Nitrates in drinking water and cancers of the colon and rectum: a meta-analysis of epidemiological studies |
| |
| Affiliation: | 1. HCA Florida Brandon Hospital Department of Internal Medicine, 119 Oakfield Drive, Brandon, FL 33511, USA;2. University of Kansas School of Medicine Department of Population Health, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA;3. University of Kansas Cancer Center, 4000 Cambridge Street, Kansas City, KS 66160, USA;1. Memorial Sloan Kettering Cancer Center, Department of Surgery, Urology Service, USA;2. VA New York Harbor Healthcare System, USA;3. New York University, Grossman School of Medicine, Department of Urology, USA;4. University of North Carolina, Department of Urology, Lineberger Comprehensive Cancer Center, USA;5. Department of Implementation Science, Wake Forest School of Medicine, USA;6. New York University, School of Global Public Health, Division of Global Health, USA;1. NHMRC Clinical Trials Centre, Faculty of Medicine and Health, The University of Sydney, Camperdown, Sydney, New South Wales 2050, Australia;2. Centre for Health Research, University of Southern Queensland, Toowoomba, Queensland, Australia;3. Deakin Health Economics, School of Health and Social Development, Deakin University, Geelong, Victoria, Australia;4. Development Studies Discipline, Khulna University, Khulna 9208, Bangladesh;5. School of Social Sciences, Western Sydney University, Penrith Campus, New South Wales, Australia;6. The Australian Centre for Public and Population Health Research, Faculty of Health, University of Technology Sydney, Ultimo, New South Wales 2007, Australia;1. Department of Surgery and Endoscopy, Tenwek Hospital, Bomet, Kenya;2. Department of Surgery, Alpert Medical School of Brown University, Providence, RI, USA;3. Biostatistics Branch, Division of Cancer and Epidemiology, National Cancer Institute, Rockville, MD, USA;4. Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, USA;5. Department of Pathology, University of Nairobi, Nairobi, Kenya;6. Mayo Clinic, Rochester, MN, USA;1. Departamento de Medicina Legal, Etica Medica, Medicina Social e do Trabalho, Instituto Oscar Freire, LIM-40, Faculdade de Medicina da Universidade de Sao Paulo (FMUSP), Av Dr. Arnaldo, 455, Sao Paulo, Brazil;2. Centro de Investigação Translacional em Oncologia, Instituto do Cancer do Estado de Sao Paulo, Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo, Av Dr. Arnaldo, 251, Sao Paulo, Brazil;3. Departamento de Cirurgia de Cabeça e Pescoço e Otorrinolaringologia, Hospital Heliopolis, R Cônego Xavier, 276, Sao Paulo, Brazil;1. Aurora Healthcare US Corp, 8 Electronics Ave., Danvers, MA 01923, USA;2. Department of OBGYN, Tufts Medical Center, 800 Washington St, Boston, MA 02111, USA |
| |
| Abstract: | Backgroundsome recent studies have suggested that the risks of colon and rectal cancer increase with exposure to higher concentrations of nitrates in drinking water. This study is a meta-analysis of relevant studies.Methodsliterature published up to June 2021 was accessed and final results abstracted. Two cohort studies and seven case-control studies were analysed, and one case-control study not used because of limited data. Mixed effects meta-regression analysis was used to assess trends in colon cancer, rectal cancer, and colon cancer considered together, with nitrate concentrations in drinking water.ResultsThe usually accepted exposure upper limit for nitrates is 11.3 mg/l NO3-N. However most studies assess a lower range, with only one study providing data over 8 mg/l. Colorectal cancer risk increased by 2.4% (95% limits 0.4–4.5%) per unit increase in nitrate concentration, over a range from very low values to mid-range values. Extrapolation to higher dosages has insufficient data. The trend for rectal cancer is less than that for colon cancer.ConclusionThe increase in colorectal cancer risk with increasing nitrate concentration is lower than in some recent studies, and applies only over a small range. Extrapolation of these results to higher nitrate levels is not warranted. The studies vary greatly in their design, the nitrate concentrations assessed, and in their results. This association is weak and inconsistent, and may be influenced by bias and confounding factors. Any association of drinking water nitrates with colorectal cancer risk is small, and is uncertain. |
| |
| Keywords: | Colorectal cancer Colon cancer Rectal cancer Drinking water Nitrate Meta-analysis |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
