PCB-induced changes of a benthic community and expected ecosystem recovery following in situ sorbent amendment

Environmental Toxicology and Chemistry
By: , and 



The benthic community was analyzed to evaluate pollution-induced changes for the polychlorinated biphenyl (PCB)-contaminated site at Hunters Point (HP) relative to 30 reference sites in San Francisco Bay, California, USA. An analysis based on functional traits of feeding, reproduction, and position in the sediment shows that HP is depauperate in deposit feeders, subsurface carnivores, and species with no protective barrier. Sediment chemistry analysis shows that PCBs are the major risk drivers at HP (1,570 ppb) and that the reference sites contain very low levels of PCB contamination (9 ppb). Different feeding traits support the existence of direct pathways of exposure, which can be mechanistically linked to PCB bioaccumulation by biodynamic modeling. The model shows that the deposit feeder Neanthes arenaceodentata accumulates approximately 20 times more PCBs in its lipids than the facultative deposit feeder Macoma balthica and up to 130 times more than the filter feeder Mytilus edulis. The comparison of different exposure scenarios suggests that PCB tissue concentrations at HP are two orders of magnitude higher than at the reference sites. At full scale, in situ sorbent amendment with activated carbon may reduce PCB bioaccumulation at HP by up to 85 to 90% under favorable field and treatment conditions. The modeling framework further demonstrates that such expected remedial success corresponds to exposure conditions suggested as the cleanup goal for HP. However, concentrations remain slightly higher than at the reference sites. The present study demonstrates how the remedial success of a sorbent amendment, which lowers the PCB availability, can be compared to reference conditions and traditional cleanup goals, which are commonly based on bulk sediment concentrations.

Study Area

Publication type Article
Publication Subtype Journal Article
Title PCB-induced changes of a benthic community and expected ecosystem recovery following in situ sorbent amendment
Series title Environmental Toxicology and Chemistry
DOI 10.1002/etc.574
Volume 30
Issue 8
Year Published 2011
Language English
Publisher Society of Environmental Toxicology and Chemistry
Contributing office(s) Branch of Regional Research-Western Region, San Francisco Bay-Delta, Toxic Substances Hydrology Program
Description 8 p.
First page 1819
Last page 1826
Country United States
State California
Other Geospatial San Francisco Bay
Google Analytic Metrics Metrics page
Additional publication details