Co-existence of microplastics, nanomaterials, and antibiotics may lead to intensified multifaceted pollution, which may influence their fate in soils. This study investigated the co-transport behavior of polystyrene microplastics (PS) and compound pollutants of graphene oxide (GO) and tetracycline (TC). Packed column experiments for microplastic with or without combined pollutants were performed in KCl (10 and 30 mM) and CaCl₂ solutions (0.3 and 1 mM). The results showed transport of PS was facilitated at low ionic strengths and inhibited at high ionic strengths by GO with or without TC under examined conditions. Carrier effect of GO as well as the aggregation of PS in the presence of co-exiting GO or GO-TC could be the contributor. Although the existence of TC relieved the ripening phenomenon of PS and GO deposition due to enhanced electronegativity of sand media, the effect of GO on the PS transport has not been significantly impacted, indicating the dominant role of GO during cotransport process. Furthermore, the transport of PS was increased by TC owing to competition for deposition sites on sand surfaces. In turn, the transport of TC was mainly affected by PS whether graphene was present or not. The increase in electrostatic repulsive force (transport-promoting) and addition adsorption sites (transport-inhibiting) may be responsible for the observations. Our findings could improve understandings of complex environmental behaviors of microplastics and provide insight into investigation on cotransport of emerging contaminants under various conditions relevant to the subsurface environment.

微塑料、纳米材料和抗生素的共存可能会导致多方面污染加剧，从而影响它们在土壤中的命运。本研究研究了聚苯乙烯微塑料（PS）与氧化石墨烯（GO）和四环素（TC）复合污染物的共迁移行为。_{在 KCl（10 和 30 mM）和 CaCl 2}溶液（0.3 和 1 mM）中进行了含有或不含组合污染物的微塑料的填充柱实验。结果表明，在检测条件下，有或没有 TC 的情况下，GO 会在低离子强度下促进 PS 的运输，在高离子强度下会抑制 PS 的运输。GO 的载体效应以及共存 GO 或 GO-TC 下 PS 的聚集可能是促成因素。尽管TC的存在缓解了砂介质电负性增强导致的PS和GO沉积的成熟现象，但GO对PS传输的影响并未受到显着影响，表明GO在共传输过程中起主导作用。此外，由于沙子表面沉积位点的竞争，TC 增加了 PS 的传输。反过来，无论石墨烯是否存在，TC 的运输主要受 PS 的影响。静电排斥力（促进传输）和附加吸附位点（抑制传输）的增加可能是造成观察结果的原因。我们的研究结果可以增进对微塑料复杂环境行为的理解，并为在与地下环境相关的各种条件下新兴污染物的共转运研究提供见解。