Stable isotope studies of the bioavailability of trace metals

我的研究计划由三部分组成：开发用于环境分析的新分析工具，开发关于环境中痕量金属去向和分布的预测模型和理论，以及开发减少工业活动对环境的排放的技术。 该提案侧重于前两项活动，特别强调与水生生物相互作用的痕量金属的命运和分布。痕量金属通常有不止一种同位素(质子数量相同，但总质量不同)，我们可以测量特定金属的每种同位素的量。每种同位素在自然界中的行为略有不同(这种现象被称为分馏)，我们可以测量这种差异。我的工作旨在利用同位素比率的微小差异来确定环境中金属污染的来源和命运。 目前，人们对同位素分馏的机制知之甚少，尤其是与水生生物群有关的分馏机制。我们的目标是了解控制水生生物群中同位素分馏的因素，以便我们能够将观察到的微小差异用作确定有机体从哪里获得污染的手段--这是一个称为来源分配的过程。这项研究将有助于我们了解痕量金属在环境中的行为，并有助于我们管理金属污染物的能力。

My research program consists of three components: development of new analytical tools for environmental analysis, development of predictive models and theories concerning the fate and distribution of trace metals in the environment and the development of technologies for the mitigation of releases to the environment by industrial activities. This proposal focuses on the first two of these activities with a particular emphasis on the fate and distribution of trace metals that interact with aquatic organisms. Trace metals often have more than one isotope (same number of protons but different total mass) and we can measure the amounts of each of the isotopes for a particular metal. Each isotope behaves slightly differently in nature (a phenomenon called fractionation) and we can measure the differences. My work aims to use the very small differences in isotope ratios to determine the sources and fate of metal contamination in the environment. At present very little is known about the mechanisms of isotope fractionation, particularly as they relate to aquatic biota. Our goal is to develop an understanding of the factors that control isotope fractionation in aquatic biota so that we can use the small differences observed as a means of determining from where an organism obtains contamination - this is a process called source partitioning. This research will contribute to our understanding of how trace metals behave in the environment and to our ability to manage metal pollutants.