The Nitrate Content of Commonly Consumed Agricultural Products Including Vegetables, Cereals, and Legumes in Iran

Document Type : Original Article

Authors

1 Halal research center of IRI, F.D.A., Iran

2 Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, Shahre-Kord University, Shahre-Kord, Iran

3 Food and Drug Administration (F.D.A.), Tehran, Iran

4 Social Determinants of Health Research Center, Department of Public Health, Faculty of Health, Birjand University of Medical Sciences, Birjand, Iran

5 Department of Environmental Health, Food Safety Division, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran

Abstract

The excessive presence of nitrate in foodstuff can be potentially toxic and carcinogenic to humans. This is because about 80% of the nitrate that enters the human body comes from vegetables. Therefore, the present study determined the nitrate content in agricultural products commonly consumed by Iranians. A total of 222 samples of 19 different varieties of these products, including vegetables (171 samples), cereals (42 samples), and legumes (9 samples), were randomly collected from major grocery stores in different cities in Iran between September 22 and December 15, 2020. The methods of HPLC-UV were used to evaluate the nitrate content. The detection limits (L.O.D.) and limit of quantification (L.O.Q.) were 0.071 and 0.22 mg kg-1, respectively. As a result, the mean nitrate levels in the different samples varied from 1042.50 mg kg-1 in lettuce to 49.90 mg kg-1 in wheat. Potato also had a higher mean nitrate concentration than the standard level. In addition, products such as tomatoes, eggplant, spinach, herbs, and lettuce had significantly lower average nitrate concentrations than the typical values. Moreover, the average nitrate concentration was highest in the central region (492.7 mg kg-1). In contrast, the lowest average nitrate concentration was in the northern region (121.7 mg kg-1) (P < 0.05). Moreover, the highest average nitrate concentration (468.52 mg kg-1) was found in the vegetable group and the lowest in the cereal group (50.40 mg kg-1) (P < 0.05). Taken together, this information could allow the establishment of a database for the quantification of nitrate exposure and its risk-benefit determination in the Iranian population.

Keywords


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Volume 12, Issue 2
June 2022
Pages 293-303
  • Receive Date: 02 August 2021
  • Revise Date: 01 October 2021
  • Accept Date: 05 February 2022
  • First Publish Date: 05 February 2022