Assessment of Pb, Zn, Cu, Ni and Cr in vegetables grown around Zanjan Province

This study was conducted aimed to assess the potential risk of heavy metals on human health resulting from consumption of vegetables. To this end, the vegetables grown around town and industrial center of Zanjan were sampled randomly. Plant samples were digested using hydrochloric acid (HCL) 2 M and concentration of elements (Pb, Zn, Cu, Ni and Cr) were recorded by atomic absorption. Obtained means of heavy metals in all vegetables (N= 32) for Zn, Pb, Cu, Ni and Cr is 98.8, 31.9, 19.3, 4.4 and 2.3 mg/kg, respectively. The highest amount of metal pollution index (MPI) in the basil and the lowest was observed in the garden cress (respectively 16.46 and 4.88). Daily intake (EDI) for zinc, copper and chromium in all age groups was lower than the provisional tolerable daily intake (PTDI). This amount for nickel was 2, 1.6 and 1.3 %, and for Pb 28.1, 22 and 19 % higher than PTDI in children, adults and seniors, respectively. The potential risk (THQ) was calculated in all age groups as Pb>>Cu>Zn>Ni>Cr. The potential risks (THQ) of chromium, nickel and zinc were calculated lower than 1, for copper a bit more of 1 and for lead much higher than 1. Health index (HI) for children, adults and the elderly was estimated 31.331, 24.58 and 21.14, respectively, with the largest contribution of the lead (89.7%)