College of Life Science and Technology, Jinan University, Guangzhou 510632, China.
Department of Mathematics, College of Information Science and Technology, Jinan University, Guangzhou, Guangdong 510632, China.
J Hazard Mater. 2024 Dec 5;480:135770. doi: 10.1016/j.jhazmat.2024.135770. Epub 2024 Sep 12.
Polystyrene microplastics (PS) and dibutyl phthalate (DBP) are emerging pollutants widely coexisting in agroecosystems. However, the efficacies of PS as carriers for DBP and their interactive mechanisms on crop safety remain scarce. Here, this study investigated the combined exposure effects and the interacting mechanisms of PS laden with DBP on choy sum (Brassica parachinensis L.). Results showed that PS could efficiently adsorb and carry DBP, with a maximum carrying capacity of 9.91 %, facilitating the chemical translocation of DBP in choy sum and exacerbating phytotoxicity. Due to the changes in the properties of PS, DBP loading aggravated the phytotoxicity of choy sum, exhibiting synergistically toxic effects compared with individual exposure. The Trojan-horse-complexes formed by PS+DBP severely delayed the seed germination process and altered spatial growth patterns, causing disruptions in oxidative stress, osmoregulation, photosynthetic function, and elemental reservoirs of choy sum. Combined pollutants enhanced the uptake and translocation of both PS and DBP by 8.90-31.94 % and 136.81-139.37 %, respectively; while the accumulation processes for PS were more complex than for DBP. Visualization indicated that PS was intensively sequestered in roots with a strong fluorescent signal after loading DBP. This study comprehensively investigated the efficacies of PS carrying DBP on phytotoxicity, bioavailability, and their interactive mechanisms, providing significant evidence for food safety assessment of emerging contaminant interactions.
聚苯乙烯微塑料（PS）和邻苯二甲酸二丁酯（DBP）是广泛存在于农业生态系统中的新兴污染物。然而，PS 作为 DBP 的载体的效果及其对作物安全的相互作用机制仍然很少。在这里，本研究调查了负载 DBP 的 PS 对白菜（ Brassica parachinensis L.）的联合暴露效应及其相互作用机制。结果表明，PS 可以有效地吸附和携带 DBP，最大携带能力为 9.91%，促进了 DBP 在白菜中的化学迁移，并加重了植物毒性。由于 PS 性质的变化，DBP 负载加重了白菜的植物毒性，与单独暴露相比表现出协同毒性效应。PS+DBP 形成的特洛伊木马复合物严重延迟了种子发芽过程，并改变了空间生长模式，导致白菜的氧化应激、渗透调节、光合作用功能和元素库受到干扰。复合污染物使 PS 和 DBP 的吸收和迁移分别增加了 8.90-31.94%和 136.81-139.37%；而 PS 的积累过程比 DBP 更为复杂。可视化表明，负载 DBP 后，PS 被强烈荧光信号强烈隔离在根部。本研究全面调查了 PS 携带 DBP 对植物毒性、生物利用度及其相互作用机制的效果，为新兴污染物相互作用的食品安全评估提供了重要证据。
