Monitoring organochlorines with semi-permeable membrane devices (SPMDs) and mussels (Mytilus edulis) in Corio Bay, Victoria, Australia

Semi-permeable membrane devices (SPMDs) and mussels (Mytilus edulis) were deployed side-by-side at seven sites in Corio Bay, Victoria, Australia, for a period of 60 days in order to test their relative abilities to monitor a known gradient of organochlorine contaminants, including polychlorinated biphenyls (PCBs) and pesticides. Both SPMDs and mussels provided similar information on the relative levels of organochlorine contamination. However, the profiles of PCBs differed: SPMDs suggested that lower chlorinated PCBs dominated in the water column, whilst mussel data implied essentially the reverse. These differences were attributed to contaminant solubility, partitioning of contaminants on suspended particulates, and possible biotransformation. The accumulation by the SPMDs of many early eluting and unidentified halogenated hydrocarbons, which were primarily absent in the mussels, suggested that the SPMDs may be capable of more precisely defining the presence of certain contaminants in the water column.