Møller H, Landt J, Jensen P, Pedersen E, Autrup H, Jensen O M
Danish Cancer Society, Danish Cancer Registry, Institute of Cancer Epidemiology, Copenhagen.
Int J Epidemiol. 1989 Mar;18(1):206-12. doi: 10.1093/ije/18.1.206.
Increasing levels of nitrate (NO3-) in drinking water in Denmark is of concern due to the possibility of an associated increase in long-term exposure to endogeneously formed N-nitroso compounds. Using a duplicate portion technique in combination with a qualitative description of diet and other background variables, the total nitrate intake in a Danish rural population and the contribution of drinking water to the total nitrate exposure is estimated. People drinking nitrate-free water have an intake of 37 mg NO3- per day. At 47 mg NO3- per litre, the exposure is increased to 89 mg, about 60% of which originates from the water. At 84 mg NO3- per litre, the daily exposure is 123 mg, 70% of which originates from the drinking water. These crude comparisons between three groups of people are supplemented with quantitative modelling of nitrate exposure at individual level. Apart from drinking water, consumption of vegetables is a major source of nitrate in this population. Using nitrate in overnight urine samples to quantify exposure is less accurate than the duplicate dietary portion technique and tends, in the present study, to underestimate the contribution of water-derived nitrate to total nitrate intake.
丹麦饮用水中硝酸盐（NO3-）含量不断增加令人担忧，因为长期内源性形成的N-亚硝基化合物暴露量可能随之增加。采用双份膳食技术并结合饮食及其他背景变量的定性描述，估算了丹麦农村人口的总硝酸盐摄入量以及饮用水对总硝酸盐暴露的贡献。饮用无硝酸盐水的人群每天摄入37毫克NO3-。当水中硝酸盐含量为每升47毫克时，暴露量增至89毫克，其中约60%来自水。当水中硝酸盐含量为每升84毫克时，每日暴露量为123毫克，其中70%来自饮用水。这三组人群之间的这些粗略比较通过个体水平的硝酸盐暴露定量模型得到补充。除饮用水外，蔬菜消费是该人群硝酸盐的主要来源。使用夜间尿液样本中的硝酸盐来量化暴露不如双份膳食技术准确，且在本研究中往往低估了水源性硝酸盐对总硝酸盐摄入量的贡献。
