Spatial distribution and pollution assessment of heavy metals in soil from the Republic of North Macedonia

The purpose of the study was to determine the spatial distribution and pollution assessment of 39 chemical elements in soil from the Republic of North Macedonia. From the whole territory of the country top soil samples (0-30 cm) were collected from 995 locations with a grid of 5 x 5 km distance between the sampling locations. Two analytical techniques were used for the analysis of soil samples: inductively coupled plasma-atomic emission spectrometry and inductively coupled plasma-mass spectrometry. Based on a comparison of statistical parameters, spatial distribution of particular elements and results of cluster and factor analysis, four main geochemical associations were identified: (1) association connected with the Neogene and Quaternary volcanism (Ba, Be, Ce, Hf, K, La, Rb, Th, Tl, U and Zr); (2) association of siderophile elements (Co, Cu, Fe, Mn, Sc, Ti and V); (3) association connected with ophiolites and Mesozoic ultrabasic magmatic rocks of Vardar zone (Cr and Ni) and (4) chalcophile (sulphide) elements (As, Bi, Cd, Pb, Sb, Sn and Zn). The regional distribution was prepared according to the eight statistical regions in Macedonia, distribution according to 15 most common geological formation and distribution according to 13 pedological units.