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Assessment of trace element contamination and bioaccumulation in algae (Ulva lactuca), mussels (Perna perna), shrimp (Penaeus kerathurus), and fish (Mugil cephalus, Saratherondon melanotheron) along the Senegalese coast
2016
Diop, Mamadou | Howsam, Michael | Diop, Cheikh | Goossens, Jean | Diouf, Amadou | Amara, Rachid | Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 (LOG) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Nord]) | Université Cheikh Anta Diop de Dakar [Sénégal] (UCAD) | Université du Littoral Côte d'Opale (ULCO) | Facteurs de Risque et Déterminants Moléculaires des Maladies liées au Vieillissement - U 1167 (RID-AGE) ; Institut Pasteur de Lille ; Pasteur Network (Réseau International des Instituts Pasteur)-Pasteur Network (Réseau International des Instituts Pasteur)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Lille-Centre Hospitalier Régional Universitaire [CHU Lille] (CHRU Lille) | Lille Inflammation Research International Center - U 995 (LIRIC) ; Institut Pasteur de Lille ; Pasteur Network (Réseau International des Instituts Pasteur)-Pasteur Network (Réseau International des Instituts Pasteur)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Lille-Centre Hospitalier Régional Universitaire [CHU Lille] (CHRU Lille) | Centre Universitaire de Mesures et d'Analyses [Université de Lille] (CUMA) ; Université de Lille, Droit et Santé | Centre d'Etudes et de recherche en Santé-Travail-Environnement (CERESTE) | CSIC-Barcelone | Faculteit der Aard- en Levenswetenschappen, Vrije Universiteit ; Vrije Universiteit Amsterdam [Amsterdam] (VU) | INSTITUTE OF ENVIRONMENTAL AND BIOLOGICAL SCIENCES LANCASTER GBR ; Partenaires IRSTEA ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)
International audience | Concentrations of 11 elements were quantified in five marine species from different trophic levels of a food web (algae, mussel, shrimp and fish), representative for shallow Senegalese coastal waters, and including species of commercial importance. Significant differences in element concentrations and bioaccumulation were demonstrated, revealing the utility of employing a suite of organisms as bioindicators to monitor metal contamination in coastal areas. There was no clear seasonal pattern in concentration of elements, however inter-site differences were observed. Calculations of transfer factors for all the studied elements showed that transfer factors from water were greater than those from sediments. For shrimp and mussel, the concentrations of Pb and Cd were below the EU's maximum level for human consumption, however high concentrations of arsenic in shrimp were recorded at all sites.
Show more [+] Less [-]Assessment of trace element contamination and bioaccumulation in algae (Ulva lactuca), mussels (Perna perna), shrimp (Penaeus kerathurus), and fish (Mugil cephalus, Saratherondon melanotheron) along the Senegalese coast
2016
Diop, Mamadou | Howsam, Michael | Diop, Cheikh | Goossens, Jean | Diouf, Amadou | Amara, Rachid | Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 (LOG) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Nord]) | Laboratoire de Toxicologie et Hydrologie ; Université Cheikh Anta Diop de Dakar [Sénégal] (UCAD) | Université du Littoral Côte d'Opale (ULCO) | Facteurs de Risque et Déterminants Moléculaires des Maladies liées au Vieillissement - U 1167 (RID-AGE) ; Institut Pasteur de Lille ; Réseau International des Instituts Pasteur (RIIP)-Réseau International des Instituts Pasteur (RIIP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Lille-Centre Hospitalier Régional Universitaire [Lille] (CHRU Lille) | Lille Inflammation Research International Center - U 995 (LIRIC) ; Institut Pasteur de Lille ; Réseau International des Instituts Pasteur (RIIP)-Réseau International des Instituts Pasteur (RIIP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Lille-Centre Hospitalier Régional Universitaire [Lille] (CHRU Lille) | Centre Universitaire de Mesures et d'Analyses [Université de Lille] (CUMA) ; Université de Lille, Droit et Santé | Centre d'Etudes et de recherche en Santé-Travail-Environnement (CERESTE) | CSIC-Barcelone | Faculteit der Aard- en Levenswetenschappen, Vrije Universiteit ; Vrije Universiteit Amsterdam [Amsterdam] (VU) | INSTITUTE OF ENVIRONMENTAL AND BIOLOGICAL SCIENCES LANCASTER GBR ; Partenaires IRSTEA ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)
International audience | Concentrations of 11 elements were quantified in five marine species from different trophic levels of a food web (algae, mussel, shrimp and fish), representative for shallow Senegalese coastal waters, and including species of commercial importance. Significant differences in element concentrations and bioaccumulation were demonstrated, revealing the utility of employing a suite of organisms as bioindicators to monitor metal contamination in coastal areas. There was no clear seasonal pattern in concentration of elements, however inter-site differences were observed. Calculations of transfer factors for all the studied elements showed that transfer factors from water were greater than those from sediments. For shrimp and mussel, the concentrations of Pb and Cd were below the EU's maximum level for human consumption, however high concentrations of arsenic in shrimp were recorded at all sites.
