Natural radioactivity levels and radiological implications in the high natural radiation area of Wadi El Reddah, Egypt

Wadi El Reddah, Egypt, is mostly enclosed by scattered exposure to the chronological sequence of a metavolcanic and metagabbro-diorite complex. There are radiological impacts due to internal and external exposure to the high natural background radiation caused by 226 Ra, 232 Th, and 40 K in the Wadi El-Reddah stream sediments. 72 samples were collected and the activity concentration was measured using a NaI(Tl) gamma-spectroscopy system. The average activity concentration of 226 Ra, 232 Th and 40 K was 215 ± 118 Bq kg −1 , 131 ± 90 Bq kg −1 and 822 ± 125 Bq kg −1 , respectively. Most of the studied samples had a higher activity concentration than the world average.