Trace elements in soils and food chains of the Balkan region

The present review summarizes the available data on the concentration of trace elements (TEs) in soils and their availability to plants with a view to reflect the quality and safety of food and fodder crops. Most soils in western Balkan countries are not contaminated. However, soils around industrial centers and historical mining sites do create concern for food and feed safety. Also high concentrations of TEs are related to their geochemical original. For example, ultrabasic rocks and serpentinites in western Serbia and western Bosnia are very rich in chromium, nickel, magnesium, iron (Fe), and cobalt, and cover an area of 5200 km(2). High TE concentrations caused by anthropogenic activities are also reported. In vineyard soils in Croatia, concentrations of cadmium, copper (Cu), and zinc (Zn) were much higher than their background concentrations. On the other hand, TE deficiency in plants is also prevalent in the regions. For example, Zn and Fe deficiencies in eastern parts of Croatia and northern parts of Serbia, Cu deficiency in pasture and sheep's blood at Nisici Plateau of Bosnia and Herzegovina, and selenium (Se) deficiency almost in the whole region have been observed. Therefore, information on TEs' behavior and soil factors affecting their mobility and availability is highly needed in order to separate the areas of contamination and then propose agrotechnical measures to protect the entry of TEs into the food chain. Research is also required to assess the influence of agronomic management on TE supply to plants and for achieving a better utilization of essential TEs. Concentrations of Se in wheat in Serbia are so low that if people were fed exclusively with wheat, their daily requirements for Se would not be met. There is also a need for full implementation of new food safety regulations in the Balkan countries in accordance with the legislations of the European Union.