Health risk assessment of metals transfer from soil to the edible part of some vegetables grown in Patuakhali province of Bangladesh

This study was conducted to investigate the contamination and chemical speciation of six heavy metals like Cr, Ni, Cu, As, Cd and Pb in soil, their transfer to the edible parts of vegetables i.e. Brinjal (Solanum melongena), Green amaranth (Amaranthus hybridus), Red amaranth (Amaranthus Gangeticus), Bottle gourd (Lagenaria siceraria), Tomato (Solanum lycopersicum), Pumpkin (Cucurbita maxima), Chili (Capsicum annuum L), Carrot (Daucus carota), Bean (Phaseolus vulgaris), Onion (Allium cepa), Potato (Solanum tuberosum) and Lentil (Lens culinaris). The ranges of heavy metals in soil were 3.7-41, 3.9-36, 7.6-46, 2.3-26, 0.61-13 and 4.5-32 mg/kg for Cr, Ni, Cu, As, Cd and Pb, respectively. The metals were mainly associated with the residual fractions of 39%, 41%, 40%, 40%, 34% and 41% for Cr, Ni, Cu, As, Cd and Pb, respectively. In the edible tissues of vegetables, the concentrations of As, Cd and Pb in most vegetable samples exceeded the maximum permissible levels, indicating not safe for human consumption. Target hazard index (HI) value indicates people would experience health risk due to consumption of vegetables. The carcinogenic risk (TR) of As and Pb through consumption of vegetables were higher than the USEPA threshold level (10−6), indicating potential cancer risks.