Source Partitioning of Metal Contaminants Using Stable Isotope Fractionation

我的研究计划的重点是开发工具，可用于环境污染的管理，如镉（Cd），锌（Zn）和汞（Hg）无机物质。受污染的环境，特别是高度污染的场所，往往是复杂的，往往是由多种排放源造成的。由于消除潜在有毒金属的所有来源是不现实的或不可能的，因此确定各种来源的相对贡献是必要的。这种方法被称为源分区，它是我的研究计划的核心。***我的目标是使用这些金属的稳定同位素比率来确定来自多个来源的金属对特定末端受体的相对贡献。理想情况下，末端受体是一个哨兵生物，整合了各种污染源和过程。***我们未来五年的主要测试地点将是珠江口（PRE），这是地球上污染最严重的地点之一。PRE的金属主要有三个来源：电子废物处理产生的废水、工业污水排放和主要由煤炭燃烧产生的物质在大气中的沉积。我们在PRE的初步工作包括在三角洲的十个站点测量牡蛎（Crassostrea hongkonggensis）中Cd、Zn、Cu和Ni同位素比值的变化。与此同时，我们将从三角洲最有可能的金属来源收集样本进行同位素分析。有了这些数据，我们就可以开始检查在这个复杂环境中进行源分区的可行性。***这项研究的直接影响将是通过对最重要的来源实施缓解措施，有可能减少地球上污染最严重的环境之一的金属污染。此外，这项工作的结果将为我们对金属污染源划分的理论框架提供重大改进。此外，这项工作将增加我们在各种环境介质中有效测量金属同位素比率的技术能力，这仍然是目前的一个挑战。最后，我的研究将使加拿大在这一新兴领域发挥主导作用，并在国际舞台上为减轻世界上一些污染最严重的地点作出贡献

The focus of my research program is the development of tools that can be used in the management of environments contaminated by inorganic substances such as cadmium (Cd), zinc (Zn), and mercury (Hg). Contaminated environments, particularly highly contaminated sites, tend to be complex, often resulting from multiple sources of emission. Because it isn't realistic or possible to eliminate all sources of potentially toxic metals, determining the relative contributions of various sources is necessary. This approach is called source partitioning and it is central to my research program.***My goal is to use the stable isotope ratios of these metals to determine the relative contributions of the metals from multiple sources to a specific end receptor. Ideally the end receptor is a sentinel organism that integrates the various contamination sources and processes.***Our primary test site for the next five years will be the Pearl River Estuary (PRE), which is one of the most contaminated sites on earth. There are three primary sources of metals to the PRE: effluents from e-waste processing, industrial sewage release and atmospheric deposition of materials primarily from coal combustion. Our initial work in the PRE consists of measuring variations in Cd, Zn, Cu and Ni isotope ratios in oysters (Crassostrea hongkongensis) from ten stations in the delta. At the same time we will collect samples for isotope analysis from the most likely sources of metals to the delta. With these data we can begin to examine the feasibility of source partitioning in this complex environment. ***The direct impact of this research will be the potential to reduce metal pollution to one of the earth's most contaminated environments by applying mitigation to the most important sources. In addition, the outcomes of this work will provide a significant improvement in our theoretical framework for metal contaminant source partitioning generally. Also this work will add to our technical ability to make valid measurements of metal isotope ratios in a variety of environmental media, which remains a challenge currently. Finally, my research will allow Canada to take a leading role in this emerging area and contribute on the international stage to mitigation of some of the most contaminated sites in the world.**