Natural Radionuclides, Rare Earths and Heavy Metals Transferred to the Wild Vegetation Covering a Phosphogypsum Stockpile at Barreiro, Portugal
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In Portugal, the industrial production of phosphate fertilizers, has been dealing with a specific raw material—north African phosphate rock—with a high content of trace metals and natural radioactive elements mainly from the 238U decay series. A disabled phosphate plant located in the vicinity of the river Tejo estuary has produced phosphoric acid for several decades (1950–1989) and dumped tons of phosphogypsum (PG) on retention lagoons, formerly decanted and deposited into a stockpile. This paper deals with the assessment of radionuclides, rare earth elements (REEs) and heavy metals transfer to plants (fam. Plantaginaceae, Plantago sp.) and mosses (fam. Bryaceae, Bryum sp.) growing naturally on the PG pile. In Plantago sp., the concentration ratio (CR, plant tissue/PG) was 0.187 for 226Ra and 0.293 for 210Pb. The translocation factor (TF, aerial parts/roots) was 0.781 for 226Ra and 0.361 for 210Pb. In contradiction to the high CR, the leachability of 226Ra from PG was low, lower than 2%. The results confirmed the role of mosses as biomonitors. A high quantity of contaminants collected in its biomass confirmed the hypothesis of their significant transport by air and rain water. High concentrations of heavy metals (As, Cd, Zn, W) in samples collected on the stockpile are an evidence of their transport from former industrial zones in the surroundings and present even more important risk for public health and environment than natural radionuclides and REEs from the PG stockpile.
KeywordsHeavy metals Leachability Bryum sp. Phosphogypsum Plantago sp. Radium Rare earth elements
The C2TN authors would like to thank the enterprise Baía do Tejo S.A., owner of the Barreiro PG stockpile, for kindly allowing sampling in its premises. They also gratefully acknowledge the Fundação para a Ciência e Tecnologia (FCT) support through the UID/Multi/04349/2013 project. Finally, they wish to express their gratitude to the Laboratory of Nuclear Engineering (LEN) and the staff of the Portuguese Research Reactor (RPI) of IST for their assistance with the neutron irradiation, and the devoted collaboration of LPSR gamma spectrometry and liquid scintillation technicians Mrs. Lidia Silva and Mr. João Abrantes.
- Abril, J. M., García-Tenorio, R., Enamorado, S. M., Hurtado, M. D., Andreu, L., & Delgado, A. (2008). The cumulative effect of three decades of phosphogypsum amendments in reclaimed marsh soils from SW Spain: 226Ra, 238U and cd contents in soils and tomato fruit. Science of the Total Environment, 403, 80–88. doi: 10.1016/j.scitotenv.2008.05.013.CrossRefGoogle Scholar
- Borylo, A., Nowicki, W., & Skwarzec, B. (2013). The concentration of trace metals in selected cultivated and meadow plants collected from the vicinity of a phosphogypsum stack in northern Poland. Polish Journal of Environmental Studies, 22, 347–356.Google Scholar
- Brown, D. H. (1984). Uptake of mineral elements and their use in pollution monitoring. In A. F. Dyer & J. G. Duckett (Eds.), The experimental biology of bryophytes (pp. 229–256). New York, London: Academic Press.Google Scholar
- Dung, H. M., Freitas, M. C., Santos, J. P., & Marques, J. G. (2010). Re-characterization of irradiation facilities for k0-NAA at RPI after conversion to LEU fuel and re-arrangement of core configuration. Nuclear Instruments and Methods in Physics Research Section a, 622, 438–442.CrossRefGoogle Scholar
- El-Reefy, S. A., Attallah, M. F., Hilal, M. A., & El Afifi, E. M. (2007). TE-NORM in phosphogypsum; characterization and treatment. Waste Management Symposium. Tucson, AZ (United States); 25 Feb – 1 Mar 2007. http://www.wmsym.org/archives/2007/pdfs/7059.pdf. Accessed 29 November 2016.
