Water supply, sanitation and health risks in Douala 5 municipality, Cameroon.

BACKGROUND: In the poor zones of sub-Saharan Africa, the conventional drinking water network is very weak. The populations use alternative groundwater sources which are wells and springs. However, because of urbanization, the groundwater sources are degrading gradually making pure, safe, healthy and odourless drinking water a matter of deep concern. There are many pollutants in groundwater due to seepage of organic and inorganic pollutants, heavy metals as well as microbiological contamination. This study was carried out in October 2012 and aimed to analyze the practices and behaviors of populations related to water supply that may constitute potential risks of microbiological contamination and emergence of waterborne diseases. METHOD: This study was carried out on a sample of 285 households, distributed in twelve principal quarters of the Douala V municipality in Cameroon. After data collection through the questionnaires, the selection of vulnerable quarters was done by the tabulation of some specific results on the questionnaire. The microbiological analysis was carried out using an innovative rapid test called "Micro Biological Survey (MBS)" that has been developed and patented by MBS srl, a recent spin-off of the University of Roma Tre. RESULT: We found out that 42.30% of households used water from drilled wells (forages), 33.80% from Cameroon National Water Company (CDE) distribution network, 9.50% from spring, and 9.40% used other source of water such as buying industrial mineral water. However, it should be noted that, as dangerous as it may be, wells ("puits" in French) water is used as permanent source of drinking water by 5% of households. In general, 63.2% of households affirmed not to have benefited the fitting of public water point. Moreover, among the quarters were the households affirmed to have benefited from the development of a public water point, 52.5% of these water point were no longer functional. From the obtained data we have assessed that 83% of wells analyzed are faecally contaminated and all the forages analyzed (100%) are not contaminated. The most affected people by water-related diseases are children under 5 years (43%). CONCLUSION: We highly recommend the City Council of Douala V to restrict the use of the contaminated wells and provide alternative water sources such as forages for public use and to ensure that microbiological quality of the new and already existing water sources is controlled regularly by the Technical Service.

Trace element differentiation in ferruginous accumulation soil patterns under tropical rainforest of southern Cameroon, the role of climatic change.

Regions under tropical rainforest cover, such as central Africa and Brazil are characterised by degradation and dismantling of old ferricrete structures. In southern Cameroon, these processes are relayed by present-day ferruginous accumulation soil facies, situated on the middle and the lower part of hill slopes. These facies become progressively harder towards the surface, containing from bottom to top, mainly kaolinite, kaolinite-goethite and Al-rich goethite-hematite, and are discontinuous to the relictic hematite-dominated ferricrete that exist in the upper part of the hill slope. These features were investigated in terms of geochemical differentiation of trace elements. It appears that, in contrast to the old ferricrete facies, the current ferruginous accumulations are enriched in transitional trace elements (V, Cr, Co, Y, Sc) and Pb, while alkali-earth elements are less differentiated. This recent chemical accumulation is controlled both by intense weathering of the granodiorite bedrock and by mobilisation of elements previously accumulated in the old ferricrete. The observed processes are clearly linked to the present-day humid climate with rising groundwater tables. They slowly replace the old ferricretes formed during Cretaceous time under more seasonal climatic conditions, representing an instructive case of continuos global change.