Assessment of sublethal pollutant impact on flounders in an industrialised estuary using hepatic biochemical indices

Flounder Platichthys flesus from a pollution gradient in the Forth estuary, Scotland, were analysed for specific cytochrome P-450 and metal-binding protein induction as an indication of sublethal impact of organic xenobiotics and Group IIB metals respectively.Hepatic ethoxyresorufin O- deethylase (EROD) activity in fish from a reference site was around 9 nmol (g liver)-' min-l and increased up to 9-fold in the area near discharges from a major petrochemical complex.Hepatic metallothionein (MT) content rose from 20 pg (g liver)-' at the uppermost site by ca 19-fold near the petrochemical complex.The study further demonstrates the validity of biochemical measurements for the assessment of pollutant impact in an estuarine environment.