Heavy Metals in Soils of the Fatala River Basin (Republic of Guinea)

Abstract

Objectives: The objectives of this research include assessing the concentrations of heavy metals and trace elements in the Fatala River basin (Republic of Guinea), identifying the primary sources of these pollutants, analyzing their migration patterns, evaluating the ecological and health impacts, and contributing to the development of effective pollution mitigation strategies. The theoretical framework is grounded in understanding the anthropogenic impact on soil, the role of soil as a natural filter, the associated health risks, and the application of Geographic Information Systems (GIS) for detailed pollution analysis.   Theoretical Framework: Pollution from heavy metals and trace elements presents a significant threat to environmental health, a situation that has been exacerbated with the expansion of mining and industrial activities. Despite advancements in technology aimed at reducing soil contamination, many regions, particularly in developing countries, continue to experience unchecked pollution due to the lack of environmental safeguards. This study focuses on the Fatala River basin in the Republic of Guinea, a region heavily impacted by extensive mining activities and the growth of the population and settlements, which have led to the accumulation of heavy metals and trace elements in the soil.   Methods: In the analysis of soil samples collected from the river basin, the determination of heavy metal and trace element content was performed using an inductively coupled plasma mass spectrometer, specifically the PlasmaQuant MS Elite S-NR:11-6000ST043 instrument. The spatial distribution of these elements within the river basin was mapped using ArcGIS 10.8 software.To create a comprehensive representation of the distribution, mathematical interpolation of the values was carried out using the Interpolation tool (Spatial Analyst Tools) within ArcGIS 10.8. The inverse distance weighted (IDW) technique was employed for this purpose. To assess the extent and severity of soil contamination by heavy metals and trace elements in the study area, three key parameters were calculated: the hazard coefficient Ko, the concentration coefficient (Kc), and the total pollution index. These values provide a quantitative measure of the contamination levels and associated risks in the region.   Results and discussion: The analysis indicates that the concentrations of certain elements, such as silver (Ag), arsenic (As), beryllium (Be), cadmium (Cd), and selenium (Se), significantly exceed regulatory limits, posing a serious threat to the health of the population and the ecosystem of the river basin as a whole. The research categorized elements into four groups based on their hazard levels, ranging from those within acceptable concentration limits to those significantly exceeding them. Cadmium (Cd) is highlighted for its concentrations, which in some instances are 14 times above the standard limits. It also emphasizes the importance of further studies to identify the origins and assess the effects of selenium (Se), silver (Ag), and cadmium (Cd) on the river basin's ecosystem. The conclusion emphasizes the importance of developing strategies to reduce the harmful effects of pollutants, including the implementation of a system for regulating concentrations and measures for land reclamation.   Implications of the research: a map of the total pollution index of the Fatala river basin was constructed. It was revealed that most of the territory belongs to the moderately dangerous pollution category, which is characterized by an increase in the overall morbidity rate.   Originality/value: The authors stress the importance of conducting additional research, implementing a system for normalizing pollutant concentrations, and developing measures to reduce the detrimental impact of pollution on the environment and public health. This study serves as a valuable contribution to understanding the environmental implications of heavy metal and trace element pollution in the Fatala River basin and highlights the need for ongoing efforts to address this issue.