Environmental fate of data poor inorganic contaminants- Developing novel tools and a better fundamental understanding

每年都有数以千计的新产品和新材料被开发出来，具有新的性能和反应性。事实上，许多用于制造太阳能电池、高性能磁体、电子器件和催化剂的技术关键材料都含有镧系元素或高活性纳米材料。虽然这些新兴产品有许多用途，而且产量也在大幅扩大，但关于其潜在环境影响的数据却很少。对这些新材料进行生态风险评估的一个关键缺失因素是对其在复杂环境介质中的浓度、形态和归宿进行可靠的测定。 我们小组的总体研究目标是确定，更好地理解和量化控制环境系统中金属的命运和生物利用度的主要生物化学过程。Discovery赠款将用于发展严格评估纳米材料和稀土金属的生态风险所需的基础科学和分析能力。资金将支持我们的研究的最基本的方面，特别是推进研究的三个相关领域： (i)发展我们的分析能力，以测量复杂系统中低浓度的小纳米颗粒，并区分人为和自然NP; (ii)改进了我们对主要物理化学过程（溶解、附聚、异附聚等）的基本理解决定纳米材料在自然系统中的命运; (iii)增加我们对自然系统中金属的化学形态如何与其生物利用度相关的机械理解。 对于纳米颗粒，它们的胶体稳定性（相对于团聚）和溶解肯定会影响它们的生物利用度。分析的发展将追求为我们提供一个新的能力，以衡量最小的纳米粒子（1-20纳米）在真实的和模拟的自然系统的命运。我们将通过改变重要的环境参数对颗粒的命运进行机理研究。即将增加的飞行时间感应耦合质谱仪（ICP-TOFMS）将为我们提供区分工程纳米材料与天然胶体的能力，并使我们能够在接近自然的条件下更仔细地检查异附聚。最后，工作将被设计为回避的机制，稀土金属络合物的表观生物利用度，并确定是否大于预期的生物吸收导致增加的生物效应。如上所述，拟议的工作是非常跨学科和基本的性质，旨在通过仔细检查控制新兴无机污染物的命运和生物利用度的分子基础，增加我们对环境风险的全面了解。

Thousands of new products and materials, with novel properties and reactivity, are being developed each year. Indeed, many of the technology critical materials used to fabricate solar cells, high performance magnets, electronics and catalysts incorporate either the lanthanide series elements or highly reactive nanomaterials. Although these emerging products have numerous applications and a greatly expanding production, few data are available about their potential environmental impacts. One critical missing element of ecological risk assessments for these novel materials are robust determinations of their concentrations, speciation and fate in complex environmental media. The overall research objective of our group is to identify, better understand and quantify the main biophysicochemical processes that control the fate and bioavailability of metals in environmental systems. The Discovery grant will be used to develop the underpinning science and analytical capacity that is required to rigorously evaluate the ecological risk of nanomaterials and rare earth metals. Funding will support the most fundamental aspects of our research, by specifically advancing three related fields of study: (i) development of our analytical capacity to measure low concentrations of small nanoparticles in complex systems and to distinguish anthropogenic from natural NP; (ii) improvements to our fundamental understanding of the main physicochemical processes (dissolution, agglomeration, heteroagglomeration, etc.) that determine the fate of nanomaterials in natural systems; (iii) increasing our mechanistic understanding on how the chemical speciation of metals in natural systems is related to their bioavailability. For nanoparticles, their colloidal stability (with respect to agglomeration) and dissolution are certain to influence their bioavailability. Analytical developments will be pursued to provide us with a novel ability to measure the fate of the smallest nanoparticles (1-20 nm) in both real and simulated natural systems. We will perform mechanistic studies on particle fate by varying important environmental parameters. The imminent addition of a time of flight - inductively coupled mass spectrometer (ICP-TOFMS) will provide us with the capacity to distinguish engineered nanomaterials from natural colloids and allow us to more closely examine heteroagglomeration under near natural conditions. Finally, work will be designed to eludicate the mechanism underlying the apparent bioavailability of rare earth metal complexes and to determine whether or not the greater than expected biouptake leads to increased biological effects. As seen above, the proposed work is extremely interdisciplinary and fundamental in nature and is designed to increase our overall understanding of environmental risk by carefully examining the molecular basis controlling the fate and bioavailability of emerging inorganic contaminants.