Interactions Between Cadmium Contamination and Mineral Sorbents in Shaping Heavy Metal Bioaccumulation in Soil and Plant Biomass

By disrupting soil ecosystem functioning, cadmium threatens food safety. Therefore, a significant research imperative is to develop effective remediation strategies and understand the relationships between cadmium content in soil and plants and the content of other metals. This study aimed to evaluate the effects of calcium carbonate, sepiolite, expanded clay, zeolite, and molecular sieve on the growth and physiological response of Zea mays grown in cadmium-contaminated soil. Plant growth and development were assessed together with the translocation and bioaccumulation of cadmium and other metals (Pb, Cr, Cu, Zn, Fe, Ni, and Mn) and changes in soil physicochemical properties. The study was conducted as a pot experiment using uncontaminated soil and soil contaminated with 15 and 30 mg Cd kg−1. Depending on the contamination level, cadmium reduced the leaf greenness index of Zea mays by 10–16%, the yield of the aboveground parts by 60–76%, and root yield by 60–69%. The tested sorbents modified these responses mainly by altering the soil physicochemical properties. The molecular sieve was the most effective, reducing the negative effect of cadmium on the yield of the aboveground parts and roots by an average of 31% while not significantly affecting the leaf greenness index. Cadmium increased the translocation factor of all analyzed elements except cadmium itself, indicating its potential to affect the homeostasis of other elements in the plant. Heavy metal bioaccumulation in the roots of Zea mays was significantly greater than in the aboveground parts. Cadmium altered the bioaccumulation of individual elements to different extents, but these effects could be modified through the appropriate selection of mineral sorbents. These findings make an important contribution to the development of effective methods for remediating cadmium-contaminated soils.