污泥中典型金属纳米颗粒的赋存形态特征及其土壤施用对植物毒性研究

我国每年有数亿万计的金属纳米颗粒（MNPs）随着污泥被排放进入环境地球系统。作为我国污泥资源化的重要发展方向，污泥农业土壤施用可能导致MNPs在农田土壤及植物中的积累，引发生物毒性。目前关于污泥中原生MNPs的赋存形态特征及其在土壤生态系统中的行为缺乏深入认识，对其导致的生物风险及评价也鲜有研究。本项目拟开展污泥中原生MNPs的赋存形态特征及其植物的生物有效性和毒性研究，以期①探明我国典型城市污泥中原生MNPs的浓度水平、粒径分布、化学形态；②揭示污泥堆肥及土壤施用过程中污泥中原生MNPs与主要环境组分相互作用机制，阐明影响其赋存形态特征和环境地球行为的关键因素；③结合代谢组学从分子水平上解析污泥中原生MNPs对植物生长的影响及其毒性机制。研究结果将为评估我国污泥土壤施用的环境风险及完善我国污泥排放标准提供有力的技术支撑和参考。

Numerous metal and metal oxide nanoparticles (MNPs) were released to the environment and earth system via the pathway of sludge and biosolids discharge. While in China, the application to agricultural soils is the primary resource recovery management of biosolids. However, the broad use of biosolids in agriculture may lead to the accumulation of the sludge-originated MNPs in the farmland soils and crop plants, which would further induce eco-toxicity. Currently, little is known about the occurrence and existence characteristics of MNPs in the sewage sludge, and there is also a knowledge gap on their environmental behavior and bioavailability in soils after being amended with sludge. Studies on the environmental risks of sludge-originated MNPs in the terrestrial system are lacking. This project will systematically investigate the occurrence, existence characteristics, environmental behavior of MNPs in the sewage sludge as well as their bioavailability and toxicity to plants. The objectives of this proposal are ① to obtain the concentration, particle size distribution, and elemental composition of MNPs in urban sewage sludge; ② to reveal the underlying mechanisms of the interactions between sludge-originated MNPs and environmental components and media during the sludge compost and agricultural land application, and understand the key factors influencing the geochemical behaviors and fate of MNPs; ③ to resolve the impact of sludge-originated MNPs onto the growth of plants, and elucidate the underlying toxicity mechanisms with metabolomics platform. This study would help to better access the environmental risks of the sludge land application as well as provide guidance for the regulation of sludge disposal and management.