Distribution pattern of persistent organic pollutants in aquatic ecosystem at the Rosetta Nile branch estuary into the Mediterranean Sea, North of Delta, Egypt.

The objective of this study was to evaluate the distribution pattern of persistent organic pollutants in water, sediment and aquatic biota represented by Oreochromis niloticus and Donax trunculus at the Rosetta Nile branch estuary. α-HCH, p,p'-DDE and polychlorinated biphenyls were the predominant compounds detected at ranges of 0.54-4.90 ng/l water, 0.75-2.41 ng/g, d. wt. sediment and 2.19-28.11 ng/g, fresh wt. biota. β and γ-HCHs, endosulfan compounds, heptachlor and heptachlor epoxide were at low detection frequencies. Totally, the organochlorine pollutants were at high levels and abundances in Donax spp. than in Tilapia spp. followed by sediment and water. These levels were ranged between lower and higher than those found by the other studies established in Egypt, and well below its tolerable residue levels in fish. A correlation was found for the quantified pollutants between water, sediment and biota. This is clearly reflecting the bioaccumulation properties of these compounds.