Show more [+] Less [-]Individual exposure level following indoor and outdoor air pollution exposure in Dakar (Senegal)
2019
The consequences of indoor and outdoor air pollution on human health are of great concern nowadays. In this study, we firstly evaluated indoor and outdoor air pollution levels (CO, CO₂, NO, NO₂, PM₁₀) at an urban site in Dakar city center and at a rural site. Then, the individual exposure levels to selected pollutants and the variations in the levels of biomarkers of exposure were investigated in different groups of persons (bus drivers, traders working along the main roads and housemaids). Benzene exposure levels were higher for housemaids than for bus drivers and traders. High indoor exposure to benzene is probably due to cooking habits (cooking with charcoal), local practices (burning of incense), the use of cleaning products or solvent products which are important emitters of this compound. These results are confirmed by the values of S-PMA, which were higher in housemaids group compared to the others. Urinary 1-HOP levels were significantly higher for urban site housemaids compared to semirural district ones.Moreover, urinary levels of DNA oxidative stress damage (8-OHdG) and inflammatory (interleukin-6 and -8) biomarkers were higher in urban subjects in comparison to rural ones.The air quality measurement campaign showed that the bus interior was more polluted with PM₁₀, CO, CO₂ and NO than the market and urban or rural households. However, the interior of households showed higher concentration of VOCs than outdoor sites confirming previous observations of higher indoor individual exposure level to specific classes of pollutants.
Show more [+] Less [-]Physico-chemical characterization and in vitro inflammatory and oxidative potency of atmospheric particles collected in Dakar city's (Senegal)
2019
(Maurizio),
Exposure to atmospheric pollutants has been recognized as a major risk factor of respiratory and cardiovascular diseases. Fine particles (PM2.5) and a coarser fraction (PM>2.5) sampled at an urban site in Dakar (HLM), characterized by high road traffic emissions, were compared with particles sampled at a rural area, Toubab Dialaw located about 40 km from Dakar. The physicochemical characteristics of samples revealed that PMs differ for their physical (surface area) and chemical properties (in terms of CHN, metals, ions, paraffins, VOCs and PAHs) that were 65–75% higher in urban samples. Moreover the fine PMs contain higher amounts of anthropogenic related pollutants than the PM>2.5 one. These differences are sustained by the ratios reported for the analysed PAHs which suggest as predominant primary emission sources vehicle exhausts at urban site and biomass combustion at the rural site. The inflammatory response and the oxidative damages were evaluated in BEAS-2B cells by the quantification of 4 selected inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-8) and of total carbonylated proteins and the oxidative DNA adduct 8-OHdG after 8 or 24 h exposure. In accordance with the different sources and different physical and chemical properties, the inflammatory response and the oxidative damages were found higher in bronchial cells exposed to urban PMs. These data confirm the importance, also for West African countries, to evaluate the correlation between PM physico-chemical properties and potential biological impacts.
