近年来在研究环境与消化道癌症病因上,愈来愈重视强致癌物质亚硝胺及其前体硝酸盐和亚硝酸盐对人体健康的影响。故各种食品中亚硝胺的前体物硝酸盐便成为全世界所关注的一个重要问题。目前,美、联邦德国、法和捷克等国已经制定了限制蔬菜、罐头、肉制品、奶制品中硝酸盐含量的法律。在联邦德国、荷兰和比利时等国。蔬菜进入商店要带注有硝酸盐准确含量的说明书。人体摄取的硝酸盐81.5%来自蔬采,因此,硝酸盐的食量是评价蔬菜质量的关键。部份蔬菜及瓜类作物中,硝酸盐(以无机N含量表示,毫克/公斤)的最低和最高含量列表如下西瓜10-130 茄子2-60 南瓜70-300 In recent years in the study of the cause of the environment and gastrointestinal cancer, more and more emphasis on strong carcinogen nitrosamines and their precursors nitrite and nitrite on human health. Therefore, a variety of food nitrosamines nitrate precursor has become an important issue of concern around the world. At present, the United States, the Federal Republic of Germany, France and the Czech Republic and other countries have put in place restrictions on the content of nitrate in vegetables, canned food, meat products and dairy products. In the Federal Republic of Germany, the Netherlands and Belgium and other countries. Vegetables into the store with a note of the exact content of nitrate instructions. 81.5% of the nitrate ingested by the human body comes from vegetable harvesting. Therefore, the intake of nitrate is the key to evaluate the quality of vegetables. Some vegetables and melons crops, nitrate (inorganic N content, mg / kg) of the minimum and maximum content list is as follows Watermelon 10-130 Eggplant 2-60 Pumpkin 70-300