Nitrates and nitrites in drinking water and stomach cancer risk
| Author(s) | |
|---|---|
Strazdas, Lori A | Fulbright program, New York, USA |
Wright, Richard | University of Louisville, Louisville, USA |
| Date Issued |
|---|
2005-09-13 |
Introduction: Some epidemiological studies have shown an association between nitrate levels in drinking water and mortality from stomach cancer. Aim: The aim of our study was to assess a relationship between stomach cancer and nitrates and nitrites level in drinking water. Methods: A case-control study has been carried out in Lithuania. The study included 77 cases aged 25-85, with newly histologically confirmed diagnosis of stomach cancer, and 181 randomly selected controls that were free from cancer and stomach disease. Cases and controls were matched for gender, age (±5yr) and residence. A questionnaire modelled on the Aichi Cancer Centre questionnaire was used to collect information on possible risk factors for stomach cancer. Nitrate and nitrite levels in samples of drinking water were analysed according to ISO 7890:1998 and LAND 38-2000, respectively. Unconditional logistic regression was used to estimate the risk for stomach cancer. Results: After adjustment for age, gender, parents history of cancer, education, smoking, alcohol use, body mass index, and main food items (butter, pork, beef, chicken, cheese, smoked meat, salted meat, carrot, cabbage, tomato, garlic, onion, paprika, fruits), the subjects drinking water with nitrate concentration >50mg/l had an odds ratio 1.00 (95% CI 0.41-2.48) compared with the subjects that drank water with lower nitrate concentration. For people using drinking water with nitrite levels higher than 0.1 mg/l, the adjusted odds ratio was 3.48 (95% CI 0.99-12.29), compared with the persons drinking water with a lower nitrite concentration. Conclusion: The data obtained indicate that nitrite in drinking water may cause stomach cancer, even though the result is not statistically significant.