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Hammam Sousse, Tunisia

Nouira T.,Higher Institute of Agriculture | Risso C.,CNRS Ecology of Marine Ecosystems and Responses to Stress Laboratory | Chouba L.,National Institute of science and Technologies of the Sea | Budzinski H.,University of Bordeaux 1 | Boussetta H.,Higher Institute of Agriculture
Chemosphere | Year: 2013

An assessment of PCB and PBDE contamination of surface sediments in Monastir Bay was carried out in two contrasted seasons of the year. Samples were collected from 5 sites and analyzed for the ∑7 marker PCBs (i.e. PCBs 28, 52, 101, 118, 138, 153 and 180) and ∑4 PBDE congeners (PBDEs 47, 99, 119 and 153) by GC/ECD. Concentrations of both PCBs and PBDEs showed seasonal variations. PCB concentrations were in the range of 3.1-9.3ngg-1 and 1.1-8.1ngg-1 in wet and dry season respectively, and sediments were considered moderately contaminated with PCBs. All PCBs analyzed were detected in surface sediments. PCB 153 and 52 congeners showed the highest relative abundance in both winter and summer. PBDE concentrations ranged from not detect to 0.1ngg-1, with only BDE-47 congener detected in sediments and only in winter. Analysis of spatial and seasonal variations indicated that PCB distribution is governed by hydrodynamics and temporal variability of inputs. While the PCB contamination appeared to be mainly land-based, PBDEs are suspected to originate from atmospheric deposition. © 2013 Elsevier Ltd.

Jebali J.,Higher Institute of Agriculture | Chicano-Galvez E.,University of Cordoba, Spain | Fernandez-Cisnal R.,University of Cordoba, Spain | Banni M.,Higher Institute of Agriculture | And 4 more authors.
Ecotoxicology and Environmental Safety | Year: 2014

This study uses proteomics approach to assess the toxic effects of contaminants in the Mediterranean crab (Carcinus maenas) after transplantation into Téboulba fishing harbour. High levels of aliphatic and aromatic hydrocarbons were detected in sediments. Although their effects on vertebrates are well described, little is known about their early biological effects in marine invertebrates under realistic conditions. Protein expression profiles of crabs caged for 15, 30 and 60 days were compared to unexposed animals. Nineteen proteins with significant expression differences were identified by capLC-μESI-IT MS/MS and homology search on databases. Differentially expressed proteins were assigned to five different categories of biological function including: (1) chitin catabolism, (2) proteolysis, (3) exoskeleton biosynthesis, (4) protein folding and stress response, and (5) transport. The proteins showing major expression changes in C. maenas after different caging times may be considered as novel molecular biomarkers for effectively biomonitoring aquatic environment contamination. © 2013 Elsevier Inc.

Jebali J.,Higher Institute of Agriculture | Chouba L.,Institute of Chemical Technology | Banni M.,Higher Institute of Agriculture | Boussetta H.,Higher Institute of Agriculture
Journal of Trace Elements in Medicine and Biology | Year: 2014

The purpose of this study was to investigate the long-term bioaccumulation and elimination of Cd, Pb, Mn, Zn and Fe by Pinna nobilis tissues after their 90 day-transplantation period at Téboulba fishing harbor. During the transplantation period, the Cd, Pb, Mn, Zn and Fe concentrations in the different tissues of the mussels were measured before and after exposure period. Metal (Cd, Pb, Mn, Zn and Fe) accumulation in P. nobilis mussels varied depending on the analyzed tissue and the caging times. Notable differences in Cd, Pb, Mn, Zn and Fe accumulation patterns within the digestive gland, gills and muscle were found and may be due to the ability of each tissue to accumulate metals. During the depuration phase, the elimination of Cd, Pb, Mn, Zn and Fe depended on the target tissue and the metal speciation. Cd, Pb, Mn and Fe were eliminated rapidly from one organ and increased in other when compared to those of 90 day transplanted mussels. The increase of metal loads during the elimination phase is not clear and particularly what kind of processes is responsible for such response. However, it is reasonable to assume that metals increase is related to the existence of an accumulation/detoxification mechanism, which involves the transport of metals from an organ to another. The data obtained indicate that because of the significantly high quantities of Cd, Pb, Mn, Zn and Fe accumulated during the exposure phase, the transplanted mussels are suitable bioindicators for monitoring trace metals in marine ecosystem. © 2013 Elsevier GmbH.

Jebali J.,Higher Institute of Agriculture | Chicano-Galvez E.,University of Cordoba, Spain | Banni M.,Higher Institute of Agriculture | Guerbej H.,National Institute of Marine science and Technology | And 3 more authors.
Ecotoxicology and Environmental Safety | Year: 2013

Gilthead seabream (Sparus aurata) specimens were caged in-field at the Téboulba harbour or exposed to benzo(a)pyrene [B(a)P] or to paraquat [PQ] plus B(a)P, and several biochemical biomarker responses were investigated. Antioxidant enzymes, such as glutathione peroxidase, catalase and glutathione reductase, significantly increased in the in-field and B(a)P+PQ exposures, but were only moderately affected by B(a)P alone. Glucose-6-phosphate and 6-phosphogluconate dehydrogenases significantly diminished after in-field exposure. Different responses with biotransformation enzymes were observed: the P4501A-associated EROD activity was highly induced in response to B(a)P and B(a)P+PQ exposures, while total activity of the glutathione S-transferase (GST) was similar to control. However, after purification of the GST proteins by affinity chromatograpy and analysis by two-dimensional electrophoresis, nineteen highly reproducible isoforms were resolved. In addition, some of reproducible isoforms showed different and specific expression patterns in response to contaminants.Thus, proteomic analysis of the purified GST subunits is a reliable tool for ecotoxicological research, useful in polluted marine ecosystem as an effective biomarker of contamination. © 2012 Elsevier Inc.

Kamel N.,Higher Institute of Agriculture | Jebali J.,Higher Institute of Agriculture | Banni M.,Higher Institute of Agriculture | Ben Khedher S.,Higher Institute of Agriculture | And 2 more authors.
Ecotoxicology and Environmental Safety | Year: 2012

This study assessed the responses of biochemical biomarkers and metals levels in . Ruditapes decussatus exposed to the increasing concentrations of treated municipal effluents (TME) discharged into the Tunisian coastal area. Clams were exposed to 0%, 1%, 3% and 10% for 7 and 14 day and the following biochemical responses were measured: (1) catalase activity and lipid peroxidation levels (TBARS) as oxidative stress biomarkers, (2) gluthathione S-transferase (GST) activity as a phase II conjugation enzyme; (3) cholinesterase activity (ChE) as biomarker of neurotoxicity, and (4) metallothioneins as a proteins highly induced by heavy metals. A significant uptake of Cu, Cd and Zn in digestive gland and serious biochemical alterations were observed. Thus, exposure of clams to croissant concentration of TME have the potential to increase the oxidative stress biomarkers (TBARS, CAT activity) and MT levels; and decrease ChE activity in both gills and digestive gland. Current experimental results suggest that CAT, GST, ChE activities and MT and TBARs levels in gills and digestive gland of clam . R. decussatus are sensitive and suitable responses for assessing the effects of anthropogenic contaminants on the aquatic ecosystems, particularly effluent complex mixtures. © 2012 Elsevier Inc.

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