Investigation the relationship between nitrite and nitrate in drinking water and gastric cancer (Systematic review)

Back ground: Gastric cancer is the result of abnormal accumulation of a group of cells, which causes the malignancy in the stomach. It is estimated that gastric cancer is the second most common cancer in the world, and each years about seven thousand people in the world die of this disease. Among risk factors of this disease the diet with high nitrite and nitrate is more important, which these compounds in the stomach are converted to carcinogenic nitrosamines. Therefore the aim of this study is to checking the relationship between nitrate and nitrite of drinking water resources and gastric cancer. Method: This review was performed within articles published at PubMed, Google scholar, Cochrane and SID from 2000 to 2019. The keywords were nitrate, nitrite, water and gastric cancer. By searching this database, 68 articles were found, 45 of them were not related with investigating and 12 of them by reading abstract were removed. Findings: Finally 11articles were included in the study, in one laboratory study that performed on 178 samples of drinking water from a high-risk area of gastric cancer, showed that the nitrate level of drinking water was significantly higher (with an average of 109.6 mg/l). Another study showed that nitrate in gastric cancer groups were significantly higher compared to the control group but there was no relationship between plasma nitrite and gastric cancer, also measuring density of nitrite in the gastric fluid in 69 of patients was showed that nitrite provides the abdominal environment for the formation of carcinogenic nitrosamines. In 3 articles don’t have evidence of the relationship between nitrate and nitrite with gastric cancer, while only 1 article said that nitrate and nitrite of diet and drinking water are beneficial for health. Conclusion: While some articles have stated that nitrite and nitrate can cause gastric cancer but 3 articles suggested that there is no relationship between them so need to be more research done at this topic.

کلیدواژه ها:

Nitrate ، Nitrite ، Drinking water ، astric cancer