Reducing Properties of Anaerobic Sediments: Molecular Probe Studies of Biogeochemistry and Contaminant Fate

环境地球化学和生物地球化学项目的这个奖项 保罗·G博士Tratnyek、V. Renganathan和大卫R.布恩 俄勒冈州环境科学与工程系研究生 厌氧沉积物中污染物归宿研究所。 的 研究得到了化学和地球科学部门的支持 以及MPS多学科活动办公室。 一些污染物 在厌氧土壤中进行还原，但生物化学和地球化学 控制化学反应的因素还没有被很好地理解。 的 这项研究的目标是开发分子探针， 海岸、河口和淡水沉积物中的还原过程 环境. 初步工作将使用2-氯苯乙酮（2-CAP）， 监测减排过程。 这种化学物质被还原成 2-（氯甲基）苄醇，当其通过电子转移反应时，和 还原为苯乙酮。 通过测量 沉积物中这三种化合物的含量， 土壤的还原能力将是 测定 苯乙酮的形成意味着与 细胞外烟酰胺，氢化物的少数可能来源之一， 这样的系统。 结果将与微生物学研究相关， 建立各种土壤中生物地球化学还原过程的模型。 将研究其他分子探针，作为更全面地 表征了真实的环境材料的还原能力。 氯代烃、亚砜和醌类等污染物可能会 在土壤中通过添加电子的化学反应转化 从环境来源的污染物，有机和 无机的 关于这些反应如何发生的细节以及 它们在不同类型土壤中的发生率和程度并不 充分了解，以预测污染物在环境中的命运。 本文提出了一种检验环境相关性的一般方法， 将开发各种模型，其长期目标是提供一个 这是一个对监管决策有用的预测工具。

This award in the Environmental Geochemistry and Biogeochemistry Program is made to Drs. Paul G. Tratnyek, V. Renganathan, and David R. Boone of the Department of Environmental Science and Engineering, Oregon Graduate Institute, for studies of contaminant fate in anaerobic sediments. The research is supported by the Divisions of Chemistry and Earth Sciences and the MPS Office of Multidisciplinary Activities. Some contaminants undergo reduction in anaerobic soils, but the biochemical and geochemical factors controlling the chemical reaction are not well understood. The goal of this research is to develop molecular probes that can elucidate reduction processes in sediments from coastal, estuarine, and freshwater environments. Initial work will use 2-chloroacetophenone (2-CAP) to monitor the reduction process. This chemical is reduced to 2-(chloromethyl)benzyl alcohol when it reacts by electron transfer, and to acetophenone when reduced by hydride transfer. By measuring the amount of each of these three compounds present in the sediment, the rate of reduction and the capacity of the soil for reduction will be determined. The formation of acetophenone implies reaction with extracellular nicotinamide, one of the few possible sources of hydride in such systems. Results will be correlated with microbiological studies to develop a model of the biogeochemical reduction process in various soils. Additional molecular probes will be studied as means of more fully characterizing the reducing capacity of real environmental materials. Pollutants such as chlorohydrocarbons, sulfoxides, and quinones can be transformed in soils by chemical reactions in which electrons are added to the contaminant from environmental sources, both organic and inorganic. The details about how these reactions occur as well as the rates and extent to which they occur in various types of soils are not sufficiently understood to predict contaminant fate in the environment. In this research a general method to test the environmental relevance of various models will be developed with the long-term goal of providing a predictive tool useful to regulatory decision-making.