The extensive use of traditional non-biodegradable plastics results in the generation of microplastics (MPs), forming a new pollutant that can pose significant environmental risks. Biodegradable plastics (BP) possess degradation properties and can partially replace conventional plastics, thereby reducing pollution. However, further investigation is needed into the toxicity of biodegradable microplastics (BMPs) on aquatic organisms. This study explores the toxic effects of PBAT microplastics (PBAT-BMPs) and microplastics produced from degradable PBAT/TPS (thermoplastic starch) composite film (PBAT/TPS-BMPs) on zebrafish embryos. Our findings indicate that the presence of microplastics on the embryo's surface increases with higher BMPs concentration. Nonetheless, PBAT-BMPs tend to aggregate and are blocked by the embryonic membrane, thus diminishing their toxic effects on the embryo. Acute toxicity experiments revealed that 30 mg/L of PBAT-BMPs significantly reduced the survival rate of zebrafish embryos, whereas PBAT/TPS-BMPs had a lesser effect on survival. Both types of BMPs influenced the hatching rate of the embryos, leading to prolonged incubation periods. Additionally, both types of BMPs impacted the locomotor behavior of zebrafish larvae, causing an increase in larval locomotor speed. However, these BMPs had little impact on larval body development and heartbeat behavior. Fluorescent microplastic tracer experiments demonstrated that PBAT-BMPs persisted in juvenile fish for at least 144 h and were difficult to metabolize and excrete. Our study aims to gain a better understanding of the potential effects of BMPs on aquatic ecosystems and biological health, as well as to propose effective strategies for reducing environmental pollution and protecting organisms.

中文翻译：

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PBAT微塑料的制备及其对斑马鱼胚胎和幼鱼的潜在毒性


传统的不可生物降解塑料的广泛使用会产生微塑料（MP），形成一种新的污染物，可能造成严重的环境风险。可生物降解塑料（BP）具有降解性能，可以部分替代传统塑料，从而减少污染。然而，可生物降解微塑料（BMP）对水生生物的毒性还需要进一步研究。本研究探讨了PBAT微塑料（PBAT-BMPs）和可降解PBAT/TPS（热塑性淀粉）复合膜（PBAT/TPS-BMPs）生产的微塑料对斑马鱼胚胎的毒性作用。我们的研究结果表明，胚胎表面微塑料的存在随着 BMP 浓度的升高而增加。尽管如此，PBAT-BMP 往往会聚集并被胚胎膜阻断，从而减少它们对胚胎的毒性作用。急性毒性实验表明，30 mg/L的PBAT-BMPs显着降低斑马鱼胚胎的存活率，而PBAT/TPS-BMPs对存活率的影响较小。两种类型的 BMP 都会影响胚胎的孵化率，导致孵化期延长。此外，两种类型的 BMP 都会影响斑马鱼幼虫的运动行为，导致幼虫运动速度增加。然而，这些BMP对幼虫身体发育和心跳行为影响不大。荧光微塑料示踪实验表明，PBAT-BMPs在幼鱼体内持续存在至少144小时，并且难以代谢和排泄。我们的研究旨在更好地了解 BMP 对水生生态系统和生物健康的潜在影响，并提出减少环境污染和保护生物体的有效策略。