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Oyebog S.A.,University of Buea | Ako A.A.,Hydrological Research Center Yaounde | Nkeng G.E.,National School of Public Works | Suh E.C.,University of Buea
Journal of Geochemical Exploration | Year: 2012

In this study, 8 bottled water brands sold in Cameroon were analyzed for 76 elements/parameters by ICP-MS, IC, titration and mass spectrometric methods. This was to investigate the geochemical characteristics of the bottled waters in order to identify the main hydro geochemical processes controlling their chemical content. A comparison of the element concentrations and the legal limits for both bottled and tap water (Cameroon, EU, US EPA, WHO) shows that Aluminium concentration in three brands is above the lower guideline value set by EPA with very high lead concentration (6.4μg/l) in one brand. Various water quality classification systems were used in to characterize the different bottled water types. Piper diagram was used to establish that dominant chemical types of the bottled water brands are Ca-HCO 3, Ca-Mg-HCO 3, Ca-Na-Mg-HCO 3, Na-HCO 3 and Na-Mg-HCO 3. Application of R-Mode factor analysis to the data set allowed the determination of the possible relationship between the distribution of individual elements and lithology or other surface enrichment phenomena. In particular waters draining through volcanic rocks are enriched in elements such as As, B, Br -, Cl -, Cs, F, K, Li, Na, NO 3 -, PO 4 3-, Rb, Sc, SiO 2, Sr, Te, Ti, and V. One of the three R-Mode factor analysis associations, recognized as being representative of elements analyzed shows high nitrate and Pb loadings along with As, PO 4 3- and Zn. The latter association probably reflects a sign of anthropogenic contribution in the volcano-sedimentary aquifers of the study area. Q-Mode hierarchical cluster analysis established four major groups amongst the bottled water brands. Stable water isotopes (δD and δO 18) established that the recharge origin of the bottled waters and other groundwaters of the study area is meteoric. © 2011 Elsevier B.V.

Ako A.A.,Kumamoto University | Ako A.A.,Hydrological Research Center Yaounde | Shimada J.,Kumamoto University | Hosono T.,Kumamoto University | And 5 more authors.
Environmental Geochemistry and Health | Year: 2012

Groundwater is the only reliable water resource for drinking, domestic, and agricultural purposes for the people living in the Mount Cameroon area. Hydrogeochemical and R-mode factor analysis were used to identify hydrogeochemical processes controlling spring water quality and assess its usability for the above uses. Main water types in the study area are Ca-Mg-HCO3 and Na-HCO3. This study reveals that three processes are controlling the spring water quality. CO2-driven silicate weathering and reverse cation exchange are the most important processes affecting the hydrochemistry of the spring waters. While tropical oceanic monsoon chloride-rich/sulfate-rich rainwater seems to affect spring water chemistry at low-altitude areas, strong correlations exist between major ions, dissolved silica and the altitude of springs. In general, the spring waters are suitable for drinking and domestic uses. Total hardness (TH) values indicate a general softness of the waters, which is linked to the development of cardiovascular diseases. Based on Na %, residual sodium carbonate, sodium adsorption ratio, and the USSL classification, the spring waters are considered suitable for irrigation. Though there is wide spread use of chemical fertilizers and intense urban settlements at the lower flanks of the volcano, anthropogenic activities for now seem to have little impact on the spring water quality. © 2012 Springer Science+Business Media B.V.

Victorine Neh A.,University of Buea | Ako Ako A.,Hydrological Research Center Yaounde | Richard Ayuk A.,University of Buea | Hosono T.,Kumamoto University
Journal of African Earth Sciences | Year: 2015

The pollution potentials of the aquiferous formations in Douala was obtained by evaluating the aquifer vulnerability. Aquifer vulnerability is an intrinsic property of groundwater which gives the possibility of percolation and diffusion of contaminants from the ground surface into the subsurface. Aquifer vulnerability to pollution was evaluated for the phreatic aquifer in Douala using the DRASTIC method. DRASTIC is a groundwater quality model representing; Depth to Water, Net Recharge, Aquifer Media, Soil Media, Topography, Impact of vadose Zones, and Hydraulic Conductivity. From data, five thematic maps were generated and an intrinsic vulnerability map was developed based upon calculations of DRASTIC Indices (D.I). The D.I for the different inhabited quarters were; Bonamoussadi (BS) = 145, Bali (BA) = 138, Bonapriso (BP) = 140, Airport(AP) = 129, Ndogbong(ND) = 120, Bepanda(BE) = 130, Vallee Besengue (VB) = 134, New Bell (NB) = 125, Bonassama BM) = 128 and Rail(RA) = 167. ArcGIS quantile classification subdivided the area into four groups; very low, low, moderate and high ground water vulnerability risk zones covering about 30%, 30%, 20% and 20% of the study area respectively. An in-depth study is recommended to give a detailed perspective to the evolution and nature of actual pollution in the area. © 2014 Elsevier Ltd.

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