Geochemical baseline values and spatial distribution of major, trace, and rare earth elements in unpolluted soils of the Sicily region (Italy)

This study presents a comprehensive investigation of the geochemical baseline values and the spatial distribution of major, trace elements, and rare earth elements in the unpolluted soils of Sicily region. The concentrations of elements were quantified by ICP-OES and ICP-MS. The distribution patterns of major and trace elements are closely linked to the geological features of the area. The major elements Fe, Ca, Al, Mg, and K exhibit the highest concentrations. The order of abundance for trace elements follows this trend: Ba, Sr, Zn, V, Cr, Cu, Rb, Ni, Pb, B, Li, Co, As, Mo, U, Sb, Se, Cd, and Bi. Regional geochemical baseline values were calculated using the UTL95 - 95 method with BCA bootstrap, demonstrating that the regional approach provides a more accurate assessment compared to European and Italian threshold values. A geostatistical approach was used to produce spatial geochemical maps, which allow the prediction of element distributions in unsampled areas. This integrated approach establishes a benchmark for more detailed studies on environmental risk assessment, providing a solid foundation for identifying and understanding natural and anthropogenic geochemical anomalies in the soils of the Sicily region.