LEVEL OF CHLORINATED HYDROCARBONS IN A TELEOST FISH AND A BIVALVE FROM THE EGYPTIAN MEDITERRANEAN COAST AND NILE ESTUARY

The residues of 22 organochlorine pollutants in fish Mugil cephalus an d a bivalve Donax sp. collected from three different locations, i.e. A bu-Quir bay, Demiatta and Gamasa, were analysed by capillary GLC. The pollutants studied were 1,1,1,-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) isomers, cyclodiene compounds, ooctahydro-1.3.4-metheno-2H-cycl obuto[cd]pentalene (Mirex), methoxychlor, toxaphene and hexachlorobenz ene (HCB), Aroclors 1248 and 1254 as well as ten individual polychlori nated biphenyl (PCB) congeners. Extractable organic matter (EOM) level s ranged from 48.0 to 133.0 mg/g, and from 33.0 to 73.0 mg/g in bivalv es and fish, respectively. 2,2-bis(p-Chlorophenyl)-1,1-dichlorethylene (p,p'-DDE) dominated other 2,2-bis(p-chlorophenyl)-1,1,1-trichloroeth ane (DDT) analogues in fish (2.0-4.0 ng/g), 1-chloro-2,2-bis(p-chlorop henyl)ethylene (DDMU) dominated in the bivalve, its concentration rang ing from 9.0 to 15.0 ng/g. The concentration of heptachlor was negligi ble, while endrin and dieldrin were the dominant cyclodienes, occurrin g in high levels in fish (0.6 and 1.3 ng/g) and bivalves (1.5 and 2.4 ng/g), at Gamasa and Demiatta, respectively. The Aroclor 1248 level wa s two-to threefold that of Aroclor 1254. As far as the individual PCBs are concerned, less chlorinated biphenyl congeners (from mono- to pen ta-chloro-biphenyls) were less concentrated except for PCB 200 and PCB 206. Toxaphene was detected at all three locations, at a maximum leve l of 9.7 ng/g in bivalves from Demiatta.