Ayman A. El-Gamal

Department of Marine Geology, Coastal Research Institute (CoRI), National Water Research Center, (NWRC), 15 St., Elpharanaa, Elshalalat 21514, Alexandria, Egypt
Author    Correspondence author
International Journal of Marine Science, 2014, Vol. 4, No. 35   doi: 10.5376/ijms.2014.04.0035
Received: 16 May, 2014    Accepted: 30 May, 2014    Published: 17 Jun., 2014

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

El-Gamal A.A., 2014, Assessment of Natural Radioactivity Distribution in Surface Sediments at Erosion and Accretion Sites of Nile Delta Coastal Profiles, Egypt, International Journal of Marine Science, Vol.4, No.35 (doi: 10.5376/ijms.2014.04.0035)

The Nile Delta coast is highly active dynamical coastal processing area. The investigation of gamma emitters of the surface sediments collected from Nile Delta coastal profiles revealed that the distribution of the detected natural radioactive materials is dependent mainly on the coastal processes. The average concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K in the Nile Delta coastal profiles were 23.78±8.54, 23.95±11.79 and 280.93±68.19 Bq/kg, respectively. These average values are lower than the worldwide averages but still within its ranges. The concentrations of the heavy radionuclides ²²⁶Ra and ²³²Th were found higher in erosion sites compared with the accretion ones. On the other hand, the light radionuclide ⁴⁰K was behave as reverse as the heavy radionuclides that its concentration values detected at the erosion sites were lower than at the accretion ones. Radium equivalent index calculation indicated that all the sediments under investigation can use safely as building materials. The average of the outdoor gamma dose rate was 37.25±9.58 nGy/h and the annual external effective dose was 0.05±0.01 mSv/y and these values were in agreement with the corresponding values at different parts of the world. The distribution of the detected natural radionuclides and grain size in the coastal sediments at surf, breaker and offshore zones has been discussed. 

Natural radioactivity; Coastal erosion; Nile Delta; Radium equivalent index; Gamma dose; Grain size