ASSESSMENT OF VARIOUS BIOMARKERS IN WINTER FLOUNDER FROM COASTAL MASSACHUSETTS, USA

Since 1992, the Massachusetts Water Resource Association has organized a Fish Day to assess the health of winter flounder in Boston Harbor a nd nearby areas. This report describes the levels of metal contaminant s and selected biomarkers in flounder from Fish Day, 1996. Mean age fo r males and females was 3.5 years, which is lower than the age reporte d for fish collected during previous efforts. Body weight/body length ratios were significantly higher in females versus males. Liver Cd, As , Zn, and Cu, and muscle As were all elevated relative to U.S. Environ mental Protection Agency designations for marine fish liver and muscle tissue in all animals from all sites. Male flounder from Boston Harbo r had significantly higher liver Cd levels than female flounder from C ape Cod and Boston Harbor. Female flounder from Boston Harbor showed s ignificantly less metallothionein (MT) protein and lower liver metal l evels than those from Cape God. Metallothionein mRNA did not significa ntly differ between sites nor did MT protein or mRNA between males and females from Boston Harbor. Cytochrome P450 2E1 (CYP2El)-like and CYP 1A1 activities were significantly higher at optimal temperatures than activity measured at field temperatures. No differences between groups were observed for either parameter at ambient temperatures, but at op timal temperature(s), Boston Harbor females had significantly higher C YP2E1-like and CYP1A1 activities than Boston Harbor males. A negative correlation was found between maximal CYP1A1 activity and age for the Boston Harbor fish and a positive correlation for all fish between CYP 2E1-like activity at ambient temperature and percent liver lipid. No d ifferences were observed for liver lipid and microsomal protein betwee n any of the groups. Liver glycogen showed a sex-dependent difference for the Boston Harbor group with levels in females significantly highe r than males. These differences in contaminant levels and biomarkers a re discussed within the context of data from previous Fish Days and th e implications for flounder health within Boston Harbor.