Abstract
Although mercury (Hg) mining in the Almadén district ceased in May 2002, the consequences of 2000 years of mining in the district has resulted in the dissemination of Hg into the surrounding environment where it poses an evident risk to biota and human health. This risk needs to be properly evaluated. The uptake of Hg has been found to be plant-specific. To establish the different manners in which plants absorb Hg, we carried out a survey of Hg levels in the soils and plants in the most representative habitats of this Mediterranean area and found that the Hg concentrations varied greatly and were dependent on the sample being tested (0.13–2,695 μg g−1 Hg). For example, the root samples had concentrations ranging from 0.06 (Oenanthe crocata, Rumex induratus) to 1095 (Polypogon monspeliensis) μg g−1 Hg, while in the leaf samples, the range was from 0.16 (Cyperus longus) to 1278 (Polypogon monspeliensis) μg g−1 Hg. There are four well-differentiated patterns of Hg uptake: (1) the rate of uptake is constant, independent of Hg concentration in the soil (e.g., Pistacia lentiscus, Quercus rotundifolia); (2) after an initial linear relationship between uptake and soil concentration, no further increase in Hgplant is observed (e.g., Asparagus acutifolius, Cistus ladanifer); (3) no increase in uptake is recorded until a threshold is surpassed, and thereafter a linear relationship between Hgplant and Hgsoil is established (e.g., Rumex bucephalophorus, Cistus crispus); (4) there is no relationship between Hgplant and Hgsoil (e.g., Oenanthe crocata and Cistus monspeliensis). Overall, the Hg concentrations found in plants from the Almadén district clearly reflect the importance of contamination processes throughout the study region.
Similar content being viewed by others
References
Alloway, B. J. (2004). Bioavailability of elements in soil. In: O. Selinus, B. Alloway, J. A. Centeno, R. B. Finkelman, R. Fuge, U. Lindh, & P. Smedley (Eds.), Essentials of Medical Geology (pp. 347–372). Amsterdam: Elsevier.
Berzas Nevado, J. J., García Bermejo, L. F., & Rodríguez Martín-Doimeadios, R. C. (2003). Distribution of mercury in the aquatic environment at Almadén, Spain. Environmental Pollution, 122, 261–271.
Boening D. W. (2000). Ecological effects, transport, and fate of mercury: a general review. Chemosphere, 40, 1335–10351.
Castroviejo, S, et al. (1986–2005) (eds) Flora Ibérica. Plantas vasculares de la peninsula Iberica e Islas Baleares, vol 1–8, 14, 21. Serv. Public. C.S.I.C., Madrid.
Chaney, R., Brown, S., Li, Y. M., Scott Angle, J., Holmer, F., & Green C. (1995). Potential use of metal hyperaccumulators. Mining Environmental Management, 3, 9–11.
Cobbet, Ch. (2003). Heavy metals and plants––model system and hyperaccumulators. New Phytologist, 159, 289–293.
Crowder, A. (1991). Acidification, metals and macrophytes. Environmental Pollution, 71, 171–203.
Fernandez-Martínez, R., Loredo, J., Ordoñez, A., & Rucandio, M. A. (2005). Physicochemical characterization and mercury speciation of particle-size soil fractions from an abandoned mining area in Mieres, Asturias (Spain). Environmental Pollution, 142, 217–226.
Gray, J. E., Hines, M. E., Higueras, P., Adatto, I., & Lasorsa, B. K. (2004) Mercury speciation and microbial transformations in mine wastes, stream sediments, and surface waters at the Almadén mining district, Spain. Environmental Science and Technology, 38, 4285–4292.
Gustin, M.S. (2003). Are mercury emissions from geologic sources significant? Science of the Total Environment, 304, 153–167.
Gustin, M. S., Lindberg, S. E., Austin, K., Coolbaugh, M., Vette, A., & Zhang, H. (2000) Assessing the contribution of natural sources to regional atmospheric mercury budgets. Science of the Total Environment, 259, 61–71.
Gustin, M. S., Biester, H., & Kim, C. S. (2002) Investigation of the light-enhanced emission of mercury from naturally enriched substrates. Atmospheric Environment, 36, 3241–3254.
Higueras, P., Oyarzun, R., Munhá, J., & Morata, D. (2000a) The Almadén mercury metallogenic cluster (Ciudad Real, Spain): alkaline magmatism leading to mineralization processes at an intraplate tectonic setting. Revista de la Sociedad Geológica de España, 13, 105–119.
Higueras, P., Oyarzun, R., Munhá, J., & Morata, D. (2000b). Palaeozoic magmatic-related hydrothermal activity in the Almadén syncline (Spain): a long-lasting Silurian to Devonian process? Transactions of the Institution of Mining and Metallurgy, 109, B199–B202.
Higueras, P., Oyarzun, R., Biester, H., Lillo, J., & Lorenzo, S. (2003) A first insight into mercury distribution and speciation in soils from the Almadén mining district. Journal of Geochemical Exploration, 80, 95–104.
