Concentration and health risk assessment of nitrates in vegetables from conventional and organic farming

The aims of the study were to determine: (1) nitrates concentrations in vegetables from conventional and organic farming and (2) potential health risk assessment relating to vegetables containing nitrates. The analyses were made on the 27 types of vegetables. The nitrates concentrations were determined by the potentiometric method with the CyberScan ION 510 ionometer. The highest nitrates concentrations were found for lettuce, both from conventional and organic farming. The root and bulb vegetables (potato, carrot, parsley root, radish, celery root) from conventional farming had higher nitrates concentrations than those from organic farming. For leafy vegetables (beet leaves, broccoli, chive from onion, kale, dill, lettuce, celery leaves, chive, spinach), nitrates concentrations were higher in case of organic than conventional farming. Total daily nitrates intake in vegetables from conventional farming was equal to 1.45 mg NO₃ kg^?1 bw day^?1, which is 39.2% of the acceptable daily intake (ADI), and for organic farming, it was equal to 1.91 mg NO₃ kg^?1 bw day^?1 (28.5% ADI). Health risk from vegetables containing nitrates consumption was low, both for organic (HI_O = 0.66) and conventional (HI_C = 0.86) farming. However, in case of the organic farming, this value was approaching the limit of the acceptable risk value.