We studied the uptake of Cr and Ni to edible parts of different groups of vegetables grown in areas with increased geogenic or anthropogenic origin in the soil. We selected a smaller sampling area in Vrhnika, where the Cr concentrations in soil are in median 117 mg/kg (2 samples), as a result of anthropogenic sources, and a larger sampling area in Slovenian Istria, where the soil contains increased concentrations of Cr (median 51.4 mg/kg; 13 samples) and Ni (median 75.1 mg/kg; 13 samples) of geogenic origin. The Cr concentrations in vegetables from Vrhnika (17 samples) ranged from 3.7 µg/kg fresh weight in cucumbers to 521.6 µg/kg f.w.in thyme, for all samples in avg. 262.6 (µg/kg f.w.). The Cr and Ni concentrations in the vegetables from Slovenian Istria (53 samples) averaged 69.1 µg/kg f.w. and 142.9 µg/kg f.w. for Cr and Ni, respectively. In Slovenian Istria, the highest Cr and Ni concentrations were in garlic (240.6 µg/kg f.w.) and parsley (636.3 µg/kg f. w.) respectively, the lowest Cr and Ni concentrations were in cucumbers (3.7 and 45.51 µg/kg f.w., respectively). We estimated the chronic exposure of general population to Cr and Ni due to the consumption of vegetables produced in Slovenian Istria, which took into account consumption of vegetables in Slovenian households for 2015 and avg. concentrations of Cr and Ni in the vegetables (µg/kg f.w.). The assessed value of exposure to Cr (0.152µg/kg b.w./day) and Ni (0.469 µg/kg b.w./day) with vegetables from Slovenian Istra, including tubers, legumes, herbs and mushrooms was compared to the calculated exposure with average European vegetables (exposure to Cr 0.206 and Ni 0.612 µg/kg b.w./day) based on Slovenian data for vegetable consumption. Data from an extensive study in Celje, which served as a control area for Ni content in selected vegetables, showed four times lower concentrations of Ni in comparison to vegetables from Slovenian Istria. Increased levels of Cr and Ni in the soil affect the content of Cr and Ni in vegetables, but the concentrations are not higher than in average European vegetables. In addition to Ni concentrations in soil, the uptake of Ni in plants is also significantly affected by organic matter (OS) and pH.
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