The contents of the potentially harmful elements in the arable soils of southern Poland, with the assessment of ecological and health risks: a case study

Agricultural soil samples were collected from the areas where edible plants had been cultivated in southern Poland. The PHE content decreased in proportion to the median value specified in brackets (mg/kg d.m.) as follows: Zn (192) > Pb (47.1) > Cr (19.6) > Cu (18.8) > Ni (9.91) > As (5.73) > Co (4.63) > Sb (0.85) > Tl (0.04) > Cd (0.03) > Hg (0.001) > Se (< LOQ). No PHE concentrations exceeded the permissible levels defined in the Polish law. The PHE solubility (extracted with CaCl₂) in the total concentration ranged in the following order: Fe (3.3%) > Cd (2.50%) > Ni (0.75%) > Zn (0.48%) > Cu (0.19%) > Pb (0.10%) > Cr (0.03%). The soil contamination indices revealed moderate contamination with Zn, ranging from uncontaminated to moderately contaminated with Pb, and, practically, no contamination with other PHEs was identified. The ecological risk indices revealed that soils ranged from uncontaminated to slightly contaminated with Zn, Pb, As, Cu, and Ni. The PCA indicated natural sources of origin of Co, Cu, Hg, Sb, Zn, Cr, and Pb, as well as anthropogenic sources of origin of Cd, Ni, As, and Tl. The human health risk assessment (HHRA) for adults and children decreased in the following order of exposure pathways: ingestion > dermal contact > inhalation of soil particles. The total carcinogenic risk values for both adults and children were at the acceptable level under residential (1.62E-05 and 6.39E-05) and recreational scenario (5.41E-06 and 2.46E-05), respectively, as well as for adults in agricultural scenario (1.45E-05). The total non-carcinogenic risk values for both adults and children under residential scenario (1.63E-01 and 4.55E-01, respectively), under recreational scenario (2.88E-01 and 6.69E-01, respectively) and for adults (1.03E-01) under agricultural scenario indicated that adverse health effects were not likely to be observed. Investigated soils were fully suitable for edible plant cultivation.