ACCUMULATION OF ORGANOCHLORINE PESTICIDES AND PCBS BY SEMIPERMEABLE-MEMBRANE DEVICES AND MYTILUS-EDULIS IN NEW BEDFORD HARBOR

We deployed semipermeable membrane devices (SPMDs) and transplanted bl ue mussels (Mytilus edulis) side-by-side at five sites in New Bedford Harbor, MA. A good correlation was obtained between accumulation in th e SPMDs and the caged mussels, with r(2) values ranging from 0.57 to 0 .85 for individual pesticides (n = 16) and from 0.81 to 0.96 for indiv idual PCB congeners (n = 20). An excellent correlation also was found between the log K-ow and the log BAF (bioaccumulation factor in mussel s) and between the log K-ow and log AF (accumulation factor in SPMDs). Accumulation in the mussels was approximately 2-fold higher than in t he SPMDs when concentrations were expressed on a lipid basis. These co rrelations are significantly better than any reported previously and p robably result from modifications that we made to the original design of the SPMD. A close examination of accumulation into SPMDs demonstrat es that the uptake rate and equilibrium status of an SPMD can be easil y manipulated by modifying membrane thickness, surface area, and lipid substrate volume. Knowledge of these parameters and their effect on S PMD uptake rates is critical to the interpretation of SPMD data and ca n be used to optimize the design of SPMDs for specific applications.