In-situ assessment of natural terrestrial-radioactivity from Uranium-238 ((238)U), Thorium-232 ((232)Th) and Potassium-40 ((40)K) in coastal urban-environment and its possible health implications

The risk of natural terrestrial radioactivity on human health is often underestimated, and environmental safety awareness is necessary. Hence, this study aims to assess natural sources of gamma radiation emitter in coastal urban-environment using the radiometric technique. The dosage of gamma radiation from a parent radionuclide such as Uranium-238 ((238)U), Thorium-232 ((232)Th) and Potassium-40 ((40)K) and were measured using portable gamma spectroscopy. The result showed that the measured value of (238)U activity was between 10.81 [Formula: see text] 0.69 and 46.31 [Formula: see text] 1.43 Bqkg(−1). The mean value was estimated to be 35.44 [Formula: see text] 0.97 Bqkg(−1) which is slightly higher than the world average. Meanwhile, (232)Th activity ranges from 28.42 [Formula: see text] 1.12 to 69.43 [Formula: see text] 1.76 Bqkg(−1) with the calculated mean value of 92.57 [Formula: see text] 1.17 Bqkg(−1) while (40)K activity ranged between 31.30 ± 1.32 and 328.65 ± 2.32 Bqkg(−1) with the estimated mean 137.59 [Formula: see text] 2.42 Bqkg(−1). Radiological parameters such as radium equivalent (R(eq)), internal hazard (H(int)) and external hazard (H(ext)) assessment were in the range of 66.00 Bqkg(−1) to 141.76 Bqkg(−1), 0.232 to 0.452 and 0.178 to 0.383, respectively. The measured values of gamma dose-rates ranged between 54.283 ± 0.78 and 117.531 ± 1.14 nGyh(−1) with the calculated mean value of 84.770 ± 0.97 nGyh(−1).