You are here:
Comparison of Passive Sampling Devices for Measuring Dissolved PCBs in the Water Column of a Marine Superfund Site
Citation:
BURGESS, R. M., Y. Zhang, M. P. McKee, R. Lohmann, P. J. Luey, C. L. Friedman, J. P. SCHUBAUER-BERIGAN, AND L. Lefkovitz. Comparison of Passive Sampling Devices for Measuring Dissolved PCBs in the Water Column of a Marine Superfund Site. Presented at SETAC North American 29th Annual Meeting, Tampa, FL, November 16 - 20, 2008.
Impact/Purpose:
This research evaluates several recently developed tools for measuring the release of sediment contaminants into the water column. The analysis be will be useful for evaluating the effects of environmental remediation on water column exposure conditions.
Description:
The presence of contaminated sediments in aquatic environments results in several potential sources of ecological risk. These risks include the release of contaminants into the water column causing exposure to pelagic organisms. Possible adverse biological effects of this exposure include trophic transfer of contaminants to fish, wildlife and humans. Biomonitoring with water column deployed organisms is frequently used to quantify the magnitude of this type of exposure. More recently, several passive sampling technologies have been developed to complement biomonitoring including semi-permeable membrane devices (SPMDs), solid phase microextraction (SPME) and polyethylene devices (PEDs). In principle, these samplers collect organic contaminants only from the dissolved phase and thus contaminants bioavailable to organisms. In this study, the uptake of 18 polychlorinated biphenyls (PCBs) by SPMDs, SPME and PEDs was compared in deployments at a marine Superfund site (New Bedford Harbor, MA, USA). Deployments were performed at two stations for 7, 14, 21 and 29 days to evaluate PCB uptake kinetics and equilibrium concentrations. After 29 days of deployment, concentrations in passive samplers compared well to one another and, depending upon the congener, ranged from undetectable to 10,000 ng/mL. Further, when passive sampler PCB concentrations were used to calculate dissolved phase PCB concentrations, we found the samplers generated similar concentrations within a factor of two to three, ranging from undetectable to 100 ng/L. Finally, comparison of dissolved phase PCB concentrations based on the passive samplers to dissolved concentrations based on mussel concentrations from organisms deployed at the same stations in NBH showed the samplers under-predicted mussel exposures by a factor of two to five. Research is currently underway to better understand this difference between organism and sampler uptake. This study found, in general, the three passive sampling technologies generated similar results and suggests users of the samplers should consider the advantages and disadvantages of each in selecting which one(s) to deploy at contaminated sites.