Evaluation de la pollution par les métaux lourds des sols et de la variété locale du maïs Zea mays dans la zone de traitement des phosphates de Kpémé (Sud du Togo)

Au Togo, le minerai de phosphate extrait à Hahotoé-Kpogamé et traité à Kpémé par l’usine SNPT libère des métaux lourds qui polluent l’environnement. L’objectif de ce travail est d’évaluer la pollution par les métaux lourds des sols et des produits agricoles (maïs) dans quatre localités situées autour de l’usine (Aglomé, Kpémé, Goumoukopé, Séouatchikopé) et dans une localité éloignée (Gbodjomé), choisie comme référence. Au total, 50 échantillons de sols et 50 échantillons de maïs ont été minéralisés par attaque aux acides et les métaux lourds dosés par spectrophotométrie d’absorption atomique. Les teneurs moyennes des différents métaux lourds analysés exprimées en ppm (mg/kg) des sols et de la variété locale du maïs Zea mays des différentes localités ont été déterminées. Les facteurs de pollution par comparaison aux normes des différents métaux lourds analysés des sols et de la variété locale du maïs des différentes localités ont été calculés. De façon générale, l’ordre décroissant de la pollution est le suivant : au niveau des localités : Aglomé > Kpémé > Goumoukopé > Séouatchikopé > Gbodjomé au niveau des sols : Cadmium > Nickel > Cuivre > Plomb au niveau du maïs : Nickel > Cadmium > Cuivre > Plomb.Mots clés : usine de phosphate, facteur de pollution, métaux lourds

Effects of pollution on oxidative stress in aquatic species: case of the fish Sarotherodon melanotheron in Bè Lagoon (Lomé)

This study aimed to assess heavy metals accumulation and oxidative stress biomarkers in the fish Sarotherodon melanotheron from a site receiving discharges from industrial and harbor activities (Bè Lagoon) and a reference or control site in Lake Togo, Togo. Atomic absorption spectrophotometry (AAS) targeting four heavy metals (lead, cadmium, copper and nickel) in the waters of Bè Lagoon showed levels of about 2.58 ± 0.11 μg/l, 1.03 ± 0.15 μg/l, 1.71 ± 0.17 μg/l and 3.03 ± 0.07 μg/l respectively for Pb, Cd, Ni, Cu. In water of the control site, only Cu and Ni were detected at lower levels: 1.54 ± 0.22 μg/l for Ni and 0.89 ± 0.18 μg/l for Cu. Furthermore, in tissues (liver, muscle and gills) of the fish, the heavy metal contents are found in larger samples of the Bè Lagoon. Among the biological parameters (oxidative stress biomarkers), the catalase activity (P < 0.0001 in liver and P < 0.005 in gill) was found to be significantly higher in the fish collected from Bè lagoon when compared with control site. These changes in biomarkers response at the subcellular level therefore indicate an impact on the biology of the fishes living in Bè lagoon.Keywords: Bè lagoon, catalase activity, Lake Togo, MDA, pollution

Assessment of pesticide residues and trace element contamination in market gardens of Togo

All intensive agriculture, like periurban agriculture, uses massive inputs such as agrochemicals. This study aims to assess the environmental impacts of agrochemical use in periurban agriculture in Togo. It was based on the chemical analyses of soil, water and vegetable samples. These analyses were carried out by gas chromatography on extracts from soil, water and vegetable samples. In soil samples, the concentrations of pesticide residues are lower than 20 ìg/kg of dry material. For water samples, contamination levels vary from 0.02 to 1.1 ìg/L of dry material with the highest levels for metalaxyl M (1.1 ìg/L) and for dimethoate (1 ìg/L). In vegetables, the concentrations measured are between 0.01 and 0.1 mg/kg of dry material. All these concentrations are affected by a positive factor of the maximum limits of residues. These agrochemicals, coupled with periurban environmental management led to the high concentrations of trace elements. Lead and cadmium concentrations in water are 10 and 21 times respectively higher than the maximum concentration allowable for drinking water by the WHO. The study showed that inappropriate use of agrochemicals in Togolese periurban agriculture creates ecological disturbances that could affect produce quality.Key words: Togo, periurban agriculture, agrochemicals, pesticide residues, trace element

