English Abstract
Abstract:
The rapid industrial and technological development in our contemporary era has
imposed a worrying reality on people exposed continuously in their dwellings of
civilized societies to increasing doses of ionizing radiation emitted from naturally
radioactive materials in building materials. Especially materials that are widespread
globally and used internally in large quantities for decorating civilized buildings, like
in the kingdom of Bahrain(Bahrain), increasing the chances of exposure and absorbed
doses to their occupants. Specifically, granite, marble, and ceramic that used as tiles.
Thus, this study aims to assess the radioactivity level and the radiological hazards of
commonly used types of these materials in Bahrain's dwellings.
In this study, the specific activity concentration of primordial radionuclides
226Ra, 232Th, and 40K in these types was evaluated by the y-spectroscopy system. Its
HPGe detector was of 40% efficiency and 1.87KeV energy resolution at gamma line
energy 1333KeV of the radionuclide 60Co. The study included (45) imported and
commonly used tile-type samples of them used for decoration of dwellings. The
samples of these types were randomly selected based on statistical analysis of data
collected through field survey interviews conducted in the commercial local market.
Before measuring the study's samples, the HPGe detection system was calibrated by
certified mixed standard sources sample (NG2-223) of 11 radionuclides covering the
gamma energy ranges between (88-1836) keV. Also, it is validity was tested by certified
reference (IAEA-447), where its accuracy of measurement reached 96.77%.
The results of the study showed that the average of the measured specific
radioactivity concentrations, in Bq/kg, of the radionuclides (226Ra, 232Th, and 40K) for
granite, marble, and ceramic were found to be (43.36, 59.65, and 797.00), (9.61, 0.99,
and 18.65), and (41.83, 46.88, and 731.57), respectively. These results were found to
be in good agreement with other international studies. In addition, a matrix of 8
radiological hazard indices was estimated for the studied types including the Radium
equivalent index, Gamma index, Alpha index, Internal and External hazard indexes,
Absorbed dose rate index, Annual effective dose equivalent, and Excess lifetime cancer
risk index. The study revealed, according to the agreement of the averages of studied
types with international safety limits on these indices, that marble is the highest (100%),
then ceramic (88%), and granite is the lowest (75%). Therefore, most types of
investigated building materials do not pose radiological hazards, and residents can
safely use them in their dwellings, except for some determined granite and ceramic
samples that may require preventive measures.
Finally, the study provides several practical benefits and recommendations as
promoting building and health sustainability through using eco-friendly materials,
including a "radiative fingerprint" in product assessments for safety and quality. Also,
further studies are recommended for other material types that contribute to setting a
radiological baseline map for Bahrain.
Keywords: Radiological hazards, gamma-spectroscopy, HPGe detector, building
materials, Bahrain.
