RAMR2D network scholarship holders
Affiliated CEAs :
CEA-2IE: CEA for training and research in water, energy and environmental sciences and technologies in West and Central Africa
CEA-MS: Centre Emergent Mines et Sociétés of the Institut supérieur des mines de la géologie de Boké in Guinea
Impact of gold mining on ecosystems and populations in Burkina Faso and Guinea
Summary of the scientific project
Over the past ten years or so, extractive activities have been developing intensively in West Africa, particularly in gold mining regions. Rising prices and economic difficulties are driving increasing numbers of people towards this lucrative activity, whose negative externalities on the environment and health are poorly assessed. Gold extraction processes and the chemical products used to recover it lead to diverse and complex contamination involving contaminants such as mercury (Hg), cyanide (CN) and arsenic (As).
This project aims to understand the impact of mining activities on the contamination of surface waters, trophic chains and gold camp populations in Burkina Faso and Guinea, where gold is the main export product. To carry out this research project, we will first establish a baseline of mercury, cyanide and arsenic contamination of waters and trophic chains in two mining districts. Secondly, the study will identify the sources of pollution, the mechanisms and pathways by which contaminants are transferred to the environment, as well as those responsible for human exposure.
This last point will enable us to characterize the levels of impregnation of workers and residents living near gold-mining sites, in order to assess the potential health impact. Finally, two major questions: what aquatic plant species (macrophytes) and biofilms are capable of sequestering these contaminants in aquatic ecosystems? Can remediation systems be developed on the basis of these observations?
Integration of the thesis project into the local, regional and international scientific community:
To offset the disruptions to the biogeochemical cycles of contaminants in the environment (air, water, soil, trophic chains), as well as the health risks generated by these activities, mitigation/rehabilitation and remediation alternatives need to be developed in order to project ourselves into more desirable and sustainable alternative models.
Burkina Faso and Guinea are not isolated cases in the African context, where many countries are affected by the new gold rush linked to the rise in gold prices. My work in this thesis will be pioneering in Burkina Faso and Guinea, where no database on environmental contamination and population exposure to metals and metalloids currently exists.
This work will make it possible to inform government bodies of the deleterious consequences on the environment and the levels of exposure to targeted contaminants induced by these activities, and to target the ecosystem's receptacle compartments, enabling us to propose the development of low-cost remediation systems such as filter gardens.