- Epstein, E. (1972). Mineral nutrition of plants: principles and perspectives. John Wiley and Sons, Inc., p 412.Google Scholar
- Fernandes, A. C., Santos, J. P., Marques, J. G., Kling, A., Ramos, A. R., & Barradas, N. P. (2010). Validation of the Monte Carlo model supporting core conversion of the Portuguese research reactor (RPI) for neutron fluence rate determinations. Annals of Nuclear Energy, 37, 1139–1145.CrossRefGoogle Scholar
- Fesenko, S., Sanzharova, N., Vidal, M., Vandenhove, H., Shubina, A., Thiry, Y., Reed, E., Howard, B. J., Pröhl, G., Zibold, G., Varga, B., & Rantavara, A. (2009). Radioecological definitions, soil, plant classifications and reference ecological data for radiological assessments. In: Quantification of radionuclide transfer in terrestrial and freshwater environments for radiological assessments. IAEA-TECDOC-1616, pp. 7–26.Google Scholar
- Fesenko, S., Carvalho, F., Martin, P., Moore, W. S., & Yankovich, T. (2014). Radium in the environment. In: The environmental behaviour of radium: revised edition. IAEA-TRS-416, pp. 33–105.Google Scholar
- Glime, J. M. (2007). Nutrient relations: uptake. In: Bryophyte ecology. Vol. 1 Physiological Ecology, chapter 8–4. E-book sponsored by the Michigan Technological University and the International Association of Bryologists. http://www.bryoecol.mtu.edu/. Accessed 29 November 2016.
- Kabata-Pendias, A. (2010). Trace elements in soils and plants. 4th Edition. CRC Press, p. 584, ISBN 9781420093681.Google Scholar
- Klos, A., Rajfur, M., & Waclawek, M. (2011). Application of enrichment factor to the interpretation of results from the biomonitoring studies. Ecological Chemistry and Engineering S, 18, 171–183.Google Scholar
- Merešová, J., Wätjen, U., Altzitzoglou, T. (2012). Determination of natural and anthropogenic radionuclides in soil—results of an European Union comparison. Applied Radiation and Isotopes, 70, 1836–1842.Google Scholar
- Mihalik, J., Tlustoš, P., & Szakova, J. (2011). The influence of citric acid on mobility of radium and metals accompanying uranium phytoextraction. Plant, Soil and Environment, 57, 526–531.Google Scholar
- Prasad, M. N. V. (2008). Trace elements as contaminants and nutrients: consequences in ecosystems and human health. John Wiley & Sons, Inc., p. 778, ISBN: 978–0–470-18095-2.Google Scholar
- Prudêncio, M. I. (2009). Ceramic in ancient societies: a role for nuclear methods of analysis. In A. N. Koskinen (Ed.), Nuclear chemistry: New research (pp. 51–81). New York: Nova Science.Google Scholar
- Santos, A. J. G., Mazilli, B. P., Favaro, D. I. T., & Silva, P. S. C. (2006). Partitioning of radionuclides and trace elements in phosphogypsum and its source materials based on sequential extraction methods. Journal of Environmental Radioactivity, 87, 52–61. doi: 10.1016/j.jenvrad.2005.10.008.CrossRefGoogle Scholar
- Selinus, O., Alloway, B., Centeno, J. A., Finkelman, R. B., Fuge, R., Lindh, U., & Smedley, P. (2013). Essentials of medical geology—impacts of the natural environment on public health. Elsevier, New York, p. 832, eBook ISBN:9780080454191.Google Scholar
- Shtangeeva, I., Lin, X., Tuerler, A., Rudneva, E., Surin, V., & Henkelmann, R. (2006). Thorium and uranium uptake and bioaccumulation by wheat-grass and plantain. Forest Snow and Landscape Research, 80, 181–190.Google Scholar
- SIMARSUL (2006). Estudo de impacte ambiental da ETAR Barreiro/Moita. Resumo não-técnico. Atkins Portugal-Consultores e Projectistas Internacionais, Lda. http://siaia.apambiente.pt/AIADOC/AIA1478/RNT1478.pdf. Accessed 29 November 2012.