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

汞在开阔海洋中的浓度很低(Fm-Pm)，并经历了复杂的生物地球化学循环。为了了解这种循环，有必要确定海洋中发现的主要汞物种(汞离子、元素汞、一甲基汞和二甲基汞；汞(II)、汞、毫米汞和二甲基汞)，这是必要的，但在分析上提出了艰巨的挑战。这些形式可能是挥发性的和光活性的，它们的低浓度使得即使是少量的污染也是毁灭性的。但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，在海洋中形成有机金属化合物(包括Ge、Se、Po、As的化合物)，评估人类活动元素的影响，以及可能开发古生产力替代指标。在该奖项的资助下，伍兹霍尔海洋研究所、康涅狄格大学、巴特尔纪念研究所和莱特州立大学的研究人员将参加即将举行的GEOTRACES校准巡航，以启动对海水中汞(Hg)形态测定的全面、多研究者/实验室比较。这种相互校准是在全面开展地球观测系统巡航活动之前的关键的第一步，以便在该项目范围内研究汞的化学海洋学的不同调查人员可以比较他们的结果，该项目的目的是分散进行，其范围不可能是一个实验室能够完成全部工作。该项目将由岸基和实地(参与两次巡航)两部分组成。在实验室中，该小组将测试由特氟龙以外的塑料制成的瓶子的清洁度，以及长期储存在邮轮期间收集的样品以进行总量和形态测量的前景。这项奖励将只支持该项目的实地部分，其余工作将由其他来源持续提供的支持来推动。这项工作以及随后的GEOTRACES研究的更广泛的影响包括更好地了解以鱼体内蓄积毫米汞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系统一样，这项国际校准工作将建立和维持国际合作的纽带。最后，参与这一努力的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，以帮助支持本科生、研究生和研究生的教育工作。

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.