Agron. Sustain. Dev.
Volume 27, Number 1, January-March 2007
Page(s) 45 - 57
Published online 07 November 2006
Agron. Sustain. Dev. 27 (2007) 45-57
DOI: 10.1051/agro:2006021

Nitrate accumulation in plants, factors affecting the process, and human health implications. A review

Anjana, Shahid Umar and Muhammad Iqbal

Department of Botany, Jamia Hamdard, Hamdard Nagar, New Delhi - 110 062, India

(Accepted 21 July 2006; published online 7 November 2006)

Abstract - Leafy vegetables occupy a very important place in the human diet, but unfortunately constitute a group of foods which contributes maximally to nitrate consumption by living beings. Under excessive application of nitrogen fertilizer, these vegetables can accumulate high levels of nitrate and, upon being consumed by living beings, pose serious health hazards. Therefore, efforts are warranted to minimize the accumulation of nitrate in leafy vegetables and its ingestion by human beings. This review focuses on (i) the contribution of vegetables towards dietary nitrate intake by humans, (ii) the nutritional, environmental and physiological factors affecting nitrate accumulation in plants, (iii) the harmful and beneficial effects of nitrate on human health, and (iv) the strategies that may be followed to minimize the nitrate content in plants and its subsequent consumption by human beings. The risk to human health due to nitrate consumption may be minimized by harvesting vegetables at noon, removal of organs rich in nitrate content and cooking of vegetables in water with a low nitrate content. The European Commission Regulation No. 1822/2005 needs to be followed in order to ensure safe levels of nitrate in plants for human consumption.

Key words: nitrate toxicity / nitrate reductase / spinach / human health / leafy vegetables

Corresponding author: Shahid Umar

© INRA, EDP Sciences 2006