Abstract
The mean activity concentrations of Ra-226, Th-232, and K-40 in Eshidiya phosphogypsum samples were measured as 351.4 +/- A 23.4, 3.8 +/- A 0.3, and 120.7 +/- A 8.3 Bq kg(-1), respectively. The results show that the mean values of activity concentration of Ra-226, Th-232, and K-40 are in the lower range of typical values reported for phosphogypsum samples collected worldwide. Radiological hazard indices such as the radium-equivalent activity (Ra-eq), the gamma index (I (gamma) ) alpha index (I (alpha) ), the absorbed gamma dose rate (D (in)), and the corresponding annual effective dose (E (in)) were assessed for building materials for dwellings. The results of assessment exhibit that all phosphogypsum samples are higher than the recommended safe limit for building materials for dwellings, except for the radium-equivalent activity (Ra-eq). Overall assessment, it can be concluded that the possibility of using Eshidiya phosphogypsum in building materials in proportions lower than 100 % will be safe. The mixture of phosphogypsum with normal gypsum can dilute the concentrations of natural radionuclides allowing the use of the mixed building materials to be safe from a radiological point of view.