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Ecotoxicological studies on marine ecosystem along the North Eastern Mediterranean Sea Coast of Libya /

Mariam Ambarak Saied Busaadia

Ecotoxicological studies on marine ecosystem along the North Eastern Mediterranean Sea Coast of Libya / دراسات بيئية سمية علي النظام البيئي البحري بساحل البحر المتوسط شمال شرق ليبيا Mariam Ambarak Saied Busaadia ; Supervised Mohamed Assem Said Marie , Wael Abdelmoneim Omar - Cairo : Mariam Ambarak Saied Busaadia , 2018 - 150 P. : charts , facsimiles ; 25cm

Thesis (Ph.D.) - Cairo University - Faculty of Science - Department of Zoology

The marine environment of the Mediterranean Sea coast of Libya is subjected to increasing anthropogenic activities. The present study assesses the impacts of some toxic metals in their complex state on common marine fish species; Mugil cephalus collected from four sites along the north eastern Mediterranean Sea coast of Libya. Metal concentrations (Cu, Zn, Mn, Cd, Pb, Fe and Al) in water, sediments and selected fish tissues were detected. Moreover, fish body condition indices, metal bioaccumulation factor (BAF) and metal pollution index (MPI) were calculated. Comparable data are presented concerning the oxidative stress biomarkers, DNA fragmentation and RAPD-PCR analysis in fish muscle and gills as well as histopathological changes in gills, liver and kidney samples as general biomarkers of the pollution condition. The level of sediment contamination expressed as sediment contamination factor (SCF), sediment pollution load index (SPLI), enrichment factor (EF) and geoaccumulation index (Igeo) was discussed. Generally, the results showed that site 1 (Benghazi City) followed by site 3 (Tobrok City) were the most contaminated areas in comparison to both site 2 (Sousa City) and site 4 (Elburdi City - the reference site). Metal concentrations in fish tissues showed tissue-specific accumulation pattern. MPI values gave a better view of metal accumulation in the studied tissues as: kidney > liver > gills > skin > muscle. It also showed the metal concentrations along the studied sites as: site 1 > site 3 > site 2 > site 4. The highest percentage of DNA fragmentation was recorded significantly in site 1 followed by site 3. RAPD-PCR analysis showed high similarity among fish collected from sites 2 and 3, medium similarity among fish collected from both sites 2 and 3 in relation to site 4 and low similarity between fish of site 1 in relation to other sites. Histopathological alterations and evident damages were observed in tissues of fish collected from the polluted sites



Biomarkers Marine pollution Metal toxicity