-rich soil. The radium—a natural source of radiation—then makes its way into the nuts themselves.

6. Older dinnerware: In the 1960s, it was common for dish and pottery makers to use thorium, potassium-40, or even depleted uranium oxide in coating glazes. Eating acidic foods on these plates could leach some of those elements.

kevinspage / YouTube

7. Exit signs: You know those signs lining every hallway at the office or public place that show you the way out? They stay lit without electricity by utilizing a hydrogen isotope called tritium, a harmful radioactive substance if ingested.

8. Fluorescent lights: The cylindrical bulbs that produce that unsettling light in office buildings and classrooms often contain the radioactive isotope krypton-85. However, the other non-radioactive chemicals utilized in these bulbs are even more dangerous.

Master Sgt. Phil Speck / Kentucky Air National Guard

9. Smoke detectors: To actually detect smoke, some smoke detectors utilize americium-241, a radioactive isotope. Luckily, it’s surrounded by foil and stuff, so as long as you don’t eat the hallway smoke detector between hamburger buns, you should be safe.

Hoppy and Jumpy / YouTube

10. Kitty litter: While it’s great for absorbing your cat’s hard work, the bentonite clay that makes up cat litter contains naturally occurring uranium and thorium. This causes a lot of problems when litter ends up in landfills or in drinking water.

Wikimedia

11. Glossy paper: Paper gets its shine from a white clay called kaolin. And as with kitty litter, it’s that clay that makes this radioactive because it contains traces of uranium and thorium.

12. Living in Denver: Cosmic radiation is a real thing, especially for Colorado folk. The sun emits electromagnetic particles and ultraviolet rays, and the people of Denver—a city situated more than mile above sea level—are exposed to about twice as much radiation as those living at sea level.

CNBC

13. Granite countertops: The very counters that make your kitchen pop have trace amounts of uranium and thorium in them. That uranium decays into a gas called radon, which can do some serious health damage. Luckily, the granite keeps most of it contained!

Granite and Marble Specialties / YouTube

14. Grand Central Station: This railway hub in New York City sits on a granite foundation and boasts granite walls, which, remember, holds radiation. In fact, the station emits more radiation in a year than the legal limits imposed on nuclear power plants would allow.

15. One chest X-ray: While it’s no mystery medical scans and X-rays give off radiation, just how much often flies under the radar. A single chest X-ray, in just one second, emits one-fifth of the radiation a nuclear power plant can legally emit in an entire year.

16. A cranial CT scan: If you thought the chest X-ray was bad, a single blast from a CT scan gives off more radiation about eight times the amount nuclear power plants can legally emit in a whole year.

17. Cigarettes: Tobacco leaves contain traces of polonium-210, an element Russian government authorities allegedly used to assassinate Alexander Litvinenko, a political enemy (left). The element can build up in a smoker’s lungs and organs over time.

18. Cell phones: According to the National Cancer Institute, cell phones emit radio waves that may increase the risk of cancer or alter your brain in other yet-to-be-measured ways. Still, a lot of science argues that phones are perfectly safe.

San Diego Union Tribune

19. Fertilizer: When you sprinkle fertilizer on your lawn, you’re laying down soil that’s rich with potassium, phosphorous, and nitrogen. That phosphorous can contain uranium, which is considered “weakly radioactive.” Still, it could make its way into any food grown in that soil!

20. Your own body: You—yes, you!—are a radioactive being. Bodies contain elements like potassium-40, uranium, thorium, and carbon-14, the decay of which allows scientists to determine the age of skeletons with carbon dating.

University of California, Irvine / Flickr

As with all things in life, moderation is key here. Not one of these surprisingly radioactive things can single-handedly give you radiation sickness, but over time, their effects could add up!

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