Abstract
In this study, nitrate and nitrite contents were determined of a total (308) samples of 15 different types of vegetable such as leek, swiss chard, celery, spinach, garden cress, green onion, turnip, radish, aubergine, squash, tomato, pepper, cucumber, mint, and tarragon. They were taken from different fields located in Sulaymaniyah province: Sulaymaniyah city (Tanjarro and Kanaswra), Bazyan (Baynjan), Halabja (Said Sadiq), and Kalar (Grda Gozena). Using spectrophotometer measurements performed by UV/VIS double beam spectrophotometer at 538nm. The highest level of nitrate (529.55 mg/kg) for garden cress in Said Sadiq, (486.74 mg/kg) for Swiss chard in Kanaswra, and (477.65 mg/kg) for spinach in Bazyan. In addition, leek and celery contained high nitrate concentrations of about (416.65 and 447.60) mg/kg in Kanaswra and Bazyan, respectively. While the lowest nitrate concentration in fruiting vegetables like a tomato was 5.934 mg/kg in Bazyan, and aubergine in Grda Gozena was 5.617 mg/kg. Interestingly, the value of the Acceptable Daily Intake (ADI) and the Target Hazard Quotient (THQ) was lower than the standard limit, ADI for nitrate in this study was about (0.51, 2.18) mg/kg bw/day for adults and children, while the standard limit (3.70 mg/kg bw/day). Also, ADI for nitrite in this study was about (0.01, 0.05) mg/kg/bw for adults and children, while the standard limit was about 0 - 0.06 mg kg, as a result, the THQ ≤1. In summary, we can conclude that the amount of nitrates in raw vegetables was lower than the standard limit’s level and that this level does not cause health problems for consumers.