Tan Mengyu, Sun Yue, Gui Jiaxi, Wang Jingli, Chen Xu, Song Wei, Wu Donglei
College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
China Urban Construction Design & Research Institute, Beijing 100120, China.
Sci Total Environ. 2022 Dec 15;852:158440. doi: 10.1016/j.scitotenv.2022.158440. Epub 2022 Aug 31.
Enormous production, use, and disposal of plastic goods present great challenges to environmental sustainability. Microplastics (MPs) are added into land which may serve as a larger MP repository than the ocean. Organic solid wastes and their biologically treated products can easily enter the soil and accumulate in soil systems. The current work deals with the extraction, identification, and distribution of MPs in typical organic solid wastes (food waste, livestock manure, and sludge) and their biologically treated products. The ecological risks of MPs were also preliminarily evaluated. The results showed that the abundance of MPs in organic solid wastes was in order of sludge > food waste > livestock manure. The main categories of MPs were fibers and films including PE, PP, and PET. The colors of MPs were mainly black, red, blue, and green. MPs generally exhibited bulges, depressions, cracks, or holes after biological treatment, and would be degraded into smaller fragments with potentially greater ecological risks. It was also found that the polymer risk index (H) of MPs in semi-dynamic composting products, compound fertilizer, and biogas residue of sedimentation tank sludge were higher than 10, reflecting their high ecological risk. Thus, it is recommended that the input of (micro)plastics to organic solid wastes streams should be minimized and related management should be established for the utilization of organic solid wastes and their biologically treated products.
塑料制品的大量生产、使用和处置给环境可持续性带来了巨大挑战。微塑料（MPs）被添加到土地中，土地可能成为比海洋更大的微塑料储存库。有机固体废物及其生物处理产品很容易进入土壤并在土壤系统中积累。当前的工作涉及典型有机固体废物（食物垃圾、畜禽粪便和污泥）及其生物处理产品中微塑料的提取、鉴定和分布。还初步评估了微塑料的生态风险。结果表明，有机固体废物中微塑料的丰度顺序为污泥>食物垃圾>畜禽粪便。微塑料的主要类别是纤维和薄膜，包括聚乙烯（PE）、聚丙烯（PP）和聚对苯二甲酸乙二酯（PET）。微塑料的颜色主要为黑色、红色、蓝色和绿色。经过生物处理后，微塑料通常会出现凸起、凹陷、裂缝或孔洞，并会降解为更小的碎片，可能具有更大的生态风险。研究还发现，沉淀池污泥的半动态堆肥产品、复合肥和沼渣中微塑料的聚合物风险指数（H）高于10，反映出其较高的生态风险。因此，建议尽量减少（微）塑料进入有机固体废物流，并应建立相关管理措施，以利用有机固体废物及其生物处理产品。
