US-Ghana Dissertation Enhancement: A Geochemical Model and Geomedical Implications of Elevated Groundwater Fluoride Levels in the Upper East Region of Ghana

研究生Braimah Apambire先生在内华达大学和社区学院水资源中心的研究教授兼执行主任John Hess博士的指导下，在加纳进行实地研究。在加纳上东地区的家庭供水中发现了高水平的氟化物，目前儿童正在发生氟牙症(牙齿斑驳)。但人们对该地区氟化物的来源或浓度知之甚少。该项目将把来自UER的水文地质信息与地球化学模拟相结合，以确定地下水氟的来源和分布模式。Apambire先生假设：1)含水层中氟的来源是区域下伏岩石中含有弗洛林的矿物；2)含水层中氟的分布主要受区域地质、矿物氟的溶解度和各种氟化物复合体浓度的影响；3)氟斑牙的分布主要是地下水中氟浓度升高的结果。利用多元统计技术，Apambire先生将分析UER的岩石和水样，以确定含水层中的矿物来源和氟化物分布的地球化学控制。来自UER农村社区的儿童和年轻人的牙科信息将由Bolgatanga医院的一名高级牙科外科医生在Apambire先生和其他人的协助下收集。还将对这些信息进行分析，以确定不同年龄和性别群体的牙齿状况与地下水中氟浓度水平之间的相关性。加纳大学地质系和Bolgatanga医院牙科部门的工作人员将在这一项目上与Apambire先生合作，这项研究的结果将增加对氟的地球化学来源和地下水氟的分布模式的了解。这些新信息将成为政策制定者、水资源管理者和牙科健康教育工作者的宝贵资源。此外，该助学金将提供支持，使一个有前途的学生能够建立一个强大的，独立的研究事业。微软和地球科学部共同为这个项目提供资金。

This dissertation enhancement grant supports a graduate student, Mr. Braimah Apambire, working under the guidance of Dr. John Hess, Research Professor and Executive Director at the Water Resources Center with the University and Community College System of Nevada, to do field research in Ghana. High levels of fluoride have been identified in the domestic water supplies in the Upper East Region (UER) of Ghana, and dental fluorosis (tooth mottling) is now occurring in children. But little is known about the origin or concentrations of the fluoride in this region. This project will combine hydrogeologic information from the UER with geochemical modeling to determine the source and distribution pattern of groundwater fluoride. Mr. Apambire hypothesizes that: 1) sources of fluoride in the aquifers are florine-bearing minerals contained in the rocks underlying the area; 2) distribution of the fluoride in the aquifers is primarily influenced by the area's geology, the solubility of the mineral fluoride, and concentrations of various fluoride complexes; and 3) distribution of dental fluorosis is primarily a result of elevated concentrations of fluoride in the groundwaters. Using multivariate statistical techniques, Mr. Apambire will analyze rock and water samples from the UER to determine the mineral sources in the aquifers and the geochemical controls on fluoride distribution. Dental information on children and young adults from rural communities in the UER will be collected by a senior dental surgeon from the Bolgatanga Hospital, with assistance from Mr. Apambire and others. This information will also be analyzed to identify correlations between the dental status of the different age and gender groups and the fluoride concentration levels in the groundwater. Staff members in the Department of Geology at the University of Ghana and the dental unit at Bolgatanga Hospital will collaborate with Mr. Apambire on this project.The results of this study will increase the knowledge about the geochemical origin of fluoride and the distribution patterns of groundwater fluoride. The new information will be a valuable resource for policy makers, water resource managers, and dental health educators. Additionally the grant will provide support to enable a promising student to establish a strong, independent research career.ms and the Division of Earth Sciences are jointly providing funding for this project.