Natural radionuclides in trees grown on a uranium mill tailings waste pile



The purpose of the study was to investigate natural radionuclide uptake and allocation by trees.

Materials and methods

Samples from six Scots pines (P. sylvestris), six Norway spruces (Picea abies) and one sycamore maple (Acer pseudoplatanus) tree, growing on the Boršt uranium mill tailings waste pile in Slovenia were collected. 238U, 230Th, 226Ra and 210Pb activity concentrations in wood, shoots and 1-year-old needles or leaves were determined. Particular radionuclides were separated from the samples by appropriate radiochemical procedures and their activity concentrations measured with an alpha spectrometry system. In addition, concentration ratios for different plant parts were calculated.

Results and conclusions

Results showed that for all radionuclides, the highest activity concentrations were found in foliage, followed by shoots and wood. The activity concentrations in trees were from 0.01 to 5.4 Bq kg−1 for 238U, 0.03–11.3 Bq kg−1 for 230Th, 2.7–2,728 Bq kg−1 for 226Ra and 5.1–321 Bq kg−1 for 210Pb. All activity concentrations were calculated on dry weight basis. The calculated concentration ratios were from 1.05E-5 to 5.39E-3 for 238U, 7.65E-6–2.88E-3 for 230Th, 3.10E-4–3.16E-1 for 226Ra and 6.70E-4–4.22E-2 for 210Pb.

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We would like to thank the staff of the Rudnik Žirovski vrh Company for their cooperation and assistance. The financial support of the Slovenian Research Agency (Grant No. P2-0075) is highly appreciated.

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Correspondence to Borut Smodiš.

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Responsible editor: Elena Maestri

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Štrok, M., Smodiš, B. & Eler, K. Natural radionuclides in trees grown on a uranium mill tailings waste pile. Environ Sci Pollut Res 18, 819–826 (2011).

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  • Natural radionuclides
  • Pinus sylvestris
  • Picea abies
  • Acer pseudoplatanus
  • Uranium mill tailings
  • Alpha spectrometry