Drinking water requires excellent physico-chemical quality. It must therefore not contain any substance which is harmful, or which may harm the health of the consumer. The drinking water supply of Bangeli canton (Togo) is provided by ground water and surface water which have been polluted by several industrial discharges as a result of Togo’s intensive industrialization in the last few decades. In order to contribute to the control of drinking water in this locality, our study focused on the state of metal pollution in the waters of this canton. To assess the spatiotemporal evolution of the metallic contamination in Bangeli waters, surface and groundwater samples were taken during dry and rainy seasons in the last three years. This comparative study will allow for a more in-depth assessment of the study area. These samples were analysed by ICP-MS for heavy metals such as Fe, Pb, Cr, Zn, Cu, Co, As, Mn, Sb, Ni, and Cd. The mean values obtained for these metals from groundwater are, respectively, 1144.87; 2.53; 3.42; 3.63; 6.49; 0.69; 143.76; 160.03; 5.67; and 0.036 µg/L. Except for Fe, Sb, and Mn, all the other metals have values below WHO guidelines. The heavy metal pollution index (HPI) applied to these waters gave values between 31.49 and 307.51, with 88.66% of samples below the limit value (100). Health risk assessment factors, including average daily doses, hazard quotient, carcinogenic risks, and hazard index indices, were computed for children and adults. Finally, the HPI index of Fe and Sb in both child and adult cases showed a value greater than the safe limits, which causes harmful health hazards and potential non-carcinogenic health risks to humans. However, carcinogenic risk for Cr, Cd, Pb, and As is less than the limit value (10⁻⁴), indicating that there is no risk of cancer. The interpretation of PCA results made it possible to understand that mining has contributed to the pollution of some water resources in Bangeli, and cluster analysis (CA) applied to the data showed that the sampling points can be grouped into four groups, which were primarily formed by extravagant concentrations of Fe, Mn, Cu, and Sr.

Background: This work focused on the valorization of cashew apple, which, when ripe, rot in plantations in Togo despite its richness in vitamin C and other nutrients. The aims were to produce and characterize cashew apple powder. Methods: In this study, six different of cashew apple powder were made. After the process of picking, sorting, washing, steam bleaching for 15 minutes or not, cutting into rounds, drying at 45-50°C in the oven or in the sun, grinding was carried out. The powders were sealed and stored in polyethylene bags at temperatures between 30 and 32°C. The physico-chemical characteristics were determined by titrimetry and atomic absorption spectrophotometer. Result: The moisture content of the powders varies from 10 to 11% with a yield ranging from 22.52 to 28.12%. The vitamin C and protein content obtained ranged from 688.7 to 924.5 mg/100 g (12.83 to 15.33%) respectively. The fiber content from 7.48% to 7.83%. Two powders retained a light yellow color more visibly than the other powder which are a little darker.

The increasing use of untreated pig slurry as an organic amendment in Kozah 1 (Togo) raises environmental and public health concerns. A preliminary survey revealed that 80% of farmers apply raw slurry directly to crops, while 20% discharge it into the environment, from where it is often collected by market gardeners. This study assesses the fertilizing potential and toxicity risks associated with such practices. Samples were collected from ten randomly selected pig farms in Lama canton, a zone dominated by small-scale artisanal pig farming. In each pit, stratified sampling targeted the surface, middle, and bottom layers using a sterile bucket mounted on a 1.5-meter pole. Each layer (500 mL) was homogenized into a composite sample per site. Samples were kept at 4°C until physico-chemical and microbiological analyses. The slurry showed a high organic matter content (730 ± 1.1 g/kgDM) and macronutrients (N = 21 ± 0.2, P₂O₅ = 25 ± 0.2, K₂O = 38 ± 0.4 g/kgDM), but a low C/N ratio (5.2), indicating instability. Pathogens (E. coli, Salmonella) and elevated nitrate and phosphate levels were also detected, suggesting health and water pollution risks. The findings underscore the need for pretreatment methods such as co-composting to reduce pathogenic loads and stabilize nutrients for safer agricultural use.

La recherche de gypse dans les déchets phosphates issus du traitement du minerai de phosphates de Hahotoé-Kpogamé a été réalisée dans le but de réduire les impacts polluants et de valoriser au moins en partie ce qui peut l’être dans ces déchets. Les caractérisations physicochimiques ont révélé la présence des ions sulfate et du calcium dans ces déchets. Les teneurs des ions sulfate et du calcium sont respectivement de l’ordre de 1,5 % et 10 %. Les analyses par diffraction des rayons X et les analyses thermiques différentielle (ATD) et thermogravimétrique (ATG) ont permis de conclure que l’existence des ions sulfate et du calcium dans les déchets est due en partie a la présence du gypse.

One of the consequences of the improvement of the living conditions of the populations is the strong demand in thermal energy for the households whereas in the developing countries, the cost of living is a brake with all the social layers to reach supply of butane gas for their energy needs. This study takes place in the context of energy, environmental and sanitation challenges in the city of Sokodé. Indeed, we are witnessing more and more growing needs for butane gas, firewood or charcoal for cooking or lighting in the city of Sokodé as everywhere in other cities of the same size. Thus by the production of energy in situ, the condition of the populations will be able to improve significantly thanks to the recovery of sludge and fermentable fractions of solid waste into biogas. The objective of this work is to produce and recover methane from fermentable waste produced in the city of Sokodé. The methane or biogas recovered will be used as fuel to fuel kitchens in households. The resulting digestate will serve as an organic amendment to agricultural soils in the commune of Sokodé. Laboratory scale tests have been carried out to validate the value of co-digestion of sewage sludge with fermentable solid waste. The results obtained have shown that the methanogenic potential of sewage sludge is low compared to that of fermentable solid waste. The co-digestion of the two products allows a greater production of methane representing an energy gain compared to the methanisation of the sewage sludge alone. This study shows that waste (sludge from public septic tanks, waste from markets, hotels and fermentable households) can be considered an appreciable energy resource. Their Co-treatment would, while reducing the nuisance associated with this waste, produce valuable energy.