Potentially Toxic Elements in Serpentinite-Derived Soils and Dittrichia viscosa from Southern Italy: A Preliminary Descriptive Assessment

Serpentinite-derived soils are naturally enriched in potentially toxic elements (PTEs) and may represent an environmental concern where asbestos-bearing lithologies occur at the surface. The Gimigliano–Monte Reventino Unit (Calabria, southern Italy) hosts serpentinite outcrops containing fibrous and non-fibrous minerals associated with elevated PTE concentrations. This study provides a preliminary descriptive assessment of six soil–plant pairs, comprising five serpentinite locations and one non-serpentinite reference location, to examine PTE concentrations in soils and in roots and shoots of the Mediterranean species D. viscosa. Total concentrations of V, Cr, Co, Ni, Cu, Zn, and Cd were determined by inductively coupled plasma mass spectrometry following acid digestion. Soils from the five serpentinite locations showed higher concentrations of Cr, Ni, Co, and V than the reference soil, exceeding the Italian regulatory thresholds for agricultural land use. Several soil Cr and Ni concentrations exceeded 1000 mg kg−1. Plant elemental concentrations and root–shoot partitioning varied markedly among the sampled individuals. The MRL individual exhibited particularly elevated Cr and Ni concentrations in shoots. Compartment-specific bioconcentration factors were generally below unity where quantitatively evaluable. These paired observations document contrasting elemental concentration patterns in D. viscosa growing on naturally enriched substrates. Given the single soil–plant pair collected per location and the analytical limitations associated with concentrations exceeding the calibration range, the findings remain exploratory and support further replicated investigations of element uptake and partitioning rather than conclusions about location effects or vegetation-based management performance.