MFO Induction of Three Australian Fish Species

( ) ABSTRACT: The use of mixed function oxygenase MFO enzymes as a biomarker of pollution in Port ( ) Phillip Bay was investigated in three indigenous fish species, sand flathead Plathycephalus bassensis , ( ) ( ) bluethroat wrasse Notalabrus tetricus , and sixspine leatherjacket Meuschenia freycineti . Investigation of the relative MFO induction potential was performed by intraperitoneally injecting each experimental X X ( ) fish species with 100 mg/kg of 3,3 ,4,4 ,5-pentachlorobiphenyl PCB 126 using corn oil as a carrier. Hepatic induction was fluorimetrically measured by the activity of 7-ethoxyresorufin O-deethylase ( ) EROD activity 10 days post-injection. Of the three species tested, the sand flathead was selected as the most suitable indicator species for its high MFO induction potential and desirable characteristics related to its population biology. Bluethroat wrasse appeared relatively uninducible by PCB 126, while sixspine leatherjacket demonstrated a medium induction potential but was unsuitable as a biomonitoring tool because of its scarcity and distribution limited to reef beds. Q 2000 by John Wiley & Sons, Inc. Environ Toxicol 15: 1]7, 2000