Engineered inorganic nanoparticles transformed by environmental processes: Biological effects on aquatic invertebrates

在INTERNANO的第一阶段，Impact发现初始颗粒尺寸、表面涂层、pH和测试介质中DOC的存在会触发离子释放纳米颗粒(NP)的效果，如Ag NP。相反，对于不释放离子的纳米颗粒，如二氧化钛纳米颗粒，pH似乎是微不足道的。然而，这种纳米颗粒的晶体结构决定了它们的生态毒性潜力，这在一定程度上可以用反应表面积的偏差来解释。此外，二氧化钛纳米颗粒改变了其他环境应激源的生态毒性，如重金属(触发)。最后，纳米粒子效应的大小可以由环境因素控制，即DOC(掩蔽)和UV照射(触发)。这表明纳米颗粒的效应确实是由它们的初始组成驱动的，而环境参数至少可以部分地覆盖它们之间的逐渐差异。IMPACT将根据先前的结果，评估纳米颗粒在掩蔽(不同的NP涂层)和捕获(NP与不同粗糙度的有机材料等表面的结合)以及触发(与紫外线照射、重金属和有机化学品相结合)所造成的毒性机制。基于第一阶段的理解，IMPACT也会增加实验系统的生态复杂性。因此，重点还将包括NP对生态系统功能、异养食物链的吸收和营养转移的影响。这两个方面都将使人们更全面地了解核电厂的环境问题及其根本机制。具体来说，我们建议以下研究问题：1.掩蔽、捕捉、溶解和触发EINP在多大程度上影响暴露在水中的大型无脊椎动物的吸收、营养转移和行为？2.这些影响在泛滥平原地区的典型环境条件下是可逆的吗？3.掩蔽、捕捉、溶解和触发NPs是否影响生态系统功能？这些假说将通过有针对性的实验室研究进行评估，允许明确定义的环境改变和评估生态相关的端点。Impact将受益于MASK，它制备了具有不同掩膜的纳米颗粒，它们的强度也不同。此外，MASK将表征水中的纳米颗粒(例如DLS、NTA、HDC-UV-FDICP-MS和SP-HDC-ICP-MS)，而被测试生物(例如ETV-ICP-MS、ESEM-EDX)拉曼(PORESURFACE)将用于定位NP-主要是TiO2NP-在生物中的位置。此外，IMPACT还将为INTERNANO联合滩地实验和岸滩渗滤实验做出贡献，并协调食物网与生态系统功能联合实验。

During the first phase of INTERNANO, IMPACT uncovered that the initial particle size, surface coating, pH and the presence of DOC in the test medium trigger the effects of ion-releasing nanoparticles (NP) such as Ag NP. In contrast, pH seems to be of marginal importance for non-ion releasing nanoparticles, such as TiO2 NP. However, the crystalline structure of such nanoparticles determines their ecotoxicological potential, which is to some extent explainable by deviations in reactive surface area. Moreover, TiO2 NP alters the ecotoxicity of other environmental stressors, such as heavy metals (triggering). Finally, the magnitude of nanoparticle effects can be controlled by environmental factors, i.e. DOC (masking) and UV-irradiation (triggering). This indicates that nanoparticle effects are indeed driven by their initial composition, while environmental parameters may at least partly override the gradual difference among them.IMPACT will assess, based on the previous results, mechanisms of toxicity caused by nanoparticles following masking (different coating of NP) and catching (association of NP to surfaces such as organic materials with differing roughness) as well as due to triggering (in combination with UV-irradiation, heavy metals and organic chemicals). Based on the understanding during the first phase, IMPACT will also increase the ecological complexity of the experimental systems. Therefore, the focus will also include NP-related implications on ecosystem functions, uptake and trophic transfer along heterotrophic food chains. Both aspects will lead to a more comprehensive picture of the environmental concerns of NP and their underlying mechanisms. In detail, we suggest the following research questions:1. To which extent do masking, catching, dissolution as well as triggering of EINP affect the uptake, trophic transfer and the behavior of exposed macroinvertebrates?2. Are those effects reversible under environmental conditions typical for flood plain areas?3. Are masking, catching, dissolution and triggering of NPs affecting ecosystem functions?These hypotheses will be assessed by targeted laboratory studies allowing for well-defined environmental modifications and the assessment of ecologically relevant endpoints. IMPACT will benefit from MASK, which prepares nanoparticles with different masking, that also vary in their strength. Moreover MASK will characterize nanoparticles in water (e.g. DLS, NTA, HDC-UV-FDICP- MS and sp-HDC-ICP-MS) and test organisms (e.g. ETV-ICP-MS, ESEM-EDX) Raman (PORESURFACE) will be used to localize NP - mainly TiO2 NP - in the organisms. Moreover, IMPACT will contribute to the INTERNANO JOINT FLOODPLAIN EXPERIMENT and the BANK FILTRATION EXPERIMENT as well as coordinate the JOINT FOOD WEB & ECOSYSTEM FUNCTION EXPERIMENT.