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

在INTERNANO的第一阶段，IMPACT发现初始粒径、表面涂层、pH值和测试介质中DOC的存在会触发离子释放纳米颗粒（NP）的效果，如Ag NP。相比之下，pH值对于非离子释放纳米颗粒（如TiO2 NP）似乎没有太大影响。然而，这些纳米颗粒的晶体结构决定了它们的生态毒理学潜力，这在一定程度上可以通过反应表面积的偏差来解释。此外，TiO2 NP改变了其他环境应激源（如重金属）的生态毒性（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）。这表明纳米颗粒效应确实是由它们的初始成分驱动的，而环境参数可能至少部分地掩盖了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关联）以及触发（与紫外线照射、重金属和有机化学品结合）后引起的毒性机制。基于第一阶段的理解，IMPACT还将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。这两个方面都将导致对NP的环境问题及其潜在机制的更全面的了解。具体而言，我们提出以下研究问题：1。EINP的掩蔽、捕获、溶解和触发在多大程度上影响暴露的大型无脊椎动物的摄取、营养转移和行为？在洪泛平原地区的典型环境条件下，这些影响是否可逆？NPs的掩蔽、捕获、溶解和触发是否影响生态系统功能？这些假设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变化和生态相关终点的评估。IMPACT将受益于MASK，它制备的纳米颗粒具有不同的掩蔽，其强度也各不相同。此外，MASK将表征水中纳米颗粒（如DLS， NTA， hplc - uv - fdicp -MS和sp- hplc - icp -MS）和测试生物体（如ETV-ICP-MS， ESEM-EDX）， Raman （PORESURFACE）将用于定位生物体中的NP -主要是TiO2 NP -。此外，IMPACT将有助于INTERNANO联合洪泛平原实验和河岸过滤实验，并协调联合食物网和生态系统功能实验。

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.