Assessment of Molybdenum, Arsenic, and Selenium Bioaccumulation in Medicinal Plants: Implications for Human Health Across Diverse Agro-Ecological Zones

This study evaluated the concentration, mobility, and plant uptake of three trace elements, Molybdenum (Mo), Arsenic (As), and Selenium (Se) in soils and selected medicinal plants across two locations and eight different sites. Mo concentrations in soil were below the critical threshold (1 mg/kg), but plant Mo levels above safe limits (>6 mg/kg), particularly in Calotropisgigantea and Cannabis sativa, indicating a risk of bioaccumulation. Arsenic levels in soil were safe (<20 mg/kg), but most plants above the WHO’s allowed limit for therapeutic use (1.0 mg/kg), with Menthaspicata and C. sativa having the highest levels. Selenium concentrations in soils and plants ranged within or just over safe levels, with C. gigantea accumulating the most Se. Bio-concentration factors (BCFs) varied greatly, indicating differential absorption capability among species. All soil-to-plant transfer linkages were found to be weak or non-significant using correlation analysis. These findings suggest potential elemental risks associated with medicinal plant consumption and highlight the need for site-specific monitoring and metal management strategies in plant-based therapeutic applications.