MOLECULAR SCALE MERCURY SPECIATION IN FISH TISSUES FROM LAHONTAN RESERVOIR NY

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。在美国环境保护署即将开展的监测工作中，我们有兴趣研究汞形态通过低营养级别(例如浮游植物和浮游动物)的变化，这通常会产生更高的(有时是3到4个数量级)汞的生物累积系数，到高营养级别(例如大口鳕鱼)。在其他被汞污染的系统中，上层营养水平的猎鱼产生的汞浓度比美国环保局关于汞的水质指南(目前为0.3ppm)高出一个数量级。由于汞的毒性取决于其化学形态，因此在分子水平上了解汞的关联对于有效管理污染源和负荷以及为受采矿影响的水生系统开发综合水质模型至关重要。这一束流时间将被用来评估汞LIII边缘Bulk-XAS测量在研究地点不同生物中具有最高汞水平的大口黑鱼的可行性。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. In collaboration with upcoming monitoring efforts by the U.S. Environmental Protection Agency, we are interested in examining shifts in mercury speciation through lower-trophic levels (e.g., phytoplankton and zooplankton), which typically generate higher (sometimes by 3 to 4 orders of magnitude) bioaccumulation factors for mercury, to upper-trophic levels (e.g., large mouth bass). The upper trophic level game fish has been shown in other mercury-contaminated systems to generate mercury concentrations over an order of magnitude above the USEPA Water Quality Guideline for mercury (currently 0.3 ppm). Because the toxicity of mercury is dependent on its chemical speciation, understanding mercury associations on a molecular level is critical to the effective management of contaminant sources and loads as well as to the development of process-integrated water-quality models for mining-affected aquatic systems. This beam time will be used to assess the feasibility of Hg LIII-edge bulk-XAS measurements in large-mouth bass that has the highest levels of mercurty among different organisms at the study site.