Show more [+] Less [-]Assessment of contamination, distribution and chemical speciation of trace metals in water column in the Dakar coast and the Saint Louis estuary from Senegal, West Africa
2014
Diop, Cheikh | Dewaelé, Dorothée | Diop, Mamadou | Touré, Aminata | Cabral, Mathilde | Cazier, Fabrice | Fall, Mamadou | Diouf, Amadou | Ouddane, Baghdad
The water column from Dakar coast and Saint Louis estuary in Senegal, West Africa, was sampled in order to measure the contamination level by trace metals. The speciation of metals in water allowed performing a distribution between dissolved and particulate trace metals. For the dissolved metals, the metallic concentration and repartition between the organic fraction and the inorganic fraction were performed. The results show that the pollution of the estuary was more serious than in Dakar coast for Co, Cr, Ni, Pb and Zn; while, Cd and Cu were higher in Dakar coast. A strong affinity between metals and suspended particles has been revealed. Dissolved metals that have a tendency to form organic metal complexes are in decreasing order: Cd, Zn, Pb, Co=Cr=Mn, Cu and Ni. The results showed that the mobility of trace metals in estuary is controlled by dissolved organic carbon, while in coast it depends on chlorides.
Show more [+] Less [-]Hydrocarbon pollution in Atlantic coast of Mauritania (Levrier Bay Zone): Call for sustainable management
2021
Elmamy, Cherif Ahmed Ahmed | Abdellahi, Bah Mohamed Lemine | Er-Raioui, Hassan | Dartige, Aly | Zamel, Mohamed Lemine | Deida, Pr Mohamed Vadel
Levrier Bay is an important fishing area which is under growing anthropogenic pressures seriously threatening this treasure. Among these pressures Polycyclic Aromatic Hydrocarbon are of great environmental concern. Therefore, 16 EPA-PAHs were analyzed using GC–MS in Perna perna species and sediment. Comparison with Dakar (Senegal) and Moroccan coasts shows that PAHs levels are strikingly lower than that of heavily polluted Dakar coast (2474 μg/kg); nevertheless, comparable to Moroccan Casablanca and Tangier coasts (245 and 351 μg/kg, respectively). Ratio analysis indicates the predominance of pyrogenic sources and partial contribution of automotive traffic for the half of 4 sites. Furthermore, statistical analys shows that there are no significative differences, except for Benzo(b)Fluorentene in P. perna tissue and 4 PAHs (Fluorene; Fluorenthene; Pyrene; diBenzo(ah)Anthracene and dBahANT) in sediment for sites samples. Furthermore, bioconcentration indicates that P. perna is an excellent PAHs bioindicator. This points the necessity for immediate introduction of a sound Pollutants monitoring system.
Show more [+] Less [-]Effects of the sandbar breaching on hydrobiological parameters and zooplankton communities in the Senegal River Estuary (West Africa)
2014
Champalbert, Gisèle | Pagano, Marc | Arfi, Robert | Chevalier, Cristèle
This study describes the changes in hydrology, zooplankton communities and abundance in the Senegal River Estuary (SRE) before and after the breaching of the sandbar in October 2003. Samples were taken in 2003 at 3 stations located upstream (DI), in mid estuary (HY) and downstream (RM), and in 2005 at the same stations (RM becoming Old River Mouth: ORM), plus the new river mouth (NRM) resulting from the morphological evolution of the SRE.The study showed marked seasonal variations that affected the structure and distribution of zooplankton as well as major changes caused by the sandbar opening:–increased marine influence throughout the whole SRE,–changes in the horizontal gradients,–arrival of euryhaline species and increase in meroplankton, in particular decapod larvae,–transformation of the ORM area into a slackwater area with limited exchanges and the highest zooplankton numbers during high waters.
Show more [+] Less [-]Assessment of trace element contamination and bioaccumulation in algae (Ulva lactuca), mussels (Perna perna), shrimp (Penaeus kerathurus), and fish (Mugil cephalus, Saratherondon melanotheron) along the Senegalese coast
2016
Diop, Mamadou | Howsam, Michael | Diop, Cheikh | Goossens, Jean F. | Diouf, Amadou | Amara, Rachid
Concentrations of 11 elements were quantified in five marine species from different trophic levels of a food web (algae, mussel, shrimp and fish), representative for shallow Senegalese coastal waters, and including species of commercial importance. Significant differences in element concentrations and bioaccumulation were demonstrated, revealing the utility of employing a suite of organisms as bioindicators to monitor metal contamination in coastal areas. There was no clear seasonal pattern in concentration of elements, however inter-site differences were observed. Calculations of transfer factors for all the studied elements showed that transfer factors from water were greater than those from sediments. For shrimp and mussel, the concentrations of Pb and Cd were below the EU's maximum level for human consumption, however high concentrations of arsenic in shrimp were recorded at all sites.
