Impact of Old and Recent Gold Mining Sites on Mercury Fluxes in Suspended Particulate Matter, Water and Sediment in French Guiana
Source abstract
Abstract
In 2006 the use of mercury (Hg) was banned for gold mining in French Guiana. However, mining of old placers could mobilize Hg accumulated in soils and sediment. This study aimed to measure the current impact of a mining concession (Boulanger site) on the Hg load in the watershed. Turbidity, Total Mercury (THg), and Monomethylmercury (MMHg) were measured in water, suspended particulate matter (SPM), river sediment and sediments from old tailing ponds along a river section of 30 km up and downstream from a mining concession in French Guiana during a dry and a rainy season. Total dissolved Hg (THgD) concentrations varied little from up- to down-stream but were all higher (fourfold on average) during the rainy season (3.2 to 4.4 ng L−1), than during the dry season and consistent with previous data known for the Amazonian area. Dissolved MMHg (MMHgD) represented up to 30% of THgD during the dry season, which is higher than previous results (typically around 2%). Mercury concentrations in sediments were highest in the vicinity of areas affected by old (before 2006) rather than new gold mining practices. Even though Hg was banned in 2006, present gold mining practices still release natural Hg and Hg inherited from older mining practices into the watershed.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Mercury impact and mitigation studies · Mining and Resource Management · Heavy Metal Exposure and Toxicity
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
BRGM, F-45060 Orléans, France
University of Bordeaux, UMR CNRS 5805 EPOC, Allée Geoffroy St. Hilaire, 33615 Pessac CEDEX, France
HYDRECO Guyane SARL, Laboratoire Environnement de Petit Saut, BP 823, 97 388 Kourou CEDEX, France
Funding
French Guiana Water Office · DEAL
References (39)
Show source-provided references
1. Socioeconomic Consequences of Mercury Use and Pollution10.1579/0044-7447(2007)36[45:SCOMUA]2.0.CO;2 ↗
2. Production aurifère et mercure utilisé de l’origine à nos jours
3. Mercury concentrations in inland waters of gold-mining areas in Rondônia, Brazil10.1016/0048-9697(89)90238-6 ↗
4. Carmouze, J.P., Lucotte, M., and Boudou, A. (2002). Le Mercure en Amazonie, Rôle de l’Homme et de l’Environnement, Risques Sanitaires, IRD Editions. EAN13: 9782709914673.10.4000/books.irdeditions.2519 ↗
5. Increase in mercury contamination recorded in lacustrine sediments following deforestation in the central Amazon10.1016/S0009-2541(99)00172-2 ↗
6. The effects of land use change on mercury distribution in soils of Alta Floresta, Southern Amazon10.1016/j.envpol.2003.10.013 ↗
7. Mercury loss from soils following conversion from forest to pasture in Rondonia, Western Amazon, Brazil10.1016/j.envpol.2005.02.026 ↗
8. Brearley, F.Q., and Thomas, A.D. (2015). Impact of gold mining on mercury contamination and soil degradation in Amazonian ecosystems of French Guiana. Land-Use Change Impacts on Soil Processes: Tropical and Savannah Ecosystems, CAB International.10.1079/9781780642109.0000 ↗
9. Sulfate-Reducing Bacteria: Principal Methylators of Mercury in Anoxic Estuarine Sediment10.1128/aem.50.2.498-502.1985 ↗
10. Mercury Methylation from Unexpected Sources: Molybdate-Inhibited Freshwater Sediments and an Iron-Reducing Bacterium10.1128/AEM.72.1.457-464.2006 ↗
11. Cet or qui file un mauvais mercure
12. Imprégnation de la population guyanaise par le mercure: Niveaux et sources d’exposition
