Abstract：
Microplastic particles appear in great abundance and variety in freshwater ecosystems across the globe, spanning lakes and rivers, with increasingly frequent exposure of aquatic organisms. Studies on the mechanisms of any effects of plastic particles are still scarce, particularly in relation to the regenerative capacity of biota, for which there is no established model organism; however, planaria have shown sensitivity for assessing these risks to the aquatic environment. Thus, the present study aimed to investigate the behavioral and regeneration responses of the freshwater planaria Girardia tigrina exposed to polyethylene (PE) microplastics (MPs) incorporated into their food source. The greatest effect was observed on planarian regeneration, which was manifested at 10 μg/mg liver. Planaria reproduction and fertility were affected at 50 μg/mg liver; however, planaria locomotion was not affected at the concentrations evaluated. Mid-infrared absorption spectroscopy (FT-IR) was used to identify the constituent polymers, and ingestion of the polyethylene microplastic by the planaria was confirmed by infrared spectroscopy. The results highlight the potential adverse effects of exposure to polyethylene microplastic and show that the reproductive behavior and regeneration of a freshwater organism can be indicators of toxicity resulting from environmental pollution.
摘要：
微塑料颗粒在全球淡水生态系统中大量出现，种类繁多，跨越湖泊和河流，越来越频繁地接触水生生物。关于塑料颗粒任何作用机理的研究仍然很少，特别是关于生物群的再生能力，没有建立的模式生物；然而，涡虫对评估这些对水生环境的风险表现出敏感性。因此，本研究旨在研究暴露于掺入其食物来源的聚乙烯（PE）微塑料（MPs）的淡水涡虫的行为和再生反应。观察到对涡虫再生的最大影响，表现为10μg/mg肝脏。在50μg/mg的肝脏中，planaria的繁殖和生育能力受到影响；但是，在评估的浓度下，涡虫的运动不受影响。采用中红外吸收光谱法(FT-IR)对聚合物的组成成分进行鉴别,并通过红外光谱证实了涡虫对聚乙烯微塑料的摄取。结果突出了暴露于聚乙烯微塑料的潜在不利影响，并表明淡水生物的生殖行为和再生可能是环境污染造成的毒性指标。
