Instrumental and bioanalytical measures of persistent organochlorines in blue mussel (Mytilus edulis) from Korean coastal waters

Blue mussels (Mytilus edulis) collected from 34 locations along the south a nd east coast of Korea were analyzed for polychlorinated biphenyls (PCBs) a nd organochlorine (OC) pesticides. Maximum concentrations of PCBs and total OC pesticides were 98.5 and 20.5 ng/g, wet weight, respectively. Extracts were fractionated by Florisil chromatography and each fraction was screened for dioxin-like activity in vitro, using recombinant rat hepatoma cells (H 4IIE-luc). Fraction 2 (F-2), which contained hexachlorocyclohexanes, chlord anes, p,p'-DDD, and p,p'-DDT, generally elicited significant dioxin-like ac tivity compared to control, whereas Fraction 1 (F-1), which contained PCBs, p,p'-DDE, and hexachlorobenzene, did not. The greatest magnitude of dioxin -like response observed was 44% of the maximum response elicited by a 2,000 pM 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) standard. The relatively low magnitudes of dioxin-like response observed for F-1 samples were consisten t with the relatively low PCB concentrations. At concentrations equal to th e maximum observed in the mussel samples, neither individual OC pesticides nor a mixture of OC pesticides yielded a significant dioxin-like response i n the H4IIE-luc assay. Thus, the concentrations of OC pesticides in F-2 did not appear to have accounted for the dioxin-like activity observed. This s uggests the presence of unidentified and/or unknown, acid-stable, dioxin-li ke compounds in F-2. This study suggests that in vitro bioassays are useful in assessing the contamination of mussels collected from coastal marine lo cations.