الفهرس 
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Abstract
El-Mex district is an industrial zone lies to the west of Alexandria city along the Mediterranean coast of Egypt. El-Mex coastal water receives considerable amounts of untreated industrial, agricultural and domestic waters mainly through El-Umum drain.
This study were carried out to quantify the organochlorines and polychlorinated biphenyls residues in the bay sediments .
In November, 1995, twenty two bottom sediments samples were collected. The locations of samples were selected on a grid profile to cover the majority of different bottom sediments types, depths and taking into consideration the impact of the point source (El-Umum drain).
The sediments were laboratory analyzed for mean grain size and total organic carbon content in tandem with the analytical quantification of organochlorine compounds and polychlorinated biphenyls. The correlation coefficient was computed to reveal the relation between the measured variables.
The study area were divided into six sectors according to the sites of significant variability in depths, mean grain sizes (Mz), and total organic carbon contents (TOC%) according to Rifaat, 1982 and Rifaat et al., 1997.
The organochlorines (OCs) and polychlorinated biphenyls (PCBs) levels were quite low in the majority of sites. The highest level for OCs was 1607.94 ngg-1ww at station M18 of medium silt sediment, low depth of 3 m and high values of both Mz and TOC% (at site V, southern end of the bay). The lowest level was 0.03 ngg-1 ww. at station M20 of coarse silt sediment, depth of 50 m and low values of both Mz and TOC% (at site VI, remote area).
The total PCBs were ranged from 0.1 to 947.87 ngg-1ww at station M20 (at remote site) and station M17 (at site V) of fine silt sediment, high values of both Mz and TOC% and depth of 8.5 m; respectively.
Those higher concentrations of OCs and PCBs were accumulated in the area of poor flushing rate at site V in medium and fine silt sediments, characterized by higher values of both Mz and TOC%, This high accumulation was also supported by the surface current directions south-southwest loaded with contaminated suspended particles from El-Umum outfall. All these factors react together to favor the accumulation in site V, resulting in its consideration as a cumulative area over the past years.