Edible portions of 12 marine organisms from several areas of the Adriatic Sea, Italy, were collected during Spring 1997 and analysed for 32 organochlorine pesticides residues and 27 polychlorobiphenyl congeners. Only eight organochlorine pesticides - hexachlorobenzene (HCB), hexachlorocyclohexane (HCH) isomers, diphenyl-dichloro-trichloroethane (DDT) group, dieldrin - were determined at levels in the range <0.01-19.88 ng g(-1) wet weight, with 1,1'-dichloro-2,2'-bis(4-chlorophenyl)ethylene (DDE) being the more relevant single organochlorine. The contamination by organochlorine pesticides was comparable in organisms from the North, Centre and South Adriatic. Polychlorinated biphenyls (PCBs) were determined at levels in the range <0.05-14.46 ng g(-1), with CB 101, 118, 138, 153, 180 and 187 being more relevant (penta-, hexa- and hepta-chlorinated congeners). The sum of PCBs congeners determined were in the range 1.18-69.05 ng g(-1). The contamination by PCBs is more relevant in organisms from the North Adriatic Sea owing to the antropic discharge from major rivers such as Po and Adige that flow through highly industrialized and densely populated areas.