Influence of Moringa oleifera leaves on atherogenic lipids and glycaemia evolution in HIV-infected and uninfected malnourished patients

Objectives: The study evaluated mineral composition of “Togolese ecotype” of Moringa oleifera leaves and its effect on anthropometric parameters, atherogenic lipids and glycaemia during nutritional recovery in HIV negative and HIV positive malnourished patients after daily use of the leaves powder. Methodology and results: Patients aged from 12 months to 8 years, consumed every day for 15 weeks the leaves powder. Results showed that powder is rich in proteins, micronutrients and induced BMI increase in both patients (p C 0.001). Biochemical parameters determination showed decrease in total cholesterol, triglycerides, LDL-cholesterol (p C 0.01), atherogenicity index (AI) correlated with HDL-cholesterol increase (p C 0.001) in HIV negative. Increase in triglycerides, LDL-cholesterol, AI (p C 0.001) correlated with HDLcholesterol decrease (p C 0.001) is observed in HIV positive. Total cholesterol decreased more in HIV positive asymptomatic and increased in patients treated with ARV drugs (p C 0.0001). Glycaemia level is decreased in both patients of the study. Conclusion and application of findings: This study confirms higher concentrations of proteins, micronutrients, hypolipidemic potential and hypocholesterolemic activity of M. oleifera leaves. This explained nutritional recovery and reduction of atherogenic lipids. Positive effect of the powder on cholesterol metabolism is due to beta-sitosterol, bioactive phytoconstituent of the leaves which fixed LDL particles and thought to be through the lowering significantly of their plasma concentrations. Reduction of glycaemia in both patients confirms also hypoglycemic properties of leaves with high concentration of polyphenols and antioxydants. The lowering of atherogenic risk and glycaemia after regular consumption of M. oleifera leaves powder is more significant in HIV negative than HIV positive patients. Results of this study bring information which will make it possible to pediatrics and nutritionists to adapt better use of M. oleifera leaves to combat malnutrition and the follow-up of HIV positive persons and in particular those on antiretroviral treatment. Key words: Moringa oleifera, malnutrition, atherogenic lipids, glycaemia, HIV/AIDS

Les Fractures De La Patella Chez L’adulte

Objectives: to determine the epidemiological aspects, the different techniques of surgical fixation of the patella fractures and the results. Patients and methods: this was a retrospective study from January 1, 2013 to December 31, 2017 and included the records of patients aged 15 years and older surgically treated for a patella fracture in our center. Results: The work involved 36 patients including 28 men (77.8%) and 8 women (22.2%) with a mean age of 35.9 years. High way trauma were the first cause of these fractures. Fractures were open in 44.4% of cases. Type II according to Ricard and Moulay classification was the most represented with 58.3% of cases. The majority of the patients, 80.5%, were treated by rigging. Five (5) cases of hematoma, one (1) postoperative infection, and three (3) cases of knee stiffness complicated the short- and medium-term follow-up. With an average follow-up of 2 years 6 months, radiologically, normal consolidation was achieved in 86.1% of cases. Two (2) cases of delayed consolidation and three (3) cases of nonunion have been noted. Three (3) cases of patellofemoral osteoarthritis appeared at two years. From the functional point of view, according to the Bosman score, 27.8% were excellent, 63.9% were good, 8.3% were bad, and the cable rigging seemed to give excellent and good results. Conclusion: the treatment of transverse fractures of the patella must be exclusively surgical. Guying is an osteosynthesis technique of choice. Nevertheless complications including knee stiffness, non-union and patellofemoral osteoarthritis are not uncommo

