Nitrite, a general term for a class of inorganic compounds. Mainly refers to sodium nitrite, sodium nitrite is white to yellowish powder or granular, slightly salty taste, soluble in water. Nitrates and nitrites are widely present in the human environment and are the most common nitrogenous compounds in nature. Nitrate in the human body under the action of microorganisms can be reduced to nitrite, N-nitroso compounds precursor substances.