What are the pros and cons of liquid nitrogen?

Remember that the air we breathe is 78% nitrogen, so we naturally 'consume' nitrogen every minute. The propellants in an aerosol can however, may contain other ingredients or contaminants that might pose a health risk should you consume them, so I wouldn't advise it. Liquid nitrogen poses a danger due to its extreme cold: it's liquid below −321 °F! That can easily kill the cells in your body! When scuba diving, nitrogen from the high pressure air in your tank will dissolve in your blood and if you ascend too rapidly or after too long breathing the high pressure air, the nitrogen dissolved in your blood can fizz like a warm soft drink when you open the cap, causing bubbles that exert pressure in your joints where the blood vessels are constricted. This causes pain called 'the bends' and requires your repressurization and then gradual decompression in a special device called a decompression tank or room. Nitrogen has no taste or smell so what you might taste was there already or is a contaminant from the airduster you used. By the way, the reason the airduster propellant feels cold is due to the release of pressure on the compressed gas. Why do you think that happens? Here's a hint: it has nothing to do with evaporation.