Is It Safe to Ingest Dry Ice?

Close-Up Partial View of Scientist Making Experiment With Dry Ice in Chemical Laboratory

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Dry ice is solid carbon dioxide. At -109.3 degrees Fahrenheit (-78.5 degrees C), it's very, very cold! Dry ice undergoes sublimation, which means the solid form of carbon dioxide turns directly into a gas, without an intermediate liquid phase. Here's whether or not you can touch it and what happens if you do.

Consequences of Touching or Ingesting Dry Ice

You can touch dry ice very briefly without doing any harm. You can't hold it very long, or you'll suffer frostbite.

Touching dry ice is a lot like touching something that is very hot, like a hot plate. If you poke at it, you'll feel the extreme temperature and may experience a little redness, but no permanent damage is done. However, if you hold onto a hot plate or a cold piece of dry ice for more than a second or so, your skin cells will burn/freeze and start to die. Extended contact with dry ice causes frostbite, which can lead to burns and scars. It's okay to pick up a piece of dry ice with your fingernails because the keratin isn't alive and can't be harmed by the temperature. Generally, it's a better idea to wear gloves to pick up and hold dry ice. Metal tongs don't work well because the dry ice vaporizes on contact, causing it to move around in the metal grip.

Swallowing dry ice is much more dangerous than holding it. The dry ice can freeze tissue in your mouth, esophagus, and stomach. However, the most significant risk is from sublimation of dry ice into gaseous carbon dioxide. The extreme build-up of pressure could rupture your stomach, causing permanent injury or possibly death. Dry ice sinks to the bottom of drinks, so it's sometimes seen in special fog effect cocktails. The biggest danger probably is when people try to 'smoke' dry ice, where they put a tiny piece of dry ice in their mouths to blow a puff of smoke. Although professional entertainers and teachers may perform this demonstration, there is a real risk of accidentally swallowing the piece of dry ice.