Metals are released and accumulated in both living and environmental systems, and given the complex matrices unique to the two systems, there exist ion extraction and detection methods. This dissertation aims to combine analytical methods of both biological and environmental sciences to provide a means to assess the biological impact of environmental pollution.;Instrumentation commonly used for trace metal detection is too large or power consuming for practical field use. One trace level analytical method, cyclic voltammetry (CV), was adapted for field deployment. After using a 50% v/v nitric acid ion extraction method and optimizing CV instrumentation (e.g. mercury free high surface area graphite electrode cleaning and eliminating nitrogen purge) lead levels were determined in situ at three polluted urban locations in New Orleans, Louisiana. The results were compared to an established ion extraction method (ASTM D 3974) and analytical analyses (differential pulse polarography and dispersive X-ray diffraction). Despite higher ion and organic detection limits (two orders and four orders of magnitude, respectively) compared to other detection methods and spurious results at one test site, the field deployable analytical methods and instrumentation will provide environmental researchers with tools for the rapid analysis of environmental samples and identification of localized polluted areas with ion concentrations greater than 10 ppm.;The research measured lead extraction with simulated digestive acid exposure to polluted kaolin clay and Bayou Trepagnier sediment in vitro. The lead accumulation potential in catfish and crayfish based upon these experiments and published findings by other researchers, was estimated in catfish and crayfish to be 29.6 and 133 ppm, respectively.;Further development of the techniques and hardware in this work may provide researchers with tools that can identify environmental lead levels and predict lead ion bioaccumulation.
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机译：金属会在生活和环境系统中释放和积累，并且鉴于这两种系统特有的复杂基质，存在离子提取和检测方法。本文旨在结合生物学和环境科学的分析方法，为评估环境污染对生物的影响提供一种手段。；用于痕量金属检测的常用仪器太大或在实际现场使用中耗电。一种痕量分析方法，循环伏安法（CV），适用于现场部署。在使用50％v / v硝酸离子提取方法并优化CV仪器（例如无汞的高表面积石墨电极清洁和消除氮吹扫）后，在路易斯安那州新奥尔良的三个污染城市现场就地测定了铅含量。将结果与既定的离子提取方法（ASTM D 3974）和分析分析（差分脉冲极谱法和色散X射线衍射）进行比较。尽管与其他检测方法相比，离子和有机物的检测限更高（分别为两个数量级和四个数量级），并且在一个测试地点的结果是虚假的，但现场可部署的分析方法和仪器将为环境研究人员提供快速分析环境的工具样品和离子浓度大于10 ppm的局部污染区域的识别;该研究在模拟的消化酸暴露于污染的高岭土和Bayou Trepagnier沉积物的条件下测量了铅提取量。根据这些实验和其他研究人员发表的发现，cat鱼和小龙虾中的铅累积潜力分别估计为cat鱼和小龙虾中的铅的潜在浓度分别为29.6和133 ppm 。；这项技术和硬件的进一步发展可能为研究人员提供工具可以识别环境铅水平并预测铅离子的生物积累。
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