College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China.
Institute of Quality Standard and Monitoring Technology for Agro-Products of Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China.
Sci Total Environ. 2023 Jul 1;880:163307. doi: 10.1016/j.scitotenv.2023.163307. Epub 2023 Apr 6.
Nanoplastics adsorb surrounding organic contaminants in the environment, which alters the physicochemical properties of contaminants and affects associated ecotoxicological effects on aquatic life. The current work aims to explore the individual and combined toxicological implications of polystyrene nanoplastics (80 nm) and 6:2 chlorinated polyfluorinated ether sulfonate (Cl-PFAES, trade name: F-53B) in an emerging freshwater fish model Hainan Medaka (Oryzias curvinotus). Therefore, O. curvinotus were exposed to 200 μg/L of PS-NPs or 500 μg/L of F-53B in the single or mixture exposure for 7 days to investigate the effects on fluorescence accumulation, tissue damage, antioxidant capacity and intestinal flora. The PS-NPs fluorescence intensity was significantly higher in the single exposure treatment than it in combined exposure treatment (p < 0.01). Histopathological results showed that exposure to PS-NPs or F-53B inflicted varying degree of damages to the gill, liver, and intestine, and these damage were also present in the corresponding tissues of the combined treatment group, illustrating a stronger extent of destruction of these tissues by the combined treatment. Compared to the control group, combined exposure group elevated the malondialdehyde (MDA) content, superoxide dismutase (SOD) and catalase (CAT) activities except in the gill. In addition, the adverse contribution of PS-NPs and F-53B on the enteric flora in the single and combined exposure groups was mainly characterised in the form of reductions in the number of probiotic bacteria (Firmicutes) and this reduction was aggravated by the combined exposure group. Collectively, our results indicated that the toxicological effects of PS-NPs and F-53B on pathology, antioxidant capacity and microbiomics of medaka may be modulated by the interaction of two contaminants with mutually interactive effects. And our work offers fresh information on the combined toxicity of PS-NPs and F-53B to aquatic creatures along with a molecular foundation for the environmental toxicological mechanism.
纳米塑料会吸附环境中的周围有机污染物，这会改变污染物的物理化学性质，并影响其对水生生物的相关生态毒理学效应。本研究旨在探讨聚苯乙烯纳米塑料（80nm）和 6:2 氯代全氟醚磺酸（Cl-PFAES，商品名：F-53B）在新兴淡水鱼类模型海南鱵（Oryzias curvinotus）中的单一和联合毒性。因此，O. curvinotus 暴露于 200μg/L 的 PS-NPs 或 500μg/L 的 F-53B 中，进行单一或混合暴露 7 天，以研究其对荧光积累、组织损伤、抗氧化能力和肠道菌群的影响。PS-NPs 的荧光强度在单一暴露处理中显著高于联合暴露处理（p<0.01）。组织病理学结果表明，PS-NPs 或 F-53B 暴露对鳃、肝和肠造成不同程度的损伤，联合处理组的相应组织也存在这些损伤，表明联合处理对这些组织的破坏程度更强。与对照组相比，联合暴露组的丙二醛（MDA）含量、超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性均升高，除了鳃组织。此外，PS-NPs 和 F-53B 对单一和联合暴露组肠道菌群的不利影响主要表现为益生菌（Firmicutes）数量减少，而联合暴露组的这种减少更为严重。综上所述，我们的结果表明，PS-NPs 和 F-53B 对鱼类病理、抗氧化能力和微生物组学的毒性影响可能是由两种污染物相互作用的相互作用调节的。并且我们的工作为 PS-NPs 和 F-53B 对水生生物的联合毒性提供了新的信息，并为环境毒理学机制提供了分子基础。
