Multi-scale Investigations of the Environmental Transformation, Fate and Inhibitory Effects of Engineered Nanoparticles

工程纳米粒子（ENPs），如碳纳米管，银纳米粒子（nAg），和金属氧化物，现在可以发现在超过1000个商业产品。尽管纳米技术有许多预期的好处，但人们非常担心我们还没有完全了解与这场革命相关的环境和健康风险。目前，在加拿大还没有针对ENP的具体法规，环境和公共卫生保护机构正在争先恐后地收集解决与纳米技术有关的安全和监管问题所需的数据。美国国家研究理事会最近提出了一项新的研究战略，环境，健康和安全（EH&S）方面的ENPs，建议研究应集中在关键要素，如物理，化学和生物转化，最终控制ENP的持久性，生物利用度，反应性和毒性。这些转变的复杂性和动态性使我们预测环境中ENP释放相关风险的能力变得复杂。基于我以前的NSERC发现资助的成果，拟议研究计划的5年目标是建立常见的物理，化学和生物转化对土壤和水生环境中选定ENPs的运输，命运和抑制作用的影响。拟议的工作首次系统地研究了不同的物理、化学和生物转化对ENP在相关的长期暴露时间内的归宿和影响的复杂影响。该研究将集中在两个ENPs中，发现在最大数量的商业产品（nAg）或生产的最大数量（nTiO 2）。该研究计划的长期目标是为全球努力确定和量化与ENPs相关的环境和公共卫生风险做出有影响力的贡献。我们的研究将提供知识基础和资源，以追求创新的研究在水体系中的胶体现象。显然，这项研究的潜在影响涵盖了广泛的工业、环境和生物医学应用。科学方法将包括使用最先进的实验技术对ENP聚集、溶解、运输和抑制/毒性进行受控实验室研究，包括单粒子电感耦合等离子体质谱法、纳米粒子跟踪分析、具有耗散监测的石英晶体微天平和具有增强暗场显微镜的高光谱成像。通过系统地改变关键的环境条件和ENP特性（例如，尺寸、表面涂层化学、核心化学），我们将开发可测量参数与EH&S风险评估目标终点之间的函数关系。为了使这些受控实验室实验与自然条件相联系，还将利用从加拿大地理位置收集的土壤和地下水进行研究。这项研究与ENPs具有精心控制，但可变的表面功能化，尺寸和核心特性将在支持全球环境风险评估工作作出重大的变革性贡献。这项研究的结果将是至关重要的加拿大ENP生产商的安全ENP的发展。拟议的研究计划优先考虑使用综合多学科方法和协作培训环境的HQP的培训。至少3个博士学位，3名工程硕士，5名本科生将被整合到一个拥有丰富经验的大型研究团队中。通过该计划培训的学生将在工程和应用科学的新兴领域的加拿大劳动力中具有重要价值。

Engineered nanoparticles (ENPs) such as carbon nanotubes, silver nanoparticles (nAg), and metal oxides can now be found in over 1000 commercial products. Despite the numerous anticipated benefits of nanotechnology, there is great concern that we do not yet fully understand the environmental and health risks associated with this revolution. Currently, there are no ENP-specific regulations in effect in Canada, and environmental and public health protection agencies are scrambling to gather the data required to address the safety and regulatory questions related to nanotechnology. The U.S. National Research Council recently proposed a new research strategy for environmental, health, and safety (EH&S) aspects of ENPs, recommending that research should focus on critical elements such as physical, chemical, and biological transformations that will ultimately control ENP persistence, bioavailability, reactivity, and toxicity. The complex and dynamic nature of these transformations complicates our ability to predict the risks associated with the release of ENPs in our environment. Building on the outcomes of my previous NSERC Discovery grant, the 5-year goal of the proposed research program is to establish the impacts of common physical, chemical, and biological transformations on the transport, fate and inhibitory effects of selected ENPs in soil and aquatic environments. The proposed work is the first to systematically examine the complex effects of different physical, chemical and biological transformations on ENP fate and impacts at relevant long-term exposure times. The research will focus on two of the ENPs that are found in largest number of commercial products (nAg) or produced in the largest quantities (nTiO2). The long-term objective of the research program is to make influential contributions to global efforts to identify and quantify the environmental and public health risks associated with ENPs. Our research will provide the knowledgebase and the resources to pursue innovative research on colloidal phenomena in aqueous systems. Clearly, the potential impact of the research spans over a broad range of industrial, environmental and biomedical applications. The scientific approach will include controlled laboratory studies of ENP aggregation, dissolution, transport and inhibition/toxicity using state-of-the-art experimental techniques, including single-particle-inductively coupled plasma mass spectrometry, nanoparticle tracking analysis, quartz crystal microbalance with dissipation monitoring, and hyperspectral imaging with enhanced darkfield microscopy. By systematically varying key environmental conditions and ENP properties (e.g., size, surface coating chemistry, core chemistry), we will develop functional relationships between measurable parameters and target end-points of EH&S risk assessment. To relate these controlled laboratory experiments to natural conditions, studies will also be conducted using soils and groundwater collected from Canadian geographical locations. This research with ENPs having carefully controlled but variable surface functionalization, sizes and core properties will make significant transformative contributions in supporting global environmental risk assessment efforts. The results of this research will be critical to Canadian ENP producers for the development of safe ENPs. The proposed research program prioritizes the training of HQP using an integrated multidisciplinary approach and a collaborative training environment. At least 3 Ph.D., 3 M.Eng., and 5 undergraduates will be integrated into a large research team where there is extensive existing experience. Students trained through this program will be of great value in the Canadian workforce in emerging areas of engineering and applied science.