In aquatic organisms, trophic transfer is a relevant exposure route for microplastics (MPs). Despite their relevance, effect studies on fish exposed via trophic chains are currently very scarce. MPs are known to contain many chemicals that could be transferred to organisms and induce deleterious effects. However, there is currently no consensus on whether MPs represent a significant exposure pathway to chemicals in contaminated habitats. Here, we exposed three-spined sticklebacks (Gasterosteus aculeatus) to polyethylene MPs via prey ingestion, in a one-month experiment. MPs were either pristine or spiked with chlorpyrifos (CPF), and a CPF control was included to§compare vector effects of MPs and natural prey. Following exposure, we assessed AChE activity and fish behavior (feeding, locomotion, environment exploration and reaction to the introduction of a novel object). No effect was observed in fish exposed to pristine MPs. CPF accumulation was observed in fish exposed to CPF-spiked MPs (MP-CPF), confirming the vector potential of MPs. However, CPF accumulation was more important in fish exposed to CPF via prey. In fish exposed to MP-CPF, we observed significant AChE inhibition and hyperactivity, which could result in increased vulnerability to predation. CPF organ distribution differed between groups, suggesting that chemical exposure via MPs could alter organ distribution of chemicals. This can result in a change in the organs most at risk, likely increasing intestine exposure.

中文翻译：

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微塑料载体效应：当通过营养链暴露时，鱼类是否处于危险之中？

在水生生物中，营养转移是微塑料 (MP) 的相关暴露途径。尽管它们具有相关性，但目前对通过营养链暴露的鱼类的影响研究非常少。众所周知，MP 含有许多化学物质，这些化学物质可以转移到生物体中并引起有害影响。然而，目前对于 MP 是否代表受污染栖息地中化学品的重要暴露途径尚无共识。在这里，我们在为期一个月的实验中通过摄入猎物将三刺棘鱼 (Gasterosteus aculeatus) 暴露于聚乙烯 MPs。MP 是原始的或掺有毒死蜱 (CPF) 的，并包含 CPF 对照以比较 MP 和天然猎物的病媒效应。暴露后，我们评估了 AChE 活性和鱼类行为（进食、运动、环境探索和对引入新物体的反应）。在暴露于原始 MP 的鱼中未观察到任何影响。在暴露于掺有 CPF 的 MP (MP-CPF) 的鱼中观察到 CPF 积累，证实了 MP 的载体潜力。然而，在通过猎物接触 CPF 的鱼中，CPF 的积累更为重要。在暴露于 MP-CPF 的鱼中，我们观察到显着的 AChE 抑制和过度活跃，这可能导致更容易被捕食。CPF 器官分布因组而异，这表明通过 MP 接触化学物质可能会改变化学物质的器官分布。这可能导致风险最大的器官发生变化，可能会增加肠道暴露。确认 MP 的矢量潜力。然而，在通过猎物接触 CPF 的鱼中，CPF 的积累更为重要。在暴露于 MP-CPF 的鱼中，我们观察到显着的 AChE 抑制和过度活跃，这可能导致更容易被捕食。CPF 器官分布因组而异，这表明通过 MP 接触化学物质可能会改变化学物质的器官分布。这可能导致风险最大的器官发生变化，可能会增加肠道暴露。确认 MP 的矢量潜力。然而，在通过猎物接触 CPF 的鱼中，CPF 的积累更为重要。在暴露于 MP-CPF 的鱼中，我们观察到显着的 AChE 抑制和过度活跃，这可能导致更容易被捕食。CPF 器官分布因组而异，这表明通过 MP 接触化学物质可能会改变化学物质的器官分布。这可能导致风险最大的器官发生变化，可能会增加肠道暴露。表明通过 MP 接触化学物质可能会改变化学物质的器官分布。这可能导致风险最大的器官发生变化，可能会增加肠道暴露。表明通过 MP 接触化学物质可能会改变化学物质的器官分布。这可能导致风险最大的器官发生变化，可能会增加肠道暴露。