Potentially toxic elements in foodcrops (Triticum aestivum L., Zea mays L.) grown on contaminated soils

Plants can uptake potentially toxic elements from the soil and accumulate them in the roots or translocate them to the aerial parts. Excessive content of these elements in edible parts can produce toxic effects and, through the food chain and food consumption, result in a potential hazard for human health. In this study soils and plants (Triticum aestivum L and Zea mays L) from a tannery district in North-East Italy were analyzed to determine the content of potentially harmful elements (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Ni, P, Pb, S, Zn and V). According to the national legislation, the area is contaminated by Cr, Ni, Cu, Zn, Cd and V. The distribution of contaminants along the soil profile shows a general tendency to metal accumulation at surface as expected for anthropogenically enriched sites. Major anthropogenic origin was detected for Cr, Ni (from industrial activities), Zn, Cu, Cd (from agriculture practices). Major nutrients (K,P and S) and some micronutrients (Cu, Zn, Mg and Mn) are easily absorbed and translocated, while other potentially toxic elements (Ca, Fe, Al, Cd, Cr, Ni, Pb and V) are not accumulated in the seeds of the two considered species. However, the two edible species proved differently able to absorb and translocate elements, and this suggests to consider separately every species as potential PHEs transporter to the food chain and to humans. Chromium concentrations in seeds and other aerial parts of the examined plants are higher than the values found for the same species and for other cereals grown on unpolluted soils. Comparing the Cr levels in edible parts with recommended dietary intake, besides other possible Cr sources (dust ingestion, water), there seems to be no health risk for animal breeding and population due to the consumption of wheat and maize grown in the area. (C) 2014 Elsevier B.V. All rights reserved.