Laboratory of Microbial Biotechnologies, Agrosciences and Environment, (BioMAgE) Labeled Research Unit-CNRST N°4, Faculty of Sciences Semlalia, Cadi Ayyad University Marrakech, Morocco.
CNRS, Institute for Ecology and Environmental Sciences (IEES), UMR (Sorbonne U, CNRS, INRAE, IRD, UPEC), 75005, Paris, France.
J Environ Manage. 2022 Sep 1;317:115364. doi: 10.1016/j.jenvman.2022.115364. Epub 2022 May 23.
Microplastics (MP) are ubiquitous contaminants and their presence in sewage sludge has recently received attention as they may enter agro-ecosystems if sludge is used as organic soil amendment. Indeed, plastic particles (<5 mm) can be transported from wastewater and sewage sludge to the soil environment either directly within the plastic matrix or indirectly as adsorbed substances. In this paper, articles from 18 countries reporting the MP quantity and their characteristics in sewage sludge from wastewater treatment plants were reviewed and the MP concentration size and type were compared. The data show that MP abundance in sewage sludge ranged globally from 7.91 to 495 × 10 particles kg with highest abundance of fiber shape and MP size of less than 500 μm. In this review, we summarized and discussed the methods most frequently used for extraction and characterization of MP in sewage sludge including organic matter removal, MP extraction; physical and morphological MP characterization and its chemical characterization for polymer identification. We also described the major factors potentially controlling the fate of MP during disposal strategies with particular focus on composting. We show that physical and microbiological factors are important for MP degradation during composting and suggest two remediation practices: (i) inoculation of the initial sludge with microbial plastic decomposers to remove MP from contaminated sewage sludge, and (ii) development of high temperature composting processes.
微塑料（MP）是普遍存在的污染物，由于其可能会随着污泥作为有机土壤改良剂而进入农业生态系统，因此最近人们开始关注其在污水污泥中的存在。事实上，塑料颗粒（<5 毫米）可以通过废水和污水污泥直接在塑料基质中或作为吸附物质间接转移到土壤环境中。本文综述了来自 18 个国家的文章，这些文章报道了污水处理厂污泥中 MP 的数量及其特性，并比较了 MP 浓度的大小和类型。数据表明，全球污水污泥中 MP 的丰度范围为 7.91 到 495×10 颗粒 kg，纤维形状的丰度最高，MP 尺寸小于 500μm。在这篇综述中，我们总结和讨论了最常用于提取和表征污水污泥中 MP 的方法，包括去除有机物、MP 提取、MP 的物理和形态特征及其化学特征以识别聚合物。我们还描述了在处置策略中控制 MP 命运的主要因素，特别是堆肥。我们表明，在堆肥过程中物理和微生物因素对 MP 的降解很重要，并提出了两种修复实践：（i）用微生物塑料分解菌接种初始污泥，以从受污染的污水污泥中去除 MP，以及（ii）开发高温堆肥工艺。
