Nitrate in Leafy Vegetables: Toxicity and Safety Measures

Vegetables constitute a major dietary source of nitrate, contributing to the daily dietary intake for a percentage ranging from 30 to 94%. Although nitrate itself is relatively non-toxic, or even beneficial, the possible harmful effects of nitrate derived compounds on human health arouse public concern and have led to the development of government regulations and monitoring programs aimed at protecting the public health. In this perspective, have been set an acceptable daily intake for nitrates and maximum levels of nitrate content for several vegetables, paying particular attention to some leafy vegetables, characterized by a high capacity to accumulate nitrates. This chapter focuses on the main factors concerning nitrate accumulation in vegetables and their contribution to nitrate intake in the human diet, taking into account the recent EU Regulation No. 1258/2011 and the Scientific Opinion of the Panel on Contaminants in the Food chain (CONTAM) of the European Food Safety Authority (EFSA).