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 and nearby areas. This report describes the levels of metal contaminants and selected biomarkers in flounder from Fish Day, 1996. Mean age for males and females was 3.5 years, which is lower than the age reported for fish collected during previous efforts. Body weight1body 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. Environmental Protection Agency designations for marine fish liver and muscle tissue in all animals from all sites. Male flounder from Boston Harbor had significantly higher liver Cd levels than female flounder from Cape Cod and Boston Harbor. Female flounder from Boston Harbor showed significantly less metallothionein (MT) protein and lowerliver metal levels than those from Cape Cod. Metallothioncin mRNA did not significantly differ between sites nor did MT protein or mRNA between males and females from Boston Harbor. Cytochrome P450 2E1 (CYP2E1)-like and CYP1Al 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 optimal temperature(s), Boston Harbor females had significantly higher CYP2E1 -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 correlationfor all fish between CYP2E1 -like activity at ambient temperature and percent liver lipid. No differences were observed for liver lipid and microsomal protein between any of the groups. Liver glycogen showed a sex-dependent difference for the Boston Harbor group with levels in females significantly higher than males. These differences in contaminant levels and biomarkers are discussed within the context of data [ABSTRACT FROM AUTHOR]