Several researchers recognize the importance of plants as effective tools for environmental biomonitoring. The black poplar (Populus nigra L.) often emerges as a useful bioindicator of air quality in urban environments, where this tree species is widely employed for urban areas. Here, we used ICP-MS analysis to assess the presence and concentration of trace elements, with a special focus on heavy metals (HMs), in black poplar leaves and soil samples from three urbanized sites showing varying degrees of environmental quality. Specifically, the foliar concentrations of Zn (173.3 ppm), Cd (0.7 ppm), Co (1.1 ppm) and As (0.2 ppm) exceeded reference values for unpolluted sites, indicating potential environmental hazards. Additionally, we correlated the foliar concentrations of HMs with those quantified in soil and with air quality data provided by the regional air quality-monitoring network. Subsequently, we estimated the values of foliar fluctuating asymmetry, and evaluated their relationships with HM concentrations in both leaves and soil. Our results suggest that element concentrations in black poplar leaves are related to soil contamination and atmospheric quality, and the extent depends on the proximity to relevant pollution sources. Furthermore, the study species showed a pronounced accumulation capacity for some HMs (i.e., Zn, Cd) commonly found in particulate matter. The extent of foliar fluctuating asymmetry is related to atmospheric quality and HM soil concentration, possibly because of the growth anomalies induced by this kind of environmental contamination. Overall, our data indicate the study species can supply an effective biomonitoring service in urbanized contexts, offering valuable insights into the occurrence and biological implications of heavy metal contamination.

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.