Comparative kinetics for bioaccumulation of polychlorinated biphenyls by the polychaete (Capitella capitata) and fish (Mugil cephalus).

The bioaccumulation of Aroclors 1242, 1254, and 1260 from sediments by the polychaete (Capitella capitata) and from water by the mullet (Mugil cephalus) was measured in aquarium experiments and followed by clearance investigations. This allowed calculation of the bioaccumulation factor (KB), uptake rate constant (k1), clearance rate constant (k2), and derived half-life (t1/2). The k2 and t1/2 values were of comparable magnitude for each organisms, but k1 values, calculated for polychaetes on the basis of PCB concentrations in whole sediment, were considerably lower, as were the KB values similarly determined. Using the Freundlich equation, an expression was developed for KB assuming that uptake occurred from interstitial water. This expression required the use of empirically developed constants for sedimentary characteristics but gave values for k1 and KB comparable to the values obtained with the fish.