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Qualitative Determination of Photodegradation Products of Progesterone and Testosterone in Aqueous Solution

American Journal of Analytical Chemistry 2016年第1期7卷 22-33页

作者： Ladji Méité Baba Donafologo Soro Narcisse Kouassi Aboua Véronique Mambo karim sory traoré Patrick Mazellier Joseh De Laat Laboratoire des Sciences de l’Environnement Unité de Formation et de Recherche des Sciences et Gestion de l’Environnement Université Nangui Abrogoua Abidjan Cote d’Ivoire CNRS-UMR 5805 EPOC Laboratoire de Physico et Toxico Chimie de l’Environnement Université de Bordeaux Bordeaux France Institut de Chimie des Milieux et Matériaux de Poitiers (UMR CNRS 7285) Equipe Eaux Géochimie Santé Ecole Nationale Supérieure d’Ingénieurs de Poitiers Université de Poitiers Poitiers France

Direct photochemical degradations of progesterone (PR) and testosterone (TR), two naturally produced hormones, have been conducted in non-buffered aqueous solution (pH ranging between 5.5 and 6.0). The irradiation experiments were carried out in a batch reactor upon monochromatic (254 nm) and polychromatic (λ > 290 nm) at 25°C. GLC/MS and LC/UV-DAD/MS analyses were performed to investigate phototransformation products after a solid phase extraction (SPE) step for analytes concentration. For each compound several by-products have been identified and are the same ones under both irradiation conditions. Because of the presence of the same chromophore (α, β-unsaturated group) absorbing UV radiations in both hormones, the majority of chromatographic peaks correspond to by-products formed according to identical mechanisms involving isomerization, enolization, oxidation and hydration to lead to the generation of lumiketone, cyclopentenone, spiro-hydration, oxidation and hydroxylation photoproducts.

关键词： Photoproducts Testosterone Progesterone GLC/MS LC/UV-DAD/MS

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Level of Contamination of Fishponds Water in Pesticide Residues and Metallic Trace Elements (Pb, Cd, As, Hg): Case of Fishponds of ZEPREGUHE (Daloa, Côte d’Ivoire)

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Journal of Agricultural Chemistry and Environment 2022年第4期11卷 307-317页

作者： Kacou Alain Paterne Dalogo Ano Guy Serge Ehouman James Halbin Kouadio David Leonce Kouadio Edi Jean Frejus Ehui karim sory traore Laboratory of Environmental Sciences and Technology Jean Lorougnon GUEDE University Daloa C&ocirc te d’Ivoire Laboratory of Environmental Sciences Nangui Abrogoua University Abidjan C&ocirc te d’Ivoire Agroforestry Training and Research Unit Biochemistry-microbiology Department Agrovalorisation Laboratory Jean Lorougnon GUEDE University Daloa C&ocirc te d’Ivoire

Fishponds waters intended to satisfy the nutritional needs of the populations in terms of supply of fish resources are strongly and unfortunately exposed to the mobility and dispersion of metallic trace elements (TMEs) or to the persistence in the environment and in the form of pesticide residues from human activities. The objective of this work is to evaluate, on the one hand, the levels of identified pesticide residues and, on the other hand, those of researched TMEs (lead, cadmium, mercury and arsenic) in the waters of ponds used for fish farming in Zépréguhé, a locality located 9 km from the town of Daloa in the centre-west of Côte d’Ivoire. The dosage of the samples carried out by means of a gas chromatograph coupled to a mass spectrometer (GC/MS) made it possible to detect nine (9) pesticide molecules, including eight (8) organochlorines and a single molecule from the pyrethroid family, obtained from the detection limit of 0.006 μg/L and the quantification limit of 0.018 μg/L. The maximum average concentration was obtained with α-endosulfan for a content reaching 0.8038 μg/L and well above the maximum admissible concentration of 0.1 μg/L. The TMEs were quantified using an atomic absorption spectrophotometer (AAS). Arsenic is the most abundant metal with an average concentration of 9.497 μg/L. With the exception of lead, these measured levels are above the acceptable limit values for freshwater. This study showed that human activities such as the use of fertilisers and plant protection products in plantations, sand extraction and road traffic have a negative impact on the quality of the water in ponds used for fish breeding.

关键词： Fishpond Water Metallic Trace Elements Pesticide Residues Maximum Residue Levels

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Desorption of Methylene Blue Adsorbed on Activated Carbon from Cocoa Pod Shell

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Open Journal of Applied Sciences 2023年第5期13卷 605-617页

作者： David Léonce Kouadio Yapo Aristide Hermann Yapi Djedjess Essoh Jules César Meledje Kacou Alain Paterne Dalogo Djamatché Paul Valery Akesse Brou Dibi karim sory traore Laboratoire des Sciences et Technologie de l’Environnementale Université Jean Lorougnon Guede C&#244te d’Ivoire Laboratoire des Sciences Physiques Fondamentales et appliquées école Normale Supérieure (Abidjan) Abidjan C&#244te d’Ivoire Laboratoire des Sciences de l’Environnement Université Nangui Abrogoua C&#244te d’Ivoire

Environmental protection has become a concern for the world. For this reason, the objective of this work is to remove methylene blue adsorbed on activated carbon. The coal used comes from cocoa pod shells. Before pyrolysis, the shells were ground, sieved and impregnated with orthophosphoric acid. Before desorption, the activated carbons were initially saturated with MB. These saturated coals were brought into contact with a sodium chloride (NaCl) solution and then stirred. The evolution of the resorbed MB concentration was monitored by spectrophotometry. The desorption tests showed a remarkable elimination from the first 10 minutes. The desorption kinetics comprises two phases: a rapid kinetics between 0 and 30 minutes and a slow kinetics between 30 and 60 minutes. The desorption of the dye reaches a concentration aqual to 0.84 mg/l at pH = 4 at temperature = 80°C. For modeling, the coefficient of the Langmuir II model is greater than or equal to O.9893. The model of Langmuir III is less than or equal to 0.9373. The Freundlich model coefficient is 0.9842 or less. The desorption is thefore carried out on energy-homogeneous adsorption sites and without any interaction between the adsorbed cations of the dye. Experimental parameters such as pH, temperature and concentration of sodium chloride (NaCl) solution influence the desorption of MB. And the model of Langmuir II describes well the process of desorption of the MB.

关键词： Desorption Activated Carbon Methylene Blue Isotherm Sodium Chloride

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