Collaborative Research: A GEOTRACES Intercalibration of Collection, Handling and Analysis Methods for Mercury Species in Seawater

汞以极低的浓度存在于公海（fM - pM），并受到复杂的生物地球化学循环的影响。为了了解这种循环，确定海洋中汞的主要种类（汞离子、单质汞、单甲基汞和二甲基汞；汞（II）、汞º、MMHg和DMHg）是必要的，但这带来了艰巨的分析挑战。这些形式具有挥发性和光活性，它们的低浓度甚至使少量污染具有破坏性。但是，研究海洋中的汞也有重要的好处，包括增加对有毒金属的来源和生物积累动力学的了解，海洋中有机金属化合物（包括Ge， Se, Po, As）的形成，评估人为调动元素的影响，以及可能发展的古生产力代理。利用这笔资金，伍兹霍尔海洋研究所、康涅狄格大学、巴特尔纪念研究所和赖特州立大学的研究人员将参加即将到来的GEOTRACES Intercalibration巡航，以便对海水中汞（Hg）种类的测定进行全面的、多研究者/实验室的比较。这样的相互校准是全面开展GEOTRACES巡航活动之前的关键第一步，以便在该项目背景下研究汞的化学海洋学的各种研究人员可以比较他们的结果。该项目旨在分散，其范围如此之大，以至于没有一个实验室可能能够完成全部工作。该项目将包括岸上和实地（参加两次巡航）两部分。在实验室里，研究小组将测试由聚四氟乙烯以外的塑料制成的瓶子的清洁度，以及在巡航期间收集的样本长期储存的前景，以进行总数和物种测量。这笔奖金将只支持项目的外地部分，其他来源的持续支持将促进其余工作。这项工作以及随后的GEOTRACES研究的更广泛影响，包括更深入地了解以MMHg在鱼类体内积累的形式对人类和生态系统健康构成的严重威胁。此外，与一般的GEOTRACES一样，这项互校正工作将建立和维持国际合作的纽带。最后，在这项工作中，四个私人投资机构参与并在许多情况下寻求额外的杠杆资金来帮助支持本科、研究生和研究生水平的教育工作。

Hg is present at very low concentrations in the open ocean (fM - pM) and is subject to a complex biogeochemical cycling. To understand this cycling, determination of the major species of Hg found in the ocean (mercuric ion, elemental Hg, monomethylHg and dimethylHg; Hg(II), Hgº, MMHg and DMHg, respectively), is necessary but poses daunting analytical challenges. These forms can be volatile and photoactive, and their low concentrations make even small amounts of contamination ruinous. But there are important benefits to studying Hg in the ocean, including increased understanding of the source and bioaccumulation dynamics of a toxic metal, the formation of organometallic compounds (including those of Ge, Se, Po, As) in the ocean, assessing the impact of an anthropogenically mobilized element, and the possible development of a paleoproductivity proxy. With funding from this award, researchers at the Woods Hole Oceanographic Institution, University of Connecticut, Battelle Memorial Institute, and Wright State University will participate in the upcoming GEOTRACES Intercalibration cruises in order to initiate a comprehensive, multi-investigator/laboratory comparison of the determination of mercury (Hg) species in seawater. Such an Intercalibration is a critical first step prior to full fledged GEOTRACES cruise activities, so that the various investigators studying the chemical oceanography of Hg in the context of that project, which is intended to be decentralized and of such scope that no one lab would likely be capable of completing the whole effort, may compare their results. The project will consist of both a shore based and field (participation in the two cruises) components. In the laboratory, the team will test the cleanliness of bottles made from plastics other than Teflon, and the prospects of long-term storage of samples collected during the cruises for total and speciation measurements. This award will support only the field component of the project, with the remaining effort facilitated by on-going support from other sources. The broader impacts of this work, and that of the subsequent GEOTRACES studies, include a greater understanding of a serious human and ecosystem health threat in the form of MMHg accumulation in fish. In addition, and as with GEOTRACES in general, this Intercalibration exercise will forge and maintain bonds of international collaboration. Finally, the four PIs in this effort are engaged in, and in many cases seeking additional leveraging funds to help support, educational efforts at the undergraduate, graduate and post-graduate level.