News from CREAL
The findings of a study published in the International Journal of Cancer and coordinated by researchers at CREAL, an allied ISGlobal centre, suggest an association between the risk of colorectal cancer and the ingestion of nitrate in drinking water. Nitrate is a chemical compound found naturally in the environment. However, nitrate levels in water and cultivated land are increased by the intensive use of nitrogen fertilizers in agriculture. Nitrates are also used as preservatives in processed fish and meat. Consumption of these food products leads to the formation of N-nitroso compounds in the body, and there is evidence from animal studies that these compounds are carcinogenic.
The investigators conducted a case-control study (the controls were healthy people having the same characteristics as the patients with cancer) in Spain and Italy between 2008 and 2013. The study population was interviewed about their residential history, the type of water they had consumed since age 18, and their dietary habits. Long-term waterborne nitrate intake was calculated using data on recorded nitrate levels in drinking water, the participants’ residential histories and their water consumption habits. Dietary nitrate intake was estimated on the basis of food frequency questionnaires and published food composition databases. Data was analysed for 1,869 cases and 3,530 controls. Average nitrate ingestion in water ranged from 3.4 to 19.7 mg/day. The associations were stronger in the male population and in participants reporting high levels of red meat consumption.
Espejo-Herrera N et al. Colorectal cancer risk and nitrate exposure through drinking water and diet. Int J Cancer 2016 (in press)