Determination of laboratory and field elimination rates of polychlorinated biphenyls (Pcbs) in the freshwater mussel, Elliptio complanata.

摘要

Chemical elimination rate constants (k2) were determined for 41 polychlorinated biphenyl (PCB) congeners in dosed freshwater mussels, Elliptio complanta, following a 150-day laboratory depuration period. Congener-specific elimination rates were inversely dependent on the n-octanol/water partition coefficient (K(ow)) of the chemical according to the regression equation: logk2 = (-0.59 +/- 0.05) logK(ow) + (2.05 +/- 0.28) (R2 = 0.80, p < 0.001). PCB elimination rate constants in E. complanta were lower than reported for zebra mussels and green-lipped mussels but similar in magnitude and K(ow) dependence to data reported for American oysters. In order to validate the laboratory-derived PCB elimination rate constants, mussels dosed with [13C]PCB153 were allowed to depurate at one of the biomonitoring stations utilized in the Detroit River Biomonitoring Program and sampled at the same time intervals as laboratory animals. The field elimination rate constant for [13C]PCB153 was significantly greater than, but within a factor of 3 of, the laboratory elimination rate constant determined for unlabeled PCB153. This similarity in estimates of k2 for labeled and unlabeled PCB153 indicates that there is relatively little error introduced by using laboratory PCB elimination rate constants to estimate PCB153 toxicokinetics in mussels deployed at this field station. Elimination rate constants determined for PCBs in this species were lower and exhibited a stronger K(ow) dependence than elimination rate constants reported for selected PAHs. This suggests that E. complanata may possess some capability for PAH biotransformation.