Natural radioactivity levels for selected kinds of Egyptian sand

The monitoring and evaluation of natural radioactivity content of sixty-five different samples of sand used in building materials, black sand and its components, and therapy sand collected from different locations in Egypt have been investigated. The specific radioactivity concentration of 238U, 232Th series, and 40K were measured by gamma-ray spectrometer using a shielded HPGe. The obtained results of 238U and 232Th series as well as 40K are discussed. The absorbed dose rate of gamma radiation ranged from 15.1 to 64.1, 9.3 to 109, 751, and 32.9 to 63.4 nGy h(-1) for sand used in building materials, black sand with its components, and therapy sand samples, respectively. The representative external hazard index (H ex) for the corresponding values are also estimated and tabulated. The present results are compared with other data previously obtained from different sand areas in both Egyptian and foreign locations.