USE OF HEPATIC MFO AND BLOOD ENZYME BIOMARKERS IN SAND FLATHEAD (PLATYCEPHALUS-BASSENSIS) AS INDICATORS OF POLLUTION IN PORT PHILLIP BAY, AUSTRALIA

Hepatic ethyoxycoumarin O-deethylase (ECOD) and ethoxyresorufin O-deet hylase (EROD) activities, and serum sorbitol dehydrogenase (s-SDH) wer e measured over 3 years in sand flathead (Platycephalus bassensis) col lected from Port Phillip Bay, Australia. Significant enzyme induction generally occurred in regions closest to highly industrial and urbaniz ed areas relative to undeveloped reference areas of the bay. High s-SD H levels were associated with lower hepatic microsomal ECOD and EROD l evels. There were no sex differences in liver ECOD or s-SDH in any sam pling period, and sex differences in EROD activity,were only significa nt in September 1990, when males had significantly higher activities t han females (47.0 pmol min(-1) mg protein(-1) compared with 28.4 pmol min(-1) mg protein(-1), respectively). Liver EROD activity in sand fla thead from Hobsons Bay was positively correlated with total freshwater input, mainly from the Yarra River, suggesting PAHs as a possible cau se of the observed induction.