Due to the hydrophobicity and large specific surface area microplastics (MPs) have become the vector for the migration of environmental organic pollutants. Environmental aging process affects the physiochemical structure of MPs and their corresponding environmental behaviors, in which the effect of bisphenol A (BPA) binding mode within plastic matrix on aging behaviors of MPs is not reported. In this work, the structural properties and BPA sorption behaviors of low density polyethylene (LDPE) MPs with BPA additives and polycarbonate (PC) MPs with BPA monomers exposed to three types of artificial accelerated aging processes including UV/H₂O, UV/H₂O₂, and UV/Cl₂ systems were comparatively investigated. Virgin LDPE and PC exhibited obvious leakage of BPA additives or monomers. Aged LDPE had stronger sorption ability towards BPA in water environment with no observed leakage of BPA additives. While, aged PC had extremely high leakage of BPA monomers, which is similar to virgin PCs and was proved to be a persistent source of BPA release. The BPA sorption on aged LDPE or leaching from aged PC was influenced by aging processes, water pH, salinity, co-existing estradiol (E2), and water sources. This study reveals the potential ecological and environmental risks of MPs containing toxic additives/monomers during aging processes from a new perspective.

由于疏水性和大的比表面积，微塑料（MPs）已成为环境有机污染物迁移的媒介。环境老化过程会影响MPs的理化结构及其相应的环境行为，但尚未报道塑料基质中双酚A（BPA）结合方式对MPs老化行为的影响。在这项工作中，具有BPA添加剂的低密度聚乙烯（LDPE）MP和具有BPA单体的聚碳酸酯（PC）MP的结构特性和BPA吸附行为暴露于三种类型的人工加速老化过程，包括UV / H ₂ O，UV / H ₂ O ₂和UV / Cl ₂系统进行了比较研究。原始LDPE和PC表现出明显的BPA添加剂或单体泄漏。老化的LDPE在水环境中对BPA的吸附能力更强，没有观察到BPA添加剂的泄漏。而老化的PC的BPA单体泄漏极高，这与原始PC相似，并且被证明是BPA释放的持续来源。BPA在老化的LDPE上的吸附或从老化的PC浸出的过程受老化过程，水的pH值，盐度，雌二醇（E2）共存和水源的影响。这项研究从新的角度揭示了老化过程中含有有毒添加剂/单体的MP的潜在生态和环境风险。