Wastewater treatment plants (WWTPs) are considered to be the main sources of microplastic contaminants in the aquatic environment, and an in-depth understanding of the behavior of microplastics among the critical treatment technologies in WWTPs is urgently needed. In this paper, the characteristics and removal of microplastics in 38 WWTPs in 11 countries worldwide were reviewed. The abundance of microplastics in the influent, effluent, and sludge was compared. Then, based on existing data, the removal efficiency of microplastics in critical treatment technologies were compared by quantitative analysis. Particularly, detailed mechanisms of critical treatment technologies including primary settling treatment with flocculation, bioreactor system, advanced oxidation and membrane filtration were discussed. Thereafter, the abundance load and ecological hazard of the microplastics discharged from WWTPs into the aquatic and soil environments were summarized. The abundance of microplastics in the influent ranged from 0.28 particles L⁻¹ to 3.14 × 10⁴ particles L⁻¹, while that in the effluent ranged from 0.01 particles L⁻¹ to 2.97 × 10² particles L⁻¹. The microplastic abundance in the sludge within the range of 4.40 × 10³–2.40 × 10⁵ particles kg⁻¹. In addition, there are still 5.00 × 10⁵–1.39 × 10¹⁰ microplastic particles discharged into the aquatic environment each day Moreover, among the critical treatment technologies, the quantitative analysis revealed that filter-based treatment technologies exhibited the best microplastics removal efficiency. Fibers and microplastics with large particle sizes (0.5–5 mm) were easily separated by primary settling. Polyethene and small-particle size microplastics (<0.5 mm) were easily trapped by bacteria in the activated sludge of bioreactor system. The negative impact of microplastics from wastewater treatment plant was worthy of attention. Moreover, unknown transformation products of microplastics and their corresponding toxicity need in-depth research.

废水处理厂（WWTP）被认为是水生环境中微塑料污染物的主要来源，因此迫切需要对WWTP的关键处理技术中的微塑料行为进行深入了解。本文综述了全球11个国家/地区38个污水处理厂的微塑料特征和去除情况。比较了进水，出水和污泥中微量塑料的含量。然后，根据现有数据，通过定量分析比较了关键处理技术中微塑料的去除效率。特别是，讨论了关键处理技术的详细机理，包括絮凝的初步沉降处理，生物反应器系统，高级氧化和膜过滤。之后，总结了污水处理厂向水生和土壤环境排放的微塑料的丰度负荷和生态危害。进水中微塑料的丰度范围为0.28个颗粒L^-1至3.14×10 ⁴粒子L ^-1，而废水中的L值为0.01粒子L ^-1至2.97×10 ²粒子L ^-1。污泥中的微塑性丰度在4.40×10 ³ –2.40×10 ⁵颗粒kg ^{-1的范围内}。此外，仍有5.00×10 ⁵ –1.39×10 ¹⁰每天向水环境中排放的塑料微粒此外，在关键处理技术中，定量分析表明，基于过滤器的处理技术表现出最佳的塑料去除效率。大粒径（0.5-5 mm）的纤维和微塑料很容易通过初步沉降分离。聚乙烯和小粒径的微塑料（<0.5毫米）很容易被细菌捕获在生物反应器系统的活性污泥中。废水处理厂的微塑料的负面影响值得关注。此外，未知的微塑料转化产物及其相应的毒性需要深入研究。