Polychlorinated dibenzo-p-dioxins, dibenzofurans and biphenyls in crucian carp (Carassius auratus) from rivers in Korea during 2000-2004.

Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were analyzed in freshwater fish (crucian carp) taken from 16 locations in nine rivers and a wetland in Korea, during 2000-2004. Dioxin-like polychlorinated biphenyls (DL-PCBs) were also analyzed in the same samples but over shorter period (2002-2004). Concentrations on a wet weight basis for 3 years (2002-2004) ranged from below the detection limit (DL) to 0.36 pg TEQ g(-1) wet wt. for PCDDs, below the DL to 2.0 for PCDFs, and from 0.02 to 1.9 for DL-PCBs, with a mean of 0.07, 0.33 and 0.83 pg TEQ g(-1) wet wt., respectively. The proportions of PCDDs, PCDFs and DL-PCBs in the total dioxin TEQ for 2002-2004 were 7%, 26% and 67%, respectively. While the temporal trend showed a significant decrease in PCDDs/DFs concentrations over the 5-year study period, DL-PCBs did not show significant change in concentration over the 3-year period. The results suggest that DL-PCBs concentrations should be determined when total dioxin TEQ is analyzed in freshwater fish.