Study on moss biomonitoring of atmospheric deposition of minor and trace elements in the region of Polog, North Macedonia

Abstract

AbstractA study was conducted to investigate air deposition and to explore the natural or anthropogenic sources of contamination with potentially toxic elements (PTEs) in the region of Polog, North Macedonia, using moss samples as biomonitors of air pollution. The distribution of 22 elements was detected in 43 moss samples collected in the region. Multivariate statistical analysis was applied to the available data. Factor analysis identified five association factors, of which four factors, F1 (Cr, Li, V, Co, Fe, Al, Ni, and As), F2 (K, P, and Mg), F4 (Ag and Cu), and F5 (Ba, Sr, and Mn) were related to lithogenic sources and one factor F3 (Hg, Pb, Cd, and Zn) was related to mixed lithogenic and anthropogenic sources. The content of the elements of F1 is higher in the areas on Mount Šar (area without industrial and urban activities), where Precambrian and Paleozoic shales and Paleozoic sandstones predominate, indicating that their origin is mainly a natural phenomenon. The high contents of the elements from F2, F4, and F5 are also related to the lithology of the studied region. Thus, the high contents of elements from F2 are distributed in the western part of the area, where Precambrian and Paleozoic shists and Paleozoic sandstones dominate, and their contents correlate well with the contents of lithogenic elements in the soil samples from the same region. Elements of Factor 4 have higher contents in the southern part of the region, in areas with Paleozoic‐Mesozoic carbonates and Precambrian‐Paleozoic shales, while elements of Factor 5 occur in the regions with shales, Quaternary sedimentary rocks, and Precambrian‐Paleozoic shales, also indicating the lithogenic character of this factor. In addition to the lithogenic origin of the distribution of elements contained in F3 (Hg, Pb, Cd, and Zn), anthropogenic activities also have an influence on the increased content in the northeastern part of the region. This is due to dust emissions from the Silmak ferrosilicon smelter, as well as emissions from industry (steel smelters) and urban activities of the nearby capital Skopje.