This study aimed to determine the concentration of natural radionuclides, the chemical composition, and the geological provenance of sand samples from seven large quarries within the Douala Basin and surrounding locations within the Littoral Region of Cameroon along the Gulf of Guinea. The analyses were undertaken on a total of 24 samples, using both gamma-and X-ray spectrometry techniques. Gamma spectrometric results indicated that the samples from the study area contained amounts of natural radioactivity that are less than the globally agreed safe limits. X-ray fluorescence spectrometry yielded quantitative major, minor, and trace element concentrations that were used in tectonic discrimination diagrams, indicating that these sediments were deposited in a passive margin environment. These concentration and natural radionuclide radioactivity level data provide a reference database for this region of Cameroon as well as for the wider Gulf of Guinea.

The objectives of the present work were to characterize the investigated soil using EDXRF and to evaluate the radioactivity concentration of the primordial radionuclides using gamma-ray spectrometry-based High Purity Germanium (HPGe) detector, Broad energy type (BEGe). Soil characterization using EDXRF in the present study gives an overview of the geological origin or provenience of the investigated area. As a result, the analyzed soil samples can be classified chemically as Fe-soil and are illustrative dregs from the Continental margin because of high concentration of Fe (its concentration ranged from 14.78% to 22.26%) in all the investigated samples. The plotting of Al 2 O 3 /SiO 2 (%) as a function of Fe 2 O 3 and MgO (%) for the eighteen sample points investigated from Douala and the diagram for the tectonic discrimination of sediment provenance evidenced that all soil samples are residue from Passive margins. The observed activity concentration profile of the primordial radionuclides and the calculated radium equivalent activity show that no significant radiological risk can be observed for inhabitants within the study areas. As regards to that, the obtained results of the two analytical techniques could be viewed as baseline data for subsequent investigations on elemental characterization and radioactivity assessment in the study area.

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