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(M/EH088) Impact of land-based sources of pollution on Abu Kir Bay, Egypt. SAAD, Massoud1, Younis, Walid1, 1 ABSTRACT- Untreated industrial and sewage wastes from various land-based sources and contaminated agricultural run-off are discharged extensively into Abu Kir bay, a semi-enclosed heavily polluted basin located east of Alexandria, Egypt. The exchange of water between this bay and Lake Edku, lying at its southeastern region, occurs via a narrow channel. This study, a part of a research project, deals with the dissolved and particulate fractions of heavy metals in this bay and in the effluents of land-based sources discharging into it. The paper, textile, dyes and weaving industries are considered as main contributors of both metal fractions into the bay. The discharged metal fractions might be subjected in the receiving drainage waters to some alterations; dilution, absorption by vegetation and adsorption onto suspended matter (SM) and sediments. Also, the levels of both metal fractions in the effluents varied markedly from those in the wastewater discharged into the bay. In all samples, the particulate fractions of Fe, Pb and Hg dominated the dissolved fractions. However, the dissolved Mn was much more abundant than particulate Mn and dissolved Cd was the main constituent of total Cd. The high concentrations of particulate metal fractions were associated with high organic load and SM, derived mainly from untreated industrial wastes, showing significant positive correlation with SM and with each others. This suggests that all particulate metals were derived from the same source. Generally, all metal fractions showed remarkable increase in the surface and bottom waters in the inshore locations, directly affected by wastewater discharges and exhibited a decrease towards the offshore stations. The levels of metal fractions showed marked variations in the surface and bottom waters. These resulted mainly from different processes, such as remobilization, regeneration from SM and sediments, phenomena occurring in the freshwater - seawater interface, biological activities and dispersion behavior. Key words: Metal, pollution, Mediterranean, Egypt |
