The chemical structure is R2N−N=O, where R is usually an alkyl group.[2] They feature a nitroso group (NO+) that are "probable human carcinogens",[3] bonded to a deprotonated amine. Most nitrosamines are carcinogenic in animals.[4] A 2006 systematic review supports a "positive association between nitrite and nitrosamine intake and gastric cancer, between meat and processed meat intake and gastric cancer and oesophageal cancer, and between preserved fish, vegetable and smoked food intake and gastric cancer, but is not conclusive".[5]
^California Water Boards, State Water Resources Control Board, "Nitrosamines", 09 December 2024