13. Mason, R., and Pirrone, N. (2009). World emissions of mercury from artisanal and small scale gold mining. Mercury Fate and Transport in the Global Atmosphere: Emissions, Measurements and Models, Springer.10.1007/978-0-387-93958-2 ↗
14. Regional distribution of mercury in sediments of the main rivers of French Guiana (Amazonian basin)10.1186/2193-1801-3-322 ↗
15. Turbidity Suspended Sediment, and water clarity: A Review10.1111/j.1752-1688.2001.tb03624.x ↗
16. Amazonian former gold mined soils as a source of methylmercury: Evidence from a small scale watershed in French Guiana10.1016/j.watres.2011.02.022 ↗
17. An analytical protocol for the determination of total mercury concentrations in solid peat samples10.1016/S0048-9697(02)00035-9 ↗
18. Mercury speciation in the Lower St. Lawrence Estuary10.1139/f99-237 ↗
19. Potential and limits of speciated isotope-dilution analysis for metrology and assessing environmental reactivity10.1016/S0165-9936(04)00313-9 ↗
20. Mercury methylation in the sediments of a macrotidal estuary (Gironde Estuary, south-west France)10.1016/j.ecss.2010.07.007 ↗
21. Application of Isotopically Labeled Methylmercury for Isotope Dilution Analysis of Biological Samples Using Gas Chromatography/ICPMS10.1021/ac011157s ↗
22. Measurement of turbidity
23. Distribution and mobility of mercury in soils of a gold mining region, Cuyuni river basin, Venezuela10.1016/j.jenvman.2010.12.003 ↗
24. Distribution of chemical forms of mercury in sediments from abandoned ponds created during former gold mining operations in Colombia10.1016/j.chemosphere.2020.127319 ↗
25. Distribution of anthropogenic mercury in French Guyana river sediments downstream from gold mining sites
26. Quantifying the impacts of artisanal gold mining on a tropical river system using mercury isotopes10.1016/j.chemosphere.2018.12.036 ↗
27. Is mercury from small-scale gold mining prevalent in the southeastern Peruvian Amazon?10.1016/j.envpol.2016.08.038 ↗
28. River transport of mercury from artisanal and small-scale gold mining and risks for dietary mercury exposure in Madre de Dios, Peru
29. Total and methyl mercury distribution in water, sediment, plankton and fish along the Tapajós River basin in the Brazilian Amazon10.1016/j.chemosphere.2019.06.212 ↗
30. Impact of recent artisanal small-scale gold mining in Senegal: Mercury and methylmercury contamination of terrestrial and aquatic ecosystems10.1016/j.scitotenv.2019.03.108 ↗
31. The source and fate of sediment and mercury in the Tapajós River, Pará, Brazilian Amazon: Ground- and space-based evidence10.1016/j.jenvman.2005.09.027 ↗
32. Transport, distribution and speciation of mercury in the Amazon River at the confluence of black and white waters of the Negro and Solimões Rivers10.1002/hyp.1292 ↗
33. Distribution and partition of total mercury in waters of the Tapajós River Basin, Brazilian Amazon10.1016/S0048-9697(98)00093-X ↗
34. Impact of land degradation from mining activities on the sediment fluxes in two large rivers of French Guiana10.1002/ldr.3150 ↗
35. The geochemistery of mercury in central Amazonian soils developed on the Alter-do-Chao formation of the lower Tapajos River Vally, Para state, Brazil10.1016/S0048-9697(98)00265-4 ↗
36. Spatio-temporal geochemistry of mercury in waters of the Tapajós and Amazon rivers, Brazil10.4319/lo.2001.46.5.1141 ↗
37. Kirk, J.T.O. (1994). Light and Photosynthesis in Aquatic Ecosystems, Cambridge University Press.10.1017/CBO9780511623370 ↗
38. Determination of suspended particulate matter concentration from turbidity measurements: Particle size effects and calibration procedures10.1002/hyp.1220 ↗
39. Methylmercury formation in the anoxic waters of the Petit-Saut reservoir (French Guiana) and its spreading in the adjacent Sinnamary River