Soil accumulation and plant uptake of pharmaceutical active compounds and related metabolites from irrigation water in fennel (Foeniculum vulgare Mill.)

Introduction: The reuse of treated wastewater (TWW) in agriculture is attracting increasing interest as a sustainable strategy to address water scarcity, particularly in arid and semi-arid regions. However, its use can pose risks due to the potential presence of emerging contaminants of concern, such as personal care products and pharmaceuticals. Methods: Mill.) with fresh water spiked with these PhACs at different concentrations (0.5, 2.0, 200, and 600 µg L⁻¹). Fennel plants were grown under controlled greenhouse conditions and analysed for PhAC content in their roots, leaves, and edible parts (bulbs). Soil and plant PhACs content were evaluated using SPE-UHPLC-HRMS/MS and the Bioconcentration (BCF) and translocation factors (TF) were also assessed. Results: Results showed PhACs accumulation in the soil and roots only at higher spiked concentrations (≥200 µg L⁻¹). Among the compounds, carbamazepine exhibited the highest root accumulation (BCF>1), but limited translocation to bulbs (TF<1). Climbazole and flecainide, despite their persistence in soil, showed low root uptake (BCF<1) and negligible translocation to bulbs. Discussion: Multivariate statistical analyses revealed compound-specific patterns governed by physicochemical properties such as ionization and hydrophobicity. Overall, fennel crop showed a restricted capacity to accumulate and translocate PhACs to bulbs, suggesting a physiological barrier that may reduce human health risks when using treated wastewater for irrigation. The results provide new insights into the environmental safety of wastewater reuse, with a specific focus on its impact on crop yield, highlighting the need for crop-specific assessments.