# What is the effect on humans of using dry ice and liquid nitrogen as food additives?

I have seen on a TV show that some guy uses dry ice (solid $\ce{CO2}$) to make ice cream and on an another TV show, liquid nitrogen ($\ce{N2}$) is used with tequila. Both are edible.

I know that both gases are inert, but could these gases (perhaps in larger concentrations) be poisonous or create any side-effects in our body? If these gases don't create any side effects, what mechanism(s) does the body use to remove these gases from the body?

• To clarify, the ice cream and tequila are editable. Ingesting dry ice or liquid nitrogen would be life threatening. Recently there was a woman in the news that drank a cocktail with liquid nitrogen in it and literately damaged her esophagus and blew her stomach apart. wgntv.com/2015/09/22/… – MaxW Oct 24 '15 at 22:44

Nitrogen has a boiling point of 77K (-196 °C), CO2 melts at 195K (-78 °C). You don't cool down the ice cream or whatever else you want to eat to those temperatures, that would be very unsafe. Both will evaporate or sublimate quickly when they are in contact with warmer material, so there won't be much left once you eat e.g. the ice cream.

Air is composed of 78% N2 and 0.04% CO2, nitrogen gas can only be dangerous when it replaces all the oxygen in the air. Carbon dioxide is toxic at around 7-10% concentration. Both conditions are not realistically achievable by the methods you describe.

The biggest danger I see would be ingesting a piece of dry ice shortly after it was put in a drink, which would be cold enough to hurt.

• The take-home message is that both liquid nitrogen and dry ice have such high vapour pressures that in any sensible scenario you would not actually ingest any above and beyond what is already present in the atmosphere. Less of a food additive and more of a food process. Similarly, supercritical CO2 or dichloromethane is used to decaffeinate coffee but none is retained by the final product. – Richard Terrett Jul 13 '12 at 13:44

Liquid nitrogen is a dangerous substance to handle without proper knowledge. While food created using it will be perfectly safe (79% of the air you breathe is $N_2$, so no risk there), there are dangerous in the perpetration process.

Someone in Germany lost both their arms while trying to use Liquid Nitrogen to produce food at home when they poured the left-over liquid nitrogen down the sink, causing an explosion which took their arm off. (See Bluementhal Style Chef Blows Off His Hands)

$CO_2$ is produced by your body in respiration and breathed out normally. It is also present in carbonated fizzy drinks and sparking wine. The only risk for dry-ice would be if you ate a lump of it, where you might suffer from the cold if it got stuck in your throat.

• The sillyness of liquid nitrogen as a coolant lies in the fact that it has a low heat of vaporisation. "Chef" use is for show, nothing else, a problem in America predominantly. With respect to that ominous explosion in Germany, do You have some reference (date, names?) – Georg Jul 16 '12 at 14:45

To add to the answer from Nick about the dangers and from Georg about the use of liquid nitrogen for flair, a woman recently had her stomach removed to save her life after she consumed a liquid nitrogen alcoholic beverage. You can read about it at on the Yahoo! News web site.

One must be careful with these things and even dry ice can be dangerous enough to cause burns.