Maize (Zea mays L.) Plants Alter the Fate and Accumulate Nonextractable Residues of Sulfamethoxazole in Farmland Soil

• DOI: 10.1021/acs.est.3c08954
• Publication Date: 2024-05-16T11:04:43Z
• Authors: Xuan Wu; Feifei Sun; Siqi Cao; Qilin Wang; Lianhong Wang; Songfeng Wang; Yan He; Boris Alexander K...; Philippe Francois...; Rong Ji
• Keywords: Soil; Farms; Sulfamethoxazole; Soil Pollutants; Zea mays

The fate of sulfonamide antibiotics in farmlands is crucial for food and ecological safety, yet it remains unclear. We used [phenyl-U-14C]-labeled sulfamethoxazole (14C-SMX) to quantitatively investigate the SMX a soil–maize system 60 days, based on six-pool model. Formation nonextractable residues (NERs) was predominant unplanted soil, accompanied by minor mineralization. Notably, maize plants significantly increased dissipation (kinetic constant kd = 0.30 day–1 vs 0.17 day–1), while substantially reducing NER formation (92% 58% initially applied SMX) accumulating (40%, mostly bound roots). Significant NERs (maximal 29–42%) were formed via physicochemical entrapment (determined using silylation), which could partially be released taken up plants. consisted considerable amount (1–8%) alkali-hydrolyzable covalent bonds (2–12%, possibly amide linkage). Six 10 transformation products quantified soil extracts NERs, respectively, including hydroxyl substitution, deamination, N-acylation, among N-lactylated found first time. Our findings reveal composition instability SMX-derived soil–plant underscore need study long-term impacts reversible NERs.