en Radiobiology Radiobiology تحقيق بديع Original Research <div style="text-align: justify;">Background: The presence of radon and radioactive nuclei emitted from uranium could result in a radiological hazard. Humans are exposed to natural radiation, which arises from cosmic radiation, radon gas, and radiation from radioactive nuclei of each thorium, uranium, and thorium. Methods and Methods: This research cares to study the concentration of the natural radioactivity (238-U, 232-Th and 40-K) and radon for fourteen samples of soil from different fourteen location in Wadi Hodein region in Egypt (Southern Eastern Desert). The radon gas was measured using CR-39 detector, while the activity concentration for natural radioactivity measured by HPGD system. Results: The results of the gamma ray spectroscopy show that main activity concentration of 238-U, 232-Th and 40-K are 13.04&plusmn;1.15, 12.33&plusmn;1.54 and 445.33&plusmn;23.54 Bq/Kg respectively. The 43% form concentration value for K-40 are higher than the exemption level 412 Bq/Kg proposed by the UNSCEAR 2008. Moreover, the 15% of values for absorbed dose D_ab were higher than public average 57 nGy/h. But annul effective dose values AED were less than recommended limits for the radiation which reported by UNSCEAR 2000 and 2008. The mean value concentration of radon was 265.96&plusmn; 25.45 Bq/m³. The results of samples show that 28.27% of the radon gas concentrations and annul effective dose from radon (AED_R) in soil is higher than allowed limit recommended from International Commission on Radiological Protection agency (ICRP 2007). Conclusions: Radium, shows good relationship with radon exhalation rate in soil. Good correlation observed between lung cancer per year per million people and radon concentrations for all soil samples.</div> Radiological hazard, natural radioactivity, SSNTDs, HPGD. 719 727 http://ijrr.com/browse.php?a_code=A-10-2188-47&slc_lang=en&sid=1 E.H. EL-Araby 7900319475328460020317 7900319475328460020317 No Department 1Physics Department, Faculty of Science, Jazan University, 2097 Jazan, Saudi Arabia D.H. Shabaan doaa.hassantaha@women.asu.edu.eg 7900319475328460020318 7900319475328460020318 Yes Physics Department, University College of Samtah, Jazan University, Jazan, Saudi Arabia Z. Yousef 7900319475328460020319 7900319475328460020319 No Physics Department, Faculty of Women for Art, Science and Education, Ain Shams University, Cairo, Egypt