Dependency of polychlorinated biphenyl and polycyclic aromatic hydrocarbon bioaccumulation in Mya arenaria on both water column and sediment bed chemical activities

Abstract

The bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) by the filter-feeding soft-shell clam Mya arenaria was evaluated at three sites near Boston (MA, USA) by assessing the chemical activities of those hydrophobic organic compounds (HOCs) in the sediment bed, water column, and organisms. Polyethylene samplers were deployed to measure the activities of HOCs in the water column. Sediment activities were assessed by normalizing concentrations with sediment-water sorption coefficient values, including adsorption to black carbon in addition to absorption by organic carbon. Likewise, both lipids and proteins were considered in biota-water partition coefficients used to estimate chemical activities in the animals. Chemical activities of PAHs in M. arenaria were substantially less than those of the corresponding bed sediments in which they lived. In contrast, chemical activities of PCBs in M. arenaria often were greater than or equal to activities in the corresponding bed sediments. Activities of PAHs, such those of pyrene, in the water column were undersaturated relative to the sediment. However, some PCBs, such as congener 52, had higher activities in the water column than in the sediment. Tissue activities of pyrene generally were in between the sediment and water column activities, whereas activity of PCB congener 52 was nearest to water column activities. These results suggest that attempts to estimate bioaccumulation by benthic organisms should include interactions with both the bed sediment and the water column.

Organochlorine Pollutants in Western Antarctic Peninsula Sediments and Benthic Deposit Feeders

“…Passive sampling has been shown by previous studies to be a reliable and robust approach to obtain porewater concentrations of POPs (35)(36)(37)(38)(39)(40) . The detailed methods have been described elsewhere (37) .…”

“…Previous studies have shown that adsorption onto black carbon present in the sediments can greatly reduce the availability of POPs in the porewater (35)(36)(37)(38)(39) . Yet these studies have focused on areas strongly affected by human activities and have not investigated pristine locations such as Antarctic.…”

“…Passive samplers have been proven to be a robust sampling device to determine truly dissolved porewater concentration of POPs (35)(36)(37)(38)(39)(40) . The importance of black carbon for reducing bioavailability in the porewater thus can be assessed using passive sampler (35)(36)(37)(38)(39)(40) .…”

“…The importance of black carbon for reducing bioavailability in the porewater thus can be assessed using passive sampler (35)(36)(37)(38)(39)(40) .…”

Mechanistic sediment quality guidelines based on contaminant bioavailability: Equilibrium partitioning sediment benchmarks

“…As described previously, the EqP approach is based on the concept that the dissolved phase contaminant concentration in the sediment interstitial water reflects a chemical's activity and is a good surrogate for the bioavailable concentration [43,55]. To be clear, the interstitial water concentration is not the only exposure an organism living in the sediment experiences.…”