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Huge quantities of fly ash and bottom ash are generated from thermal power plants and it presents great concern for country, mainly due to the environmental effects. In this study, fly ashes and bottom ash were characterized from technical and radiological aspects. Health effect due to the activity of radionuclides 226Ra, 232Th and 40K was estimated via radium equivalent activity (Raeq), external hazards index (Hex), the external absorbed dose rate (D) and annual effective dose rate (EDR). The specific surface area (40.25 m2 g−1), particle density (1.88 g cm−3) and LOI (23.49%) were typical for bottom ash. Siliceous fly ash contained 32% reactive silica. The annual effective dose rate for all ashes is ≤ 0.2 mSv y−1. Both, fly ash and bottom ash present potential secondary raw materials to be used for building purposes as result of their technological and radiological assessment.

Taking into account the importance of distribution and transfer of radionuclides in the soil–plant system, especially in agricultural fields, the aim of this research was assessment of radioactivity contribution and transfer characteristics of natural radionuclides in agroecosystem. The measurement of the natural radioactivity distribution was conducted in organic and sustainable farming management systems. Statistical evaluation of the physical and chemical properties of soils subjected to different farming systems, revealed the existence of differences in some parameters. Balanced distribution of natural radionuclides in soil-crop system was observed. Radionuclide 40K was the most accessible to the investigated crops via uptake from the soil, then 232Th and 226Ra. The obtained results are useful for understanding the behavior of the radionuclides and provide an insight into the cumulative deposition of radioactivity in the agroecosystem.

Taking into account the importance of distribution and transfer of radionuclides in the soil–plant system, especially in agricultural fields, the aim of this research was assessment of radioactivity contribution and transfer characteristics of natural radionuclides in agroecosystem. The measurement of the natural radioactivity distribution was conducted in organic and sustainable farming management systems. Statistical evaluation of the physical and chemical properties of soils subjected to different farming systems, revealed the existence of differences in some parameters. Balanced distribution of natural radionuclides in soil-crop system was observed. Radionuclide 40K was the most accessible to the investigated crops via uptake from the soil, then 232Th and 226Ra. The obtained results are useful for understanding the behavior of the radionuclides and provide an insight into the cumulative deposition of radioactivity in the agroecosystem.

This paper is focused on the results for activity concentrations of Be-7 in depositions recorded in Vina Institute of Nuclear Sciences, as part of radioactivity monitoring in Institute from 1994 to 2013. year. Samples were collected on a monthly basis and activities were present on sampling day (middle of the month). The activities were determined on HPGe detectors by standard gamma spectrometry, and they ranged from 0.05 to 10.4 Bq m(-2). The obtained results were statistically analyzed. The Be-7 activity shows a pronounced seasonal pattern, with the maximum in spring-summer and minimum in winter.

This work presents a comprehensive study of natural radioactivity in 720 building materials imported in Serbia in 2012. Radioactivity concentrations of Ra-226, Th-232 and K-40 in the studied samples range from LT 5 to 4,938, LT 3 to 763 and LT 10 to 3,192 Bq kg(-1), respectively. The maximum values of Ra-226 and Th-232 activity concentrations were found in zirconium mineral, while the highest K-40 activity concentration was in the feldspar. Based on the obtained radionuclide concentrations, radium equivalent activity, air absorbed dose rate, annual effective dose, external and internal hazard indices, gamma and alpha index due to radon inhalation were evaluated to assess the potential radiological hazard associated with these building materials.

This study focuses on determination of soil to plant transfer factor (TF) of long lived radionuclides Sr-90 and Cs-137. Sr-90 and Cs-137 activity concentration in agricultural soil samples was ranged between LT 0.3 and 1.3 Bq kg(-1) and 14 and 30 Bq kg(-1), from LT 2.6 to 7.2 Bq kg(-1) and 5 to 13 Bq kg(-1) fresh matter in roots and from 0.4 to 1.1 Bq kg(-1) and LT 0.2 to 0.7 Bq kg(-1) fresh matter in the rest parts of plant, respectively. Calculated values for Sr-90 and Cs-137 TF from soil to plant ranged from 0.57 to 11.2 and 0.01 to 0.43, respectively.