Department Of Marine Sciences

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https://ir.unilag.edu.ng/handle/123456789/3388
From its inception in 1962, the University of Lagos has been identified as a potential centre for the development of Marine Biology and Fisheries in Nigeria. At that time, it was the only University/ Institution in Nigeria situated by the sea and it was obvious that it was most suitable for the development of such disciplines. In the absence of a Faculty of Agriculture and taking full benefit of its location by the sea, lagoon and river, the University of Lagos is one of the very rare institutions in the world suitable for the establishment of a Marine Biology and Fisheries programme.

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Browsing Department Of Marine Sciences by Subject "API gravity"

Now showing 1 - 3 of 3
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    Open Access
    Acute toxicity of some nigerian crude oils on black jaw tilapia (Sarotherodon melanotheron) Juveniles
    (Fisheries Society of Nigeria, 2018) Omogoriola, H.O; Ayoola, S. O.
    Oil industry activities are sources of major contamination problems in Niger Delta. Pollutants from these activities have significant deleterious effects on aquatic organisms. The study investigated the LC50 values obtained from acute toxicity tests on Sarotherodon melanotheron using Oil- in-Water Dispersion (OWD) of the three selected Nigerian crude oils –Ebok, Meji and Erha. The acute toxicity concentrations of 0, 2, 4, 6 and 8ml/L, 0, 10, 15, 20, and 25ml/L and 0, 25, 37.5, 50 and 62.5ml/L were used to determine the 96h Lethal Concentration (LC50) of Ebok (heavy), Meji (light) and Erha (medium) crude oils respectively. The analysis of variance (ANOVA) showed that there were significant differences (p<0.05) in the quantal response of S. melanotheron to different concentrations of three crude oils at different hours of exposure. These results showed that 96LC50 values for OWD-Ebok, OWD-Meji and OWD-Erha crude oils on S. melanotheron were 0.56ml/L, 6.78ml/L and 24.82ml/L respectively. Based on the acute toxicity tests, Ebok with lower API (>22.30C) gravity was more toxic than other crudes on S. melanotheron. All crude oils were toxic to the fish; their discharge into the water bodies during crudes exploration and exploitation should be discouraged for a safety environment.
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    Open Access
    Acute Toxicity of Water Accommodated Fractions (WAFs) of three Nigerian Crude Oils to Clarias gariepinus (Burchell, 1822)
    (Department of Aquaculture and Fisheries Management, University of Ibadan, 2017) Omogoriola, H.O; Ayoola, S. O.
    Oil industry activities such as exploration, transportation, storage, use and disposal, as well as oil spills are sources of major contamination problems in Niger Delta, which have significant deleterious effects on aquatic organisms. The objective of this study was to report LC values 50 obtained from acute toxicity tests on the African Catfish, C. gariepinus exposed to Water Accommodated Fraction (WAF) –heavy (Ebok), light (Meji) and medium (Erha) crude oils. Acute toxicity concentrations of 0%, 2%, 4%, 6% and 8%, 0%, 15%, 20%, 25% and 30% and c 0%, 40%, 60%, 80% and 100% were used to determine the 96h Lethal Concentration (LC ) of 50 heavy, light and medium crude oils respectively. The analysis of variance (ANOVA) showed that there was a significant (p<0.05) difference in the quantal response of C. gariepinus to different concentrations of the various crude oil types at 24, 48, 72 and 96 hours exposure. These results showed that 96LC values for heavy, light and medium crude oils on C. 50 gariepinus were 0.028 mg TPH/l, 0.177 mg TPH/l and 0.742 mg TPH/l respectively. The 96LC of WAF showed that the heavy crude oil was six times more toxic than light and twenty 50 six times more toxic than medium and on toxicity categorization, the heavy, light and medium crude oils were very highly toxic, highly toxic and highly toxic on C. gariepinus. Based on the acute toxicity tests, heavy with lower API (<22.30C) gravity was more toxic than other crude oils on C. gariepinus. All crude oils are toxic to aquatic organisms especially the fish; their discharge into the water bodies during crude oil exploration, transportation, storage and even sabotage should be discouraged to protect the environment.
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    Open Access
    Comparative study of acute toxicity of three Nigerian crude oils using oil in water dispersion (OWD) method on Clarias gariepinus (African catfish)
    (University of Lagos, 2018) Omogoriola, H.O; Ayoola, S. O.; Otitoloju, A.A
    Oil industry activities such as exploration, transportation, storage, use and disposal, as well as oil spills are sources of major contamination problems in Niger Delta, which have significant deleterious effects on aquatic organisms. The study was to investigate LC50 values obtained from acute toxicity tests on C.gariepinus using Oil in Water Dispersion (OWD) of Ebok,Meji and Erha. The acute toxicity concentrations of Ebok(0, 4, 6, 8 and 10ml/l), Meji (0, 15, 20, 25, and 30 ml/l) andErha (37.5, 50, 62.5 and 75ml/l)were used to determine the 96h Lethal Concentration (LC50) respectively. The analysis of variance (ANOVA) showed that there was a significant difference (p<0.05) in the quantal response of C.gariepinus to different concentrations of Ebok, Meji and Erha crude oils at 24, 48, 72 and 96hours of exposure. These results showed that 96LC50 values for Ebok, Meji and Erha crude oils on C.gariepinus were 6.35 ml/l, 18.35 ml/l and 32.04ml respectively. These showed that Ebok was three times more toxic than Meji and five times more toxic than Erha while Meji crude oil was two times more toxic than Erha on C.gariepinus. Based on the acute toxicity tests, Ebok with lower API gravity is more toxic than other crude oils in C.gariepinus. All crude oils are toxic to aquatic organisms especially the fish; their discharge into the water bodies during crude oil exploration, transportation and storage should be discouraged for a safety environment.