Saygin Hasan, Baysal Asli
Application and Research Center for Advanced Studies, Istanbul Aydin University, Sefakoy Kucukcekmece, Istanbul 34295, Türkiye.
Department of Chemistry, Faculty of Science and Letters, Istanbul Technical University, Istanbul 34469, Türkiye.
Int J Mol Sci. 2025 Jul 25;26(15):7178. doi: 10.3390/ijms26157178.
Micro/nanoplastics (MNP) and endotoxin, typical emerging contaminants, can be found in marine aqueous systems due to various natural and anthropogenic activities, and their co-occurrence may influence the biophysicochemical characteristics of seawater. Moreover, endotoxins may be transported by the micro/nanoplastics or increase the deformation of these substances, comprising other risks to the ecosystem. However, the impacts of the co-occurrence of micro/nanoplastics and endotoxins in seawater remain unknown. We studied the effects of endotoxin at three concentration levels in seawater and its combined impact with micro/nanoplastics at three doses on biophysicochemical processes in seawater through spectroscopic analysis, leaching indicators (turbidity and humidification index), oxidative potential, antioxidant activity, and biofilm production. The results showed that the UV-VIS spectra of seawater changed with their co-occurrence. The co-presence of MNPs and endotoxins increased the turbidity in seawater, indicating the leaching of micro/nanoplastic in the presence of endotoxins. A higher humification index in seawater showed the formation of dissolved organic substances in micro/nanoplastic and endotoxin seawater compared to the results for untreated seawater. Dithioerythritol assay revealed the differences in oxidative potentials of plain seawater and seawater in the co-presence of micro/nanoplastics and endotoxins. An important biochemical reaction in seawater was tested using biofilm formation. The results showed higher biofilm formation in their co-presence. This study provides new insights into the effects of micro/nanoplastics and their composite pollution with endotoxins on biophysiochemical indicators in seawater.
微塑料/纳米塑料（MNP）和内毒素是典型的新兴污染物，由于各种自然和人为活动，它们存在于海洋水系统中，并且它们的共存可能会影响海水的生物物理化学特性。此外，内毒素可能会通过微塑料/纳米塑料进行运输，或者增加这些物质的变形，从而对生态系统构成其他风险。然而，微塑料/纳米塑料与内毒素在海水中共存的影响仍然未知。我们通过光谱分析、浸出指标（浊度和湿度指数）、氧化电位、抗氧化活性和生物膜形成，研究了海水中三种浓度水平的内毒素及其与三种剂量的微塑料/纳米塑料共同作用对海水生物物理化学过程的影响。结果表明，海水的紫外可见光谱随着它们的共存而发生变化。微塑料/纳米塑料与内毒素的共存增加了海水的浊度，表明在内毒素存在的情况下微塑料/纳米塑料会发生浸出。与未处理海水的结果相比，海水中较高的腐殖化指数表明微塑料/纳米塑料与内毒素共存的海水中形成了溶解有机物。二硫苏糖醇试验揭示了纯海水以及微塑料/纳米塑料与内毒素共存的海水中氧化电位的差异。利用生物膜形成测试了海水中一个重要的生化反应。结果表明，它们共存时生物膜形成更多。本研究为微塑料/纳米塑料及其与内毒素的复合污染对海水中生物物理化学指标的影响提供了新的见解。
