School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China; Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Nanjing 210044, China.
School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China; Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Nanjing 210044, China.
J Hazard Mater. 2024 Dec 5;480:136214. doi: 10.1016/j.jhazmat.2024.136214. Epub 2024 Oct 18.
The study assessed the acute toxicities of tire wear particles (TWPs) on activated sludge, comparing cryogenically ground TWPs (C-TWPs) with photo-aged (PA-TWPs), ozone-aged (OA-TWPs), and Fenton-aged (FA-TWPs) variants over 96 h. At 0.1 mg/L, TWPs showed no significant effects on sludge respiration or purification. However, at 50 mg/L, significant impacts on respiration, decontamination capacity, and microbial community structure were observed, particularly in aged TWPs. Specifically, aged TWPs, especially FA-TWPs, are prone to inducing necrosis by generating non-cellular reactive oxygen species (ROS) catalyzed by persistent free radicals, leading to an increase in lactate dehydrogenase release ranging from 215 % to 284 %. Conversely, C-TWPs tend to trigger apoptosis via intracellular ROS accumulation, leading to a 358 % increase in intracellular ROS. Aged TWPs exhibited higher affinities for proteins and polysaccharides, while C-TWPs preferred phospholipids. All TWPs adversely affected sludge dewatering, with strong correlations found between specific resistance to filtration (SRF) and total protein (r = 0.981, p < 0.001) and between bound water and early cell apoptosis (r = 0.961, p < 0.01). Additionally, a correlation between SRF and cellular necrosis (r = 0.956, p < 0.01) was noted, linked to increased protein and extracellular polymeric substance levels. These results emphasize substantial influence of aged TWPs on sludge dewatering efficiency via diverse bacterial cell death mechanisms.
本研究评估了轮胎磨损颗粒（Tire Wear Particles，TWPs）对活性污泥的急性毒性，比较了经冷冻研磨（Cryogenically Ground，C-TWPs）、光老化（Photo-aged，PA-TWPs）、臭氧老化（Ozone-aged，OA-TWPs）和芬顿老化（Fenton-aged，FA-TWPs）的 TWPs 在 96 小时内的毒性。在 0.1mg/L 时，TWPs 对污泥呼吸或净化没有显著影响。然而，在 50mg/L 时，呼吸、净化能力和微生物群落结构都受到了显著影响，尤其是在老化的 TWPs 中。具体来说，老化的 TWPs，特别是 FA-TWPs，容易通过持久自由基催化的非细胞活性氧物质（reactive oxygen species，ROS）诱导坏死，导致乳酸脱氢酶释放增加 215%至 284%。相反，C-TWPs 则通过细胞内 ROS 积累引发细胞凋亡，导致细胞内 ROS 增加 358%。老化的 TWPs 对蛋白质和多糖具有更高的亲和力，而 C-TWPs 则偏好磷脂。所有 TWPs 都对污泥脱水产生不利影响，比阻（specific resistance to filtration，SRF）与总蛋白之间存在很强的相关性（r=0.981，p<0.001），结合水与早期细胞凋亡之间存在很强的相关性（r=0.961，p<0.01）。此外，还观察到 SRF 与细胞坏死之间存在相关性（r=0.956，p<0.01），这与蛋白质和细胞外聚合物水平的增加有关。这些结果强调了老化 TWPs 通过不同的细菌细胞死亡机制对污泥脱水效率产生了重大影响。