Higueras, P., Oyarzun, R., Lillo, J., Sánchez-Hernández, J. C., Molina, J. A., Esbrí, J. M., & Lorenzo S. (2006). The Almadén district (Spain): anatomy of one of the world’s largest Hg-contaminated sites. Science of the Total Environment, 356, 112–124.
Hildebrand, SG, Huckabee, JW, Sanz Díaz, F, Janzen, SA, Solomon, JA, Kumar, KD. 1980. Distribution of mercury in the environment at Almadén, Spain. Oak Ridge, Tenn., Oak Ridge National Laboratory, ORNL/TM−7446.
Kovalevski, A. L. (1987). Biogeochemical exploration for mineral deposits Utrecht: VNU Science Press.
Lodenius, M., Tulisalo, E., & Soltanpour-Gargari, A. (2003). Exchange of mercury between atmosphere and vegetation under contaminated conditions. Science of the Total Environment, 304, 169–174.
Loredo, J., Ordóñez, A., Gallego, J. R., Baldo, C., & García-Iglesias, J. (1999). Geochemical characterization of mercury mining spoil heaps in the area of Mieres (Asturias, northern Spain). Journal of Geochemical Exploration, 67, 377–390.
Millán, R., Gamarra, R., Schmid, Th., Vera, R., Sierra, M. J., Quejido, A. J., Sánchez, D. M., & Fernández, M. (2004). Mercury content in natural vegetation of three plots in the mining area of Almadén (Spain). RMZ – Materials and Geoenvironment, 51, 155–158.
Patra, M., & Sharma, A. (2000). Mercury toxicity in plants. Botanical Review, 66, 379–422.
Pignatti, S. (1982). Flora d’Italia. Bologna: Edagricole (pp. 1–3).
Reeves, R. D., Baker, A. J. M., & Brooks, R. R. (1995). Abnormal accumulation of trace metals by plants. Mining Environmental Management, 3, 4–8.
Rivas-Martínez, S. (1987). Memoria del mapa de series de Vegetación de España. 1: 400.000. Madrid: Ministerio de Agricultura, Pesca y Alimentación, ICONA (p. 268).
Rivas-Martínez, S., Fernandez-González, F., Loidi, J., Lousã, M., & Penas, A. (2001) Syntaxonomical checklist of vascular plant communities of Spain and Portugal to Association level. Itinera Geobotanica, 14, 5–341.
Scholtz, M. T., Van Heyst, B. J., & Schroeder, W. H. (2003) Modelling of mercury emissions from background soils. Science of the Total Environment, 304, 185–207.
Schwesig, D., & Krebs, O. (2003) The role of ground vegetation in the uptake of mercury and methylmercury in a forest ecosystem. Plant Soil, 253, 445–455.
Senesi, G. S., Baldassare, G., Senesi, N., & Radina, B. (1999). Trace element inputs into soils by anthropogenic activities and implications for human health. Chemosphere, 39, 343–377.
Soil Survey Staff 1999 Soil Taxonomy: a basic system of soil classification for making and interpreting soil surveys; U. S. Dep. A. Agric. Handb. N.436.
Sholupov, S. E., & Ganeyev, A. A. (1995). Zeeman absorption spectrometry using high frequency modulated light polarization. Spectrochim Acta, 50B, 1227–1238.
Tardío, J., Pascual, H., & Morales, R. (2005). Wild food plants traditionally used in the province of Madrid, Central Spain. Economic Botany, 59(2), 122–136.
USEPA. (1997) Mercury Study Report to Congress: Volume III Fate and Transport of Mercury in the Environment. Washington: Office of Air Quality Planning & Standards and Office of Research and Development (p 376).
Valdés B., Talavera S., & Fernández-Galiano E. (Eds). (1987) Flora vascular deAndalucía Occidental. Barcelona: Ketres Edit.
Viladevall, M., Font, X., & Navarro, A. (1999) Geochemical mercury survey in the Azogue Valley (Betic Area, SE Spain). Journal of Geochemical Exploration, 66, 27–35.
Acknowledgements
The authors wish to express their gratitude to Prof. Michael Barbour (University of California at Davis) for reviewing the manuscript and providing constructive suggestions. Dr. José Manuel Murillo and an anonymous referee are thanked for helpful comments and suggestions. Valuable aid with sample collection was received from J.M. Ruiz, and from M.A. Verdonze with the chemical analyses. The research was funded by the European Union FEDER funds (Project 1FD97-0814), Ministerio de Ciencia y Tecnología (grants REN2002-02231 and PPQ2003-01902) and the University of Castilla–La Mancha.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Molina, J.A., Oyarzun, R., Esbrí, J.M. et al. Mercury accumulation in soils and plants in the Almadén mining district, Spain: one of the most contaminated sites on Earth. Environ Geochem Health 28, 487–498 (2006). https://doi.org/10.1007/s10653-006-9058-9
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10653-006-9058-9