College of New Energy and Environment, Jilin University, Changchun 130012, China.
MOE Key Laboratory of Resources and Environmental Systems Optimization, North China Electric Power University, Beijing 102206, China.
J Hazard Mater. 2024 Oct 5;478:135524. doi: 10.1016/j.jhazmat.2024.135524. Epub 2024 Aug 14.
The combined pollution of polycyclic aromatic hydrocarbons (PAHs) and organic cadmium (Cd) in farmland soils, and the field controlling strategy need to be studied urgently. In this study, 5 PAHs, 5 Cd and 11 soil conditioners were selected to explore the co-exposure risk and remediation efficiency. Firstly, a significant combination Fl-alkylalkoxy cadmium was obtained using forward and reverse methods coupling variation coefficient methods (the combined pollution value was 0.173). Secondly, the interaction energy of microbial degradation / plant absorption of Fl under Cd stress, and microbial mineralization / plant absorption of alkylalkoxy cadmium under PAHs stress were characterized using factorial experimental design, molecular docking and molecular dynamics simulation. The combined pollution of alkylalkoxy cadmium and dialkyl cadmium, phenanthrene and Benzo [a] pyrene was significant (synergistic contribution rates were 17.58 % and 19.22 %, respectively). In addition, 6 soil conditioners with significant efficiency were selected to design Taguchi orthogonal experimental schemes, indicating the microbial degradation / mineralization and plant absorption were significantly effective (the maximum increase of remediation efficiency was 93.81 %) under the combinations (i.e., trratone, coumarol, fulvamic acid, potassium fertilizer and others, etc.). Finally, it was found that the soil conditioners affected the hydrophobic groups and forces, and the efficiency was proportional to the highest peak value and minimum distance in the RDF curve. This study identifies the risk characteristics of co-exposure of PAHs and Cd and screens effective soil conditioners, providing theoretical guidance for risk controlling.
农田土壤中多环芳烃（PAHs）和有机镉（Cd）的复合污染及其田间控制策略亟待研究。本研究选取 5 种 PAHs、5 种 Cd 和 11 种土壤调理剂，探索其复合暴露风险和修复效率。首先，采用正向和反向方法结合变异系数法，得到了显著的 Fl-烷氧基镉复合（组合污染值为 0.173）。其次，利用析因实验设计、分子对接和分子动力学模拟，研究了 Cd 胁迫下 Fl 微生物降解/植物吸收、PAHs 胁迫下烷基烷氧基镉微生物矿化/植物吸收的相互作用能。烷基烷氧基镉和二烷基镉、菲和苯并[a]芘的复合污染具有显著的协同作用（协同贡献率分别为 17.58%和 19.22%）。此外，选取 6 种修复效率显著的土壤调理剂，设计 Taguchi 正交实验方案，表明在组合条件下（如曲通、香豆素、富马酸、钾肥等），微生物降解/矿化和植物吸收具有显著的效果（修复效率的最大增幅为 93.81%）。最后，发现土壤调理剂影响了疏水基团和力，效率与 RDF 曲线的最高峰和最小距离成正比。本研究鉴定了 PAHs 和 Cd 复合暴露的风险特征，并筛选出有效的土壤调理剂，为风险控制提供了理论指导。
