We present a generic theoretical model (MICROWEB) that simulates the transfer of microplastics and hydrophobic organic chemicals (HOC) in food webs. We implemented the model for an Arctic case comprised of nine species including Atlantic cod and polar bear as top predator. We used the model to examine the effect of plastic ingestion on trophic transfer of microplastics and persistent HOCs (PCBs) and metabolizable HOCs (PAHs), spanning a wide range of hydrophobicities. In a scenario where HOCs in plastic and water are in equilibrium, PCBs biomagnify less when more microplastic is ingested, because PCBs biomagnify less well from ingested plastic than from regular food. In contrast, PAHs biomagnify more when more microplastic is ingested, because plastic reduces the fraction of PAHs available for metabolization. We also explore nonequilibrium scenarios representative of additives that are leaching out, as well as sorbing HOCs, quantitatively showing how the above trends are strengthened and weakened, respectively. The observed patterns were not very sensitive to modifications in the structure of the food web. The model can be used as a tool to assess prospective risks of exposure to microplastics and complex HOC mixtures for any food web, including those with relevance for human health.

中文翻译：

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水生食物网中塑料碎片和相关污染物的积累。

我们提出了一个通用的理论模型（MICROWEB），该模型可模拟食物网中微塑料和疏水性有机化学品（HOC）的转移。我们为北极案例实施了该模型，该案例由九种物种组成，其中包括大西洋鳕和北极熊作为最大的捕食者。我们使用该模型检查了塑料摄入对微量塑料和持久性HOC（PCBs）和可代谢HOC（PAHs）的营养转移的影响，涉及范围广泛的疏水性。在塑料和水中的HOC处于平衡状态的情况下，如果摄入更多的微塑料，则PCB的生物放大率会降低，因为摄入的塑料中PCB的生物放大率要比普通食品低。相反，当摄入更多的微塑料时，PAH的生物放大作用更大，因为塑料会减少可用于代谢的PAH的比例。我们还探索了代表正在浸出的添加剂以及吸附HOC的非平衡场景，定量地显示了上述趋势如何分别增强和减弱。观察到的图案对食物网结构的改变不是很敏感。该模型可用作评估任何食物网（包括与人类健康相关的食物）暴露于微塑料和复杂HOC混合物中的潜在风险的工具。