Background: : Due to the difficulties of locally obtaining ZnS(Ag), preliminary investigation of the radioluminescence characterization of Zinc oxide (ZnO) for alpha particle detection was performed. Materials and Methods: The scintillation properties of ZnO films were tested using alpha sources                     (Am-241). The correlations between ZnO scintillation responses and irradiation time and source activity were also verified and compared with the response of a ZnS(Ag) detector. Results: The obtained results showed that the response of ZnO was linear with the exposure time, and the uncertainty of the repeatability was less than 1%. In addition, ZnO was found to have good radiation resistance over a wide range of doses. Conclusion: The preliminary results may be indicative that the proposed ZnO detector could be considered as a promising detector for alpha particles.

 

Background: Since the radionuclides concentration in teeth is a good indicator of the human body’s radioactive contamination, the purpose of this study was to measure the track density of alpha particles emitted from the human teeth and to assess the resulting cancer risk. Material and Methods: In this cross-section study, 93 permanent and unfilled tooth samples were collected from the patients residing in Khorramabad, Iran, and visiting dental clinics in this city. The alpha track density for the tooth samples was measured using CR-39 nuclear track detector. Annual effective dose (AED) and excess lifetime cancer risk (ELCR) were estimated based on the recommendations made by ICRP and UNSCEAR. Results: The mean alpha track density from ²²²Rn in patients’ teeth was410.15 tracks cm^-2, whereas the mean for women and men equaled 441.42 and 378.20, respectively. This difference was not statistically significant (P=0.22), but there was a statistically significant difference between the track densities in different age groups (P˂0.001).In this study, the average radon activity concentration was 40.62 Bq m^-3. Also, the mean annual effective dose and the mean ELCR were calculated as 1.02 mSvy^-1 and 3.59 ×10^-3, respectively. Conclusion: The AED value was higher than the permissible dose limit and also the mean ELCR was higher than the global average. Based on the results, it is necessary to perform periodical monitoring to detect pollution sources.

Background: This study focuses on the uranium concentration (UC), radium content (RC) and radon exhalation rates (RER) in selected food crops consumed in Babil governorate, in the centre of Iraq. Materials and Methods: Neutron activation technique and sealed cup with CR-39 alpha track detector were used respectively to investigate the natural radioactivity of selected food crops collected from Babil governorate, Iraq. Results: In the current study, the highest UC was found to be 0.0346 ppm in the turnip crop, whereas the lowest value of UC (0.0142 ppm) was found in grape crop. The highest RC was found to be 0.651 Bq/kg in turnip, while the lowest RC (0.169 Bq/kg) was found in the fig crop. The values of RER ranged from 0.016 Bq/m².h found in the fig to 0.065 Bq/m².h found in the turnip. Conclusion: The levels of UC in food crops were lower than 1.7 ppm, the recommended limits of UNSCEAR. A strong direct correlation was found between the UC and RC in selected food crops.