MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; Tianjin Engineering Research Center of Environmental Diagnosis and Contamination Remediation, Tianjin 300350, China.
MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; Tianjin Engineering Research Center of Environmental Diagnosis and Contamination Remediation, Tianjin 300350, China.
J Hazard Mater. 2024 Dec 5;480:136420. doi: 10.1016/j.jhazmat.2024.136420. Epub 2024 Nov 5.
The emerging contaminant N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD) and its ozone conversion product N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine quinone (6PPD-Q) pose a threat to aquatic ecosystems. Aquatic animals and plants exhibit vigorous responses at very low ambient concentrations. However, studies of submerged macrophytes, key producers in aquatic ecosystems, are limited and the full extent of their toxic effects and feedback mechanisms is unknown. To investigate the phytotoxicity of 6PPD and 6PPD-Q, we modeled plant responses to abiotic stress using Ceratophyllum demersum L. (C. demersum) as a representative submerged plant. Our findings indicate that 6PPD and 6PPD-Q disrupt physiological and biochemical processes in C. demersum, encompassing growth inhibition, reduction in photosynthetic pigments, induction of oxidative damage, and metabolic alterations. Moreover, unfavorable modifications to biofilms induced were also discernible supported by confocal laser scanning microscopy (CLSM) images and microbial community profiling. More importantly, we found a robust correlation between differentially expressed metabolites (DEMs) and dominant genera, and 6PPD and 6PPD-Q significantly altered their correlation. Overall, our results imply that even though C. demersum is a resilient submerged macrophyte, the toxic effects of 6PPD and 6PPD-Q cannot be disregarded.
新兴污染物 N-(1,3-二甲基丁基)-N'-苯基-对苯二胺（6PPD）及其臭氧转化产物 N-(1,3-二甲基丁基)-N'-苯基-对苯二胺醌（6PPD-Q）对水生生态系统构成威胁。水生动物和植物在非常低的环境浓度下表现出强烈的反应。然而，对水生生态系统中的关键生产者——沉水植物的研究有限，其毒性作用和反馈机制的全貌尚不清楚。为了研究 6PPD 和 6PPD-Q 的植物毒性，我们使用金鱼藻（Ceratophyllum demersum L.）作为代表性的沉水植物，模拟了植物对非生物胁迫的反应。研究结果表明，6PPD 和 6PPD-Q 破坏了金鱼藻的生理和生化过程，包括生长抑制、光合色素减少、氧化损伤诱导和代谢改变。此外，共聚焦激光扫描显微镜（CLSM）图像和微生物群落分析也表明，生物膜也受到了不利的改变。更重要的是，我们发现差异表达代谢物（DEMs）和优势属之间存在很强的相关性，6PPD 和 6PPD-Q 显著改变了它们之间的相关性。总的来说，我们的研究结果表明，尽管金鱼藻是一种有弹性的沉水植物，但不能忽视 6PPD 和 6PPD-Q 的毒性作用。
