Do seasonal changes affect enzymatic biomarkers induction by pollutant in flatfish

Abstract

Most biological indicators can be expected to vary with natural factors such as age, sex, maturity, season and reproductive status (all of which themselves co-vary) and enzymatic biomarkers are no exception. For example, the dependence of EROD (ethoxyresorufin O-de-ethylase) activity in fish liver, which is used widely as a biomarker of organic contaminant exposure, on sex and season has been shown explicitly. In this study, the variation of ChE in marbled sole from the Haegeumgang \\'reference\\' site was investigated. Masan Bay is a large harbour in the southern part of Korea which receives a wide range of industrial and sewage discharges and wastes from shipping activity. Previous studies have shown that there are high concentrations of PCBs and TBT (among other chemicals) in water and in sediments. We choose the flatfish for monitoring fish. Since most contaminants of concern are sediment-bound, the selection criteria were that the fish should be preferably a benthic species (thus maximizing its exposure to contaminated sediment). Fish from Masan Bay have higher CYP1A1 mRNA induction and EROD activity than those from the Haegeumgang in spring and but Brain-AChE were inhibited in Masan fish in spring but not later in the year. The results from this study suggest that Limanda yokahamae in Masan Bay may affect by other environmental factor.