TEMPORAL STUDIES OF THE IMPACT OF THE BRAER OILSPILL ON INSHORE FERALFISH FROM SHETLAND, SCOTLAND

Activities of the petroleum-inducible mixed function oxygenase CYP1A ( EROD) were measured in livers of inshore demersal fish species at vari ous sites around the coast of Shetland to determine the sub-lethal imp act of oil spilled after the wreck of the tanker M.V. Braer in Januany 1993. Visible coastal pollution by the oil was only apparent for some two weeks after the incident and tissue PAH levels in muscle of gadoi d fish such as rockling from these areas were not elevated 3 months af terwards, while hepatic EROD activities were elevated some 7- to 9-fol d. A 6.5-fold elevation was still observed 5 months afterwards; howeve r, the levels had returned to those of fish from non-polluted environm ents 7 months after the incident and remained at baseline levels after the following winter's storm action. These data demonstrate the usefu lness of enzymatic analysis as a sensitive method for assessing the te mporal and spatial impact of an oil spill.