Les dechets miniers phosphates, source de la pollution marine au Togo

No Abstract

L'impact de l'exploitation des phosphates sédimentaires et de Hahotoé-Kpogamé sur la pollution chimique des sédiments du fleuve Haho et du lac

No Abstract Available J. Rech. Sci. Univ. Lomé (Togo) 2002, 6(2) : 95-10

Distribution, speciation, and extractability of cadmium in the sedimentary phosphorite of Hahotoé-Kpogamé (Southern Togo)

The geochemistry and extractability of Cd in the phosphorite deposits of Hahotoé-Kpogamé (southern Togo) have been studied using various methodologies such as Cd distribution in profiles, grain-size dependence analysis of Cd content, Cd localization using scanning electron microscopy (SEM), sequential acid extraction, and a leaching experiment with artificial seawater. Results demonstrate that in the phosphorite deposits of Hahotoe-Kpogame, Cd is enriched by a factor of 157 compared to shale and by a factor of 3 compared to average world phosphorite composition. The main carrier of Cd appears to be apatite. This is evidenced by significant high positive correlations between the Cd content and P2O5 (in bulk sedimentr = 0.7 and in the 1–0.2 mm fraction r = 0.9). The grain-size dependence of Cd contents (concentrations decreasing with decreasing grain size) and SEM analysis supports these conclusions. Secondary Cd carriers include calcite, goethite, and various bone fragments. Sequential extraction tests with acetic acid and EDTA show an extraction rate reaching up to 40%. Leaching experiments with artificial seawater show evidence of Cd release in seawater. This leads to the conclusion that the processing of phosphorite by wet sieving using seawater and dumping of phosphorite tailings into the coastal waters of Togo can be a major source of marine pollution with Cd

Distribution, biodisponibilite et bioaccumulation des metaux lourds dans le systeme lagunaire de Lome

The sediments and some fishes species of the lagoon system of Lome have benn analyzed for their contents in heavy metals V, Cr, Ni, Cu, Zn, Sr, Pb, Cd, Fe, Al, Ti, Mn and As. The results show that the lagoon is very polluted by certain heavy metals such as cadmium, lead, zinc, chromium and nickel. This pollution is moderate in the case of copper, iron, aluminum and manganese. The analyzed elements show a south-north increasing distribution gradient that confirms the anthropogenic input of pollutants through the gutters entering directly into the lagoons. Domestic effluents, atmospheric pollution, the wild run off and cities dumps are the principal sources of pollution for the lagoons. The tests of extraction of metals using weak nitric acid (45 %) indicate that the high amounts of analyzed metals are bioavailable and have a man made origin. This high bioavailability is the main factor enhancing the high level of bioaccumulation of cadmium, lead and arsenic in tissues of fish species that are by ignorance fished and eaten by neighboring peopl

Increased bioavailability of mercury in the lagoons of Lomé, Togo: the possible role of dredging

Surface sediments of the lagoons of Lomé, Togo, were analyzed for mercury, methylmercury, and trace elements. Concentrations were greater than typical for natural lagoon sediments, and with greater variability within the Eastern lagoon compared to the Western one. The Eastern lagoon is larger and has been dredged in the past, while the Western lagoon, which also receives major waste inputs, has not been dredged and shows less tidal flushing. Accordingly, one naturally believes that the Eastern lagoon is cleaner and probably safe to use due to its natural resources, including fishes to eat. Unexpectedly, we describe here that mercury methylation was greater in the Eastern lagoon, indicating increased bioavailability of mercury, as probably facilitated by past dredging that decreased solidphase retention of inorganic mercury. Urbanization has historically been more developed in the southern part of the lagoons, which is still reflected in contamination levels of sediment despite dredging, probably because sources of contamination are still more important there today. Such urban contamination emphasizes the need to regulate waste discharges and possible airborne contamination in growing cities of developing countries, and implements environmental and public health monitoring, especially in relation to misbelieves systematically associated with the cleansing effect of dredging activity