Assessment of Natural Radioactivity and Radiological Risks in River Sediments from Calabria (Southern Italy)
Open Access
- 14 February 2021
- journal article
- research article
- Published by MDPI AG in Applied Sciences
- Vol. 11 (4), 1729
- https://doi.org/10.3390/app11041729
Abstract
This study was developed to carry out a comprehensive radiological assessment of natural radioactivity for river sediment samples from Calabria, southern Italy, and to define a baseline background for the area on a radiation map. In the studied area, elevated levels of natural radionuclides are expected, due to the outcropping acidic intrusive and metamorphic rocks from which the radioactive elements derive. To identify and quantify the natural radioisotopes, ninety river sediment samples from nine selected coastal sampling points (ten samples for each point) were collected as representative of the Ionian and the Tyrrhenian coastline of Calabria. The samples were analyzed using a gamma ray spectrometer equipped with a high-purity germanium (HPGe) detector. The values of mean activity concentrations of 226Ra, 232Th and 40K measured for the studied samples are (21.3 ± 6.3) Bq kg−1, (30.3 ± 4.5) Bq kg−1 and (849 ± 79) Bq kg−1, respectively. The calculated radiological hazard indices showed average values of 63 nGy h−1 (absorbed dose rate), 0.078 mSv y−1 (effective dose outdoors), 0.111 mSv y−1 (effective dose indoors), 63 Bq kg−1 (radium equivalent), 0.35 (Hex), 0.41 (Hin), 0.50 (activity concentration index) and 458 µSv y−1 (Annual Gonadal Equivalent Dose, AGED). In order to delineate the spatial distribution of natural radionuclides on the radiological map and to identify the areas with low, medium and high radioactivity values, the Surfer 10 software was employed. Finally, the multivariate statistical analysis was performed to deduce the interdependency and any existing relationships between the radiological indices and the concentrations of the radionuclides. The results of this study, also compared with values of other locations of the Italian Peninsula characterized by similar local geological conditions, can be used as a baseline for future investigations about radioactivity background in the investigated area.This publication has 26 references indexed in Scilit:
- Radiological assessment, mineralogy and geochemistry of the heavy-mineral placers from the Calabrian coast (South Italy)Journal of Instrumentation, 2019
- A methodological approach to a radioactive sample analysis with low-level γ-ray spectrometryJournal of Instrumentation, 2018
- Natural radioactivity measurements and dosimetric evaluations in soil samples with a high content of NORMThe European Physical Journal Plus, 2017
- Natural radionuclides and trace elements in rice field soils in relation to fertilizer application: study of a chronic kidney disease area in Sri LankaEnvironmental Earth Sciences, 2009
- Study of the spatial distribution of natural radioactivity in the upper Egypt Nile River sedimentsRadiation Measurements, 2007
- Uptake and distribution of natural radioactivity in wheat plants from soilJournal of Environmental Radioactivity, 2005
- Gamma-ray measurements of naturally occurring radioactive samples from Cyprus characteristic geological rocksRadiation Measurements, 2003
- Edaphic and physiographic factors affecting the distribution of natural gamma-emitting radionuclides in the soils of the Arnás catchment in the Central Spanish PyreneesEuropean Journal of Soil Science, 2002
- Multi-stage Melting in the Lower Crust of the Serre (Southern Italy)Journal of Petrology, 2002
- Influence of geology and soil particle size on the surface-area/volume activity ratio for natural radionuclidesJournal of Radioanalytical and Nuclear Chemistry, 1995