GSA Connects 2023 Meeting in Pittsburgh, Pennsylvania

Paper No. 65-4
Presentation Time: 2:25 PM

HYDROGEOCHEMICAL ASSESSMENT OF FLUORIDE TOXICITY, SOURCES, AND HEALTH HAZARDS IN THE BONGO DISTRICT OF THE UPPER EAST REGION, GHANA


SUNKARI, Emmanuel Daanoba, Department of Geological Engineering, University of Mines and Technology, Tarkwa, Western Region 00233, Ghana; Geology, University of Johannesburg, Auckland Park Campus, Johannesburg, Johannesburg 2006, South Africa, OKYERE, Moses Boakye, Department of Geology, University of Johannesburg, Johannesburg, 2006, South Africa, MOURI, Hassina, Geology, University of Johannesburg, Auckland Park Campus, Johannesburg, 2006, South Africa, ADAMS, Salaam Jansbaka, School of Natural and Environmental Sciences, University of Environment and Sustainable Development, Somanya, Eastern Region 00233, Ghana, ZANGO, Musah Saeed, Geological Engineering, University for Development Studies, Tamale, Northern Region 00233, Ghana, BHATTACHARYA, Prosun, KTH-International Groundwater Arsenic Research Group, Department of Sustainable Development, Environmental Science and Engineering, KTH Royal Institute of Technology, Teknikringen 10B, Stockholm, SE-100 44, Sweden; KTH-International Groundwater Arsenic Research Group, Department of Sustainable Development, Environmental Science and Engineering, KTH Royal Institute of Technology, Teknikringen 10B, Stockholm, SE-100 44, Sweden; Department of Sustainable Development, Environmental Science and Engineering, KTH Royal Institute of Technology, Teknikringen 10B, Stockholm, SE-100 44, SWEDEN and ALI, Shakir, Department of Geology, University of Delhi, Delhi, New Delhi 110007, India

Fluoride (F¯) contamination in groundwater is a major challenge in many developing countries like Ghana. It is commonly observed that the heterogeneous nature of the geology plays a pivotal role in governing the fluoride mobilization in groundwater. Therefore, this study employed a multi-approach involving hydrogeochemistry and multivariate statistical analysis to investigate the geochemical controls on high F¯ in the geologically heterogeneous Bongo District of Ghana. The study also assessed the probable human health risks associated with consuming F¯ contaminated groundwater. The study revealed that the dominant water type identified in the area was Na-HCO3-Cl with other mixed water types. The F¯ levels ranged from 0.43 to 3.61 mg/L (average: 1.89 mg/L). Five principal components with Eigenvalues above 1.0, which explain a total variance of 88.8% were obtained from factor analysis indicating that both geogenic and anthropogenic sources control the groundwater chemistry. However, F¯ mobilization in groundwater is largely because of weathering, ion exchange reactions, and dissolution of F¯ bearing minerals found in the aquifers. Further, geochemical modelling indicates that the groundwater is undersaturated with respect to calcite, dolomite, fluorite, gypsum, anhydrite, aragonite, halite, and quartz. The human health risk assessment showed that children had higher hazard quotient values (0.61 – 5.11), implying they are more prone to dental fluorosis than the other age groups.

Therefore, it is recommended that artificial recharge along with sustainable defluoridation techniques such as absorption, electrodialysis, and precipitation should be adopted to remediate the high fluoride menace. In addition, cost-effective and Ghanaian-friendly natural coagulants/absorbents like Moringa oleifera and bone char can be promoted for usage at the household level to reduce the fluoride levels in groundwater prior to domestic usage.