Assessment of natural radionuclides and heavy metal concentrations in marine sediments in view of tourism activities in Hurghada city, northern Red Sea, Egypt

Abstract

The specific activity of 40K, 232Th and 226Ra in marine sediment samples collected from National Institute of Oceanography and Fisheries (NIOF) and Safier Hotel area in Hurghada city (the most important regions in Egypt), were measured by gamma ray spectrometry using NaI(Tl) detector. The values of specific activity varied from 7 ± 1 Bq kg-1 to 53 ± 4 Bq kg-1, 6 ± 1 Bq kg-1 to 32 ± 6 Bq kg-1, and from 167 ± 11 Bq kg-1 to 1120 ± 63 Bq kg-1 for 226Ra, 232Th and 40K, respectively. The heavy metals have been measured and analysed by atomic absorption spectrometer. The major range values of heavy metals concentrations in marine sediment samples were: Cu (10.5-78.0 μg g-1), Zn (21-150 μg g-1), Pb (30-53 μg g-1), Cd (2.50-4.00 μg g-1), Fe (5100-13150 μg g-1), Mn (118-298 μg g-1), Ni (17-36 μg g-1) and Co (16-18 μg g-1). The total organic matter (TOC) and carbonates (CaCo3) distribution have been measured at some locations. Also, the frequency distribution and the value of (232Th/226Ra), (232Th/40K) and (226Ra/40K) ratio for all measured samples were determined. Additionally, evaluations have been made of the radiological hazards and the results are diagrammed by Surfer program in maps.