Factors conditioning soil PTE contents and the associated health risk in an area with mixed land use.

Abstract

The study of soil chemical composition and geochemical characterization is of great concern. In 2020, a soil survey of the Ararat region (Armenia) was conducted to study the contents of soil elements (Cr, V, Ti, As, Zn, Cu, Co, Fe, Mn, Ba, Pb, Mo, Ca, and K), identify pollution sources and factors conditioning their spatial distribution patterns, and assess the health risk associated with potentially toxic elements (PTEs). The combined application of compositional data analysis and geospatial mapping allowed to reveal three subsamples with unique chemical signatures. Group I included soils in which Fe, Co, Ti, Mn, V, Ba, Pb, and Zn had mainly a natural origin. Soils of Group II are localized in heavily urbanized and industrialized parts of the region, and their spatial distribution is in line with relatively high contents of Cu and partially As, Cr, and K. The spatial distribution of Group III coincides with positions of soils with relatively high contents of Ca and is in line with the geological features and the locations of stone quarries. The human health risk assessment showed that As contents pose a mono-elemental noncarcinogenic health risk to children in two sites (near the Gold Factory and Tigranashen village), whereas a multi-elemental health risk to children was identified on almost the entire region's territory. Moreover, the comparatively high level of As risk was identified in Group III and linked to the travertine quarries exploitation. The results of this study indicated the need for additional in-depth studies targeting As contents and its unrevealed features linked to the travertine quarries exploitation.