Heavy metals in soil, grape, and wine

The elemental concentrations of nine elements (V, Cr, Mn, Fe, Ni, Cu, Zn, As and Pb) were determined in soil, grape and wine samples taken from the wine producing area of Vrbnik on the island Krk in the northern Adriatic) using the tube excited energy dispersive X-ray fluorescence, EDXRF method. Extensive grape cultivation in Vrbnicko polje through the years approximately doubled the Cu content in the soil from this area compared to the background level determined on Krk. Most of this total Cu is exchangeable and thus available to plants. The concentrations of all other elements are similar to those found in the Krk soil. Canonical analysis showed that the main source of heavy metals in grape was absorption from the soil. Statistically significant differences in elemental composition between red and white wine were found. All elements showed greater concentrations in red grape. In spite of the elevated Cu level in the soil, the content of this metal in wine was much lower than the allowed value.