Evaluating the toxicity of marine sediments from East Coast of Africa (Eritrea, Kenya and Tanzania) using algae Artemia bioassays and preliminary study of energy stores as alternative method to evaluate sediment toxicity
Hagos, K. (2007). Evaluating the toxicity of marine sediments from East Coast of Africa (Eritrea, Kenya and Tanzania) using algae Artemia bioassays and preliminary study of energy stores as alternative method to evaluate sediment toxicity. MSc Thesis. Universiteit Antwerpen/Vrije Universiteit Brussel (ECOMAMA): Brussel. 71 + app. pp. |
Available in | Author | | Document type: Dissertation
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Keywords | Chemical elements > Metals > Heavy metals Energy balance Marine sedimentation Properties > Biological properties > Toxicity Tests > Bioassays Artemia Leach, 1819 [WoRMS] Africa, Kenya [Marine Regions]; ISW, Africa, East [Marine Regions]; ISW, Kenya, Gazi Bay [Marine Regions] Marine/Coastal | Author keywords | ECOMAMA, Kenya Belgium project |
Abstract | Sediment toxicity assays constitute an important aspect of Environmental Risk Assessment (ERA) of persistent chemicals such as heavy metals. Marine sediments function as a sink for most persistent toxicants posing a potential risk to aquatic biota once resuspended into the water column. Therefore, the main objective of this study was to determine the toxicity of potential toxicity of sediments from the East Coast of Africa. In addition the study included samples from around the world in order to provide international perspective. The study showed that toxicity was low despite occasionally high levels of some metals. This was attributed to the hypothesis that the source of metals in East Africa was of natural origin and therefore sediments from this region were less bioavailable and toxic to the biota. Since the study also demonstrated that artemia was not so sensitive to detect low levels of toxicity at acute toxicity level, therefore the use of hatching bioassays and the changes in energy stores of mussels appeared to be more sensitive. In terms of inter-country comparisons, the study showed the highest metal concentrations in the Eritrean locations and least in remote locations of Kenya. |
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