Do titanium dioxide nanoparticles and chlorinated organic compounds influence each other's uptake and toxicity in fish? A multi-angle and -level approach towards a better understanding of the interaction and hazard of emerging nanomaterials and traditiona

工程纳米材料代表了水生生态系统中一类新的污染物。它们与传统环境污染物（即化学物质）的共存和相互作用，会产生综合毒理学效应，增加各自对水生生物群的危害。在这方面特别值得关注的是，纳米尺寸的材料（1 - 100纳米）可以跨越生物屏障，这对于大尺寸的颗粒来说通常是无法逾越的，因此，考虑到它们的高比表面积和吸附能力，它们可以作为表面结合毒物的载体（特洛伊木马效应）。然而，到目前为止，人们对水生生物，特别是鱼类中这些过程的发生和后果知之甚少。作为最丰富的纳米材料之一，二氧化钛（TiO2）纳米颗粒（NPs）和氯化有机化合物（氯化有机化合物）之间的组合效应迄今为止甚至完全未知。二氧化钛（TiO2）纳米颗粒是最受关注的持久性有机环境污染物之一。因此，本项目的总体目标是评估TiO2 NPs和氯化有机化合物是否会影响虹鳟鱼（Oncorhynchus mykiss）对彼此的吸收和毒性。具体而言，该项目旨在回答以下研究问题：- TiO2 NPs能否作为表面吸附的氯化有机化合物的载体，并将其运输到鱼细胞的质膜上，从而提高其在细胞内的可用性和效果？-在细胞水平上，二氧化钛NPs和氯化有机化合物的混合物是否在共享毒性终点方面表现出增强的效果？- TiO2 NPs能否通过鱼鳃上皮促进氯化有机化合物的吸收？- TiO2 NPs和氯化有机化合物在鱼类组织和器官中的积累、分布和毒性是否相互影响？

Engineered nanomaterials represent a novel class of contaminants in aquatic ecosystems. Their co-existence and interaction with traditional environmental pollutants, that is chemicals, could increase their respective hazards to aquatic biota due to combined toxicological effects. Of particular concern in this regard is that the nano-sized materials (1 - 100 nm) could be able to cross biological barriers, which are typically insurmountable for larger-sized particles and thereby, taking into account their high specific surface area and adsorption ability, act as vector for surface-bound toxicants (Trojan horse-effect). However, to this day there is only little knowledge on the occurrence and consequence of these processes in aquatic organisms, particularly in fish. The combination effects between one of the most abundant nanomaterials and one of the most concerning group of persistent organic environmental pollutants, namely titanium dioxide (TiO2) nanoparticles (NPs) and chlorinated organic compounds, are so far even completely unknown. The overall objective of this project is therefore to assess if TiO2 NPs and chlorinated organic compounds can influence each other's uptake and toxicity in rainbow trout (Oncorhynchus mykiss). Specifically the project aims to answer the following research questions: - Can TiO2 NPs act as vector for surface-adsorbed chlorinated organic compounds and transport them across the plasma membrane of fish cells thereby increasing their intracellular availability and effect? - Do mixtures of TiO2 NPs and chlorinated organic compounds exhibit enhanced effects with regard to shared toxicity endpoints at the cellular level? - Can TiO2 NPs facilitate the uptake of chlorinated organic compounds through fish gill epithelia? - Do TiO2 NPs and chlorinated organic compounds influence each other's accumulation, distribution and toxicity in fish tissues and organs?