Guangdong Provincial Key Laboratory of Water and Air Pollution Control, South China Institute of Environmental Sciences, MEE, Guangzhou, 510655, China; Department of Chemistry and Biochemistry, University of Mississippi, University, MS, 38677, USA.
Guangdong Provincial Key Laboratory of Water and Air Pollution Control, South China Institute of Environmental Sciences, MEE, Guangzhou, 510655, China.
J Environ Manage. 2023 Jan 1;325(Pt A):116411. doi: 10.1016/j.jenvman.2022.116411. Epub 2022 Oct 20.
Wastewater treatment plants (WWTPs) discharge metric tons of microplastics (MPs) daily to aquatic and terrestrial environments worldwide. Herein we provide a holistic review on MPs in the WWTPs, highlighting recent advances in sampling and analysis, improved understanding of their sources, occurrence, and degradation in treatment steps, and the potential risks MPs pose after being discharged in treated effluent and sludge. We discuss the merits and limitations of the various sampling and analytical approaches to determine MPs in major WWTP compartments; highlight new research on MP profiles (abundance, physical characteristics, and compositions) in raw sewage, treated effluent, and waste sludge, which are of particular interest when assessing MP sources, removal rates, and fate; and emphasize mechanisms of MP fragmentation and degradation within WWTPs as well as the potential sorption of wastewater contaminants to the MPs. We find that robust and standardized methods for determining MPs in WWTP samples is still urgently needed, and that complete removal of MPs from wastewater by WWTPs is not guaranteed, although the vast majority of MPs end up in sludge. Areas of research that deserve further attention include the fate of small (<20 μm) MPs, abiotic and biotic fragmentation of MPs in the WWTPs, and more empirical data with concentrations on a mass basis.
污水处理厂（WWTPs）每天向全球水和陆地环境排放数以吨计的微塑料（MPs）。本文对 WWTPs 中的 MPs 进行了全面综述，重点介绍了采样和分析方面的最新进展，加深了对其在处理过程中的来源、存在和降解的理解，以及在经过处理的污水和污泥排放后 MPs 可能带来的潜在风险。我们讨论了确定 WWTP 各个隔室中 MPs 的各种采样和分析方法的优缺点；强调了关于原始污水、处理后的污水和废物污泥中 MPs 特征（丰度、物理特性和组成）的新研究，这在评估 MPs 来源、去除率和归宿时尤为重要；并强调了 WWTP 内 MPs 碎裂和降解的机制以及废水污染物对 MPs 的潜在吸附作用。我们发现，仍然迫切需要用于确定 WWTP 样品中 MPs 的稳健和标准化方法，而且 WWTP 并不能保证将 MPs 从废水中完全去除，尽管绝大多数 MPs 最终都会进入污泥。值得进一步关注的研究领域包括小尺寸（<20μm） MPs 的归宿、WWTP 中 MPs 的非生物和生物碎裂以及基于质量浓度的更多经验数据。
