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Bioaccumulation of uranium from waste water using different strains of Saccharomyces cerevisiae

Tykva R., Novák J., Podracká E., Popa K.

Nukleonika

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2009

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Vol. 54, No. 2

143-148

EN

Five different strains of Saccharomyces cerevisiae were tested for their abilities to accumulate uranium from waste water containing competitive ions. Samples of water passing out from a previous uranium mill were used. The strains tested possess different abilities to accumulate uranium. The kinetics of bioaccumulation, the leaching degree, the influence of cell density and their origin were investigated. Under the applied experimental conditions, more than a half of the total activity (uranium and the decay products) could be accumulated after 60 min contact time of 1 mL S. cerevisiae suspension and 5 mL of water. The other cations present in solution effectively competed for the uranium accumulation. 226Ra and its decay products were completely retained using all tested strains.

2

Bioaccumulation of 226Ra in the plants growing near uranium facilities

Tykva R., Podracká E.

Nukleonika

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2005

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Vol. 50,suppl.1

25-27

EN

Radiopollution of soils in the close neighbourhood of a uranium mine and a uranium mill was characterized using measurement of specific 226Ra activity by gamma spectrometry. It was found that it ranged from values lower than the admissible limit of 0.2 Bq.g 1 of soil (averaged over the first 15 cm below the ground surface) to values more than one hundred times higher. Bioaccumulation of 226Ra from the measured soils in plant species which were naturally growing on the analysed sites was analysed. The specific 226Ra activity of aboveground dry plant parts ranged within two orders of magnitude. Currently occurring and simply collected Mentha piperita was found to be useful for biomonitoring of soils.

3

Sources of environmental radionuclides and recent results in analyses of bioaccumulation. A review

Tykva R.

Nukleonika

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2004

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Vol. 49,suppl.1

3-7

EN

In principle, there are two sources of environmental radionuclides, namely natural and man-made. In comparison with other environmental pollutants as, e.g., heavy metals, some scientific and technical disciplines profit by the natural radionuclides, using them for age determination of the samples, e.g., hydrology, geology and archaeology. Nevertheless, the environmental radionuclides represent mostly risk for a human health. Therefore, in this review, their sources are shortly described and original recent analyses of some bioaccumulation methods are presented, using either selected plant species or microorganisms, respectively. The different uptakes in all systems were measured to evaluate the possibility of application of the tested biological materials as markers of environmental contamination. It was also demonstrated that the detection methods developed for analyses of bioaccumulation of environmental radionuclides could be applied in radiotracer methodology for a study of bioaccumulation of heavy metals. While gamma spectrometry for soil samples and liquid scintillation spectrometry for water samples were used, autoradiography was applied to analyze the distribution of radionuclides during and/or after bioaccumulation.