Nitrate and nitrite exist widely in human environment. White to yellowish granular crystal or powder, tasteless, deliquescent, toxic, slightly soluble in alcohol and ether, and alkaline in aqueous solution. Nitrite is ubiquitous in nature, which means that a person will inevitably come into contact with nitrite in all natural and unnatural environments.
Properties of nitrite
Nitrate is converted into nitrite in living plants, and nitrate reductase is at work. The gradual increase of nitrite content in fried leftovers is due to nitrate reducing bacteria. Most nitrate-reducing bacteria found at present like to live under anaerobic and anoxic conditions. It can also be oxidized when it meets strong oxidants, especially ammonium salts, such as ammonium nitrate and ammonium persulfate, which can interact at room temperature to produce high heat and cause combustible combustion.
Refer to the above content: Baidu Encyclopedia-Nitrite