Show more [+] Less [-]Removal of lead and cadmium from aqueous solutions by using 4-amino-3-hydroxynaphthalene sulfonic acid-doped polypyrrole films
2018
Sall, MohamedLamine | Diaw, AbdouKarim Diagne | Gningue-Sall, Diariatou | Chevillot-Biraud, Alexandre | Oturan, Nihal | Oturan, MehmetAli | Fourdrin, Chloé | Huguenot, David | Aaron, Jean-Jacques
Water pollution by heavy metals is a great health concern worldwide. Lead and cadmium are among the most toxic heavy metals because they are dangerous for the human and aquatic lives. In this work, the removal of lead and cadmium from aqueous solutions has been studied using electrosynthesized 4-amino-3-hydroxynaphthalene-1-sulfonic acid-doped polypyrrole (AHNSA-PPy) films as a new adsorbent. Two distinct methods, including the immersion method, based on the Pb²⁺ and Cd²⁺ spontaneous removal by impregnation of the polymer in the solution, and the electro-elimination method, consisting of removal of Pb²⁺ and Cd²⁺ ions from the solution by applying a small electrical current (5 mA) to the polymer film, were developed: the evolution of Pb²⁺ and Cd²⁺ concentrations with time was monitored by inductively coupled plasma optical emission spectrometry (ICP-OES). The effect of pH on the adsorption and electro-elimination of Pb²⁺ and Cd²⁺ using the AHNSA-PPy film was investigated and optimized, showing that the ionic adsorption and electro-elimination processes were highly pH-dependent. The kinetics of Pb²⁺ and Cd²⁺ adsorption and electro-elimination were found to follow second-order curves. The maximum adsorption capacity values of the AHNSA-PPy film were 64.0 and 50.4 mg/g, respectively, for Pb²⁺ and Cd²⁺. The removal efficiency values were, respectively, for Pb²⁺ and Cd²⁺, 80 and 63% by the immersion method, and 93 and 85% by the electro-elimination method. Application of both methods to Senegal natural waters, fortified with Pb²⁺ and Cd²⁺, led to removal efficiency values of, respectively for Pb²⁺ and Cd²⁺, 76–77 and 58–59% by the immersion method, and of 82–90 and 80–83%, by the electro-elimination method.
Show more [+] Less [-]Removal of Cr(VI) from aqueous solution using electrosynthesized 4-amino-3-hydroxynaphthalene-1-sulfonic acid doped polypyrrole as adsorbent
2017
Polypyrrole (PPy) conducting films, doped with 4-amino-3-hydroxynaphthalene sulfonic acid (AHNSA), were electrosynthesized by anodic oxidation of pyrrole on Pt and steel electrodes in aqueous medium (0.01 M AHNSA +0.007 M NaOH, using cyclic voltammetry (CV), and their electrochemical properties were studied. Fourier-transform infrared (FT-IR) spectroscopy confirmed the formation of AHNSA-PPy films. Their morphology was characterized by scanning electron microscopy (SEM), and their optical properties, including UV-VIS absorption and fluorescence spectra, were also investigated. AHNSA-PPy films were used for the removal of chromium(VI) from aqueous solution, by means of the immersion method and the Cr(VI) electro-reduction method. The effect of various experimental parameters, including the adsorbent (polymer) mass, pH, type of electrodes, and current intensity, on the adsorption of chromium by the polymer was performed and optimized. The adsorption and electro-reduction of (Cr VI) on the AHNSA-PPy film surface were found to be highly pH-dependent, and the kinetics of Cr(VI) adsorption and electro-reduction followed second-order kinetic curves. Apparent second-order rate constants were about three times higher for the Cr(VI) electro-reduction method than for the immersion method, indicating that the use of electro-reduction method significantly accelerated the chromium adsorption process on polymer. The maximum adsorption capacity of the AHNSA-PPy film for chromium was 224 mg g⁻¹. A 96% chromium removal from pure aqueous solution was reached within about 48 h by the immersion method, but only within about 6 h by the Cr(VI) electro-reduction method. Application of both methods to Cr(VI) fortified natural waters of Senegal led to chromium removal efficiency high values (93 to 96% according to the type of natural water).
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