Assessment of Pollution and Identification of Sources of Heavy Metals, and Radionuclides Contamination in Sand along the Southern Part of the Cameroonian Coast (South-West, Africa)

Francis Temgo Sopie

Department of Earth Sciences, University of Dschang, P.O. Box: 67, Dschang, Cameroon

Victorine Ambassa Bela

Department of Earth Sciences, Faculty of Science, University of Yaoundé I, Cameroon

Armel Zacharie Ekoa Bessa

Department of Earth Sciences, Faculty of Science, University of Yaoundé I, Cameroon

Archange Duviol Tsanga

Department of Earth Sciences, Faculty of Science, University of Yaoundé I, Cameroon

Patrice Roland Liyouck

Department of Earth Sciences, University of Dschang, P.O. Box: 67, Dschang, Cameroon

Théophile Njanko

Department of Earth Sciences, University of Dschang, P.O. Box: 67, Dschang, Cameroon

Gabriel Ngueutchoua

Department of Earth Sciences, Faculty of Science, University of Yaoundé I, Cameroon


Copyright © 2022 Author(s). Published by Nan Yang Academy of Sciences Pte. Ltd.

Creative Commons LicenseThis is an open access article under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) License.


Sandy sediments collected along the southern part of the Cameroonian coast have been analyzed geochemically by ICP MS methods to investigate the distribution characteristics, contamination levels and related ecological risks. In these sediments, the concentration (mg/kg) of selected elements are in order Fe > Mn > Cr > V > Th > Ni > U > Co. Indices of pollution such as index of geoaccumulation, where values of all elements in the sediments were < 0, except Th in the sediments station of Yoyo II, and Cr in sediment of all stations were Igeo > 0. The contamination factor shows that the station of Yoyo II has values of CF < 1, such as Fe, V, Ni and Co. While Uranium, Th and Mn values vary from 1 to 3 and 3 to 6, and for Cr values of CF > 6. However, Kribi and Campo stations show that all the elements have values of CF < 1, except Cr which has values of CF > 6. The degree of contamination values ranges between (9.48-37.13) for the station of Yoyo II, (8.84-17.62) for the Kribi station, and (6.52-13.56) for the Campo station. The pollution loading index values at all sampling stations are lower than 1. The potential ecological risk (Er and RI), indicates that this coastal area is a low risk region. Pearson correlation, cluster analysis and principal component analysis supported that heavy metals (Fe, Mn, Cr, V, Ni and Co) have common human influences while radionuclides (Th and U) have a natural source. The presence of human activities such as domestic waste, intensive farming and the processing of industrial products could be potential sources of anthropogenic environmental pollution, thereby threatening the environmental concerns of the entire study area.

Keywords: Pollution indices; Statistical analysis; Ecological risk; Heavy metals and radionuclides; Source identification


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