Warnings on E 250 from the Italian Association for Cancer Research (AIRC) : Prolonged dietary intake of large amounts of nitrites is associated with an increased risk of developing stomach cancer and oesophageal cancer. Foods containing potassium nitrite (E249), sodium nitrite (E250) and potassium nitrate (E252), found mainly in tinned meat, sausages and processed meats, should therefore be avoided or greatly reduced. Finally, certain antioxidants such as vitamin C (E300) and its derivatives, such as sodium ascorbate (E301) and potassium ascorbate (E303) inhibit the formation of nitrosamines from nitrates and nitrites and are therefore often used in combination in the food industry (1).

Sodium nitrite, a food colour fixative and preservative for meat and fish, contributes to carcinogenesis. The dangerous effect results from the reaction of nitrites with amines to produce nitrosamines. The protective role of garlic oil against abnormalities in the biochemical parameters of metabolism and the oxidative state induced by sodium nitrite has been studied in laboratory animals. From the results, it can be concluded that the administration of garlic plays an extremely useful role in overcoming the negative effects of chronic ingestion of sodium nitrite, which is probably due to its excellent antioxidant properties and highly nutritional values (2).

With regard to intake, particularly with processed meat, sodium nitrite may be linked to the incidence of colon cancer due to nitrite residues and due to intakes. This is reported in a study on laboratory animals (3).

The incident described in this study is certainly a borderline case, unfortunately, but it warns us of the dangers of foodstuffs that are not subject to legal control and of the misinformation of some small-scale food business operators (4).

References____________________________________

(1) http://www.airc.it/cancro/disinformazione/additivi-conservanti-alimentari/

(2) Hassan HA, El-Agmy SM, Gaur RL, Fernando A, Raj MH, Ouhtit A. In vivo evidence of hepato- and reno-protective effect of garlic oil against sodium nitrite-induced oxidative stress. Int J Biol Sci. 2009;5(3):249-55. doi: 10.7150/ijbs.5.249. 

(3) Zhou L, Zahid M, Anwar MM, Pennington KL, Cohen SM, Wisecarver JL, Shostrom V, Mirvish SS. Suggestive evidence for the induction of colonic aberrant crypts in mice fed sodium nitrite. Nutr Cancer. 2016;68(1):105-12. doi: 10.1080/01635581.2016.1102298.

(4) Cvetković D, Živković V, Lukić V, Nikolić S. Sodium nitrite food poisoning in one family. Forensic Sci Med Pathol. 2019 Mar;15(1):102-105. doi: 10.1007/s12024-018-0036-1.