Natural radionuclides in groundwater from Qena governorate, Egypt

Abstract

AlphaGUARD radon gas analyzer and NaI (Tl) spectrometer were used to measure the concentration levels of 222Rn and, 226Ra, 232Th, and 40K respectively in 109 groundwater samples collected from four different districts in Qena governorate, Egypt. The average values of the activity concentration were 3.57 ± 0.08, 0.54 ± 0.03, 0.40 ± 0.03, and 5.10 ± 0.44 Bql−1 for 222Rn, 226Ra, 232Th, and 40K, respectively. The average values of 222Rn, 226Ra, and 232Th are lower than, 100, 1, and 1 Bql−1, respectively, the WHO recommended permissible levels for drinking water. For radiation exposure assessment, the annual effective doses due to ingestion of 226Ra and 232Th and inhalation of 222Rn for adults were determined and compared with the reference limits. The annual effective doses due to ingestion 139.21–201.34 µSvy−1 are higher than the public annual dose limit 100 µSvy−1 recommended by WHO. These indicate that the ingestion of groundwater from the study areas might pose radiological health hazards.