Abstract：
Conventional plastics are inherently difficult to degrade, causing serious plastic pollution. With the development of society, biodegradable plastics (BPs) are considered as an alternative to traditional plastics. However, current research indicated that BPs do not undergo complete degradation in natural environments. Instead, they may convert into biodegradable microplastics (BMPs) at an accelerated rate, thereby posing a significant threat to environment. In this paper, the definition, application, distribution, degradation behaviors, bioaccumulation and biomagnification of BPs were reviewed. And the impacts of BMPs on soil and marine ecosystems, in terms of physicochemical property, nutrient cycling, microorganisms, plants and animals were comprehensively summarized. The effects of combined exposure of BMPs with other pollutants, and the mechanism of ecotoxicity induced by BMPs were also addressed. It was found that BMPs reduced pH, increased DOC content, and disrupted the nitrification of nitrogen cycle in soil ecosystem. The shoot dry weight, pod number and root growth of soil plants, and reproduction and body length of soil animals were inhibited by BMPs. Furthermore, the growth of marine plants, and locomotion, body length and survival of marine animals were suppressed by BMPs. Additionally, the ecotoxicity of combined exposure of BMPs with other pollutants has not been uniformly concluded. Exposure to BMPs induced several types of toxicity, including neurotoxicity, gastrointestinal toxicity, reproductive toxicity, immunotoxicity and genotoxicity. The future calls for heightened attention towards the regulation of the degradation of BPs in the environment, and pursuit of interventions aimed at mitigating their ecotoxicity and potential health risks to human.
摘要：
传统的塑料本身就很难降解,造成严重的塑料污染。随着社会的发展,生物降解塑料（BPs）被认为是传统塑料的替代品。然而,目前的研究表明，BP在自然环境中不会完全降解。相反，它们可以加速转化为可生物降解的微塑料(BMP)，从而对环境构成重大威胁。在本文中,定义,应用程序,分布，退化行为，综述了BP的生物累积和生物放大作用。BMPs对土壤和海洋生态系统的影响，就物理化学性质而言，营养循环,微生物,植物和动物进行了全面的总结。BMPs与其他污染物联合暴露的影响，并探讨了BMP诱导的生态毒性机制。发现BMP降低了pH，DOC含量增加，破坏了土壤生态系统中氮素循环的硝化。枝干重量，土壤植物的豆荚数量和根系生长，BMPs抑制了土壤动物的繁殖和体长。此外，海洋植物的生长，和运动，BMPs抑制了海洋动物的体长和存活。此外,BMP与其他污染物联合暴露的生态毒性尚未得到统一的结论。暴露于BMP引起几种类型的毒性，包括神经毒性,胃肠道毒性,生殖毒性，免疫毒性和遗传毒性。未来要求更加重视对环境中BPs退化的监管，并寻求旨在减轻其生态毒性和对人类潜在健康风险的干预措施。
