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KSCS FOR A PAH AND PCB ASSOCIATED WITH A MARINE SEDIMENT AMENDED WITH SEVERAL TYPES OF SOOT CARBON
Citation:
Burgess, R M., S Ryba, R Tien, M. M. Perron, AND M Cantwell. KSCS FOR A PAH AND PCB ASSOCIATED WITH A MARINE SEDIMENT AMENDED WITH SEVERAL TYPES OF SOOT CARBON. Presented at Society of Environmental Toxicology and Chemistry Annual Meeting, Salt Lake City, UT, November 16-20, 2002.
Description:
Soot carbon (SC) originates from the combustion of fossil fuels and biomass and is found in sediments around the world. SC comprises up to 30% of organic carbon in sediment and is now commonly recognized as a phase which must be considered when predicting the environmental partitioning of organic contaminants. This is primarily because the presence of SC in sediments appears to increase the partitioning of some contaminants. In this study, we amended a marine sediment with soot carbon from various sources, a non-soot carbon, and a non-carbon matrix. We then conducted equilibration studies with 14C fluoranthene (PAH) and 3H 2,4'-dichlorinated biphenyl (PCB). Soot carbon source materials included raw and aged automotive diesel soot, coal dust, class ?F' coal fly ash, and an organic carbon enriched coal fly ash. Non-soot carbon and non-carbon materials included Aldrich humic acid and muffled beach sand, respectively. SC concentrations in amended sediment ranged from 0.05 to 15.2% and organic carbon (OC) concentrations ranged from 0.21 to 18.4%. In general, PAH partitioning was most strongly correlated to SC concentrations while PCB partitioning was primarily associated with sediment OC content. Log SC normalized partition coefficients (Ksc) for PAHs were > 6.0 and PCB Ksc values were approximately 5.5. These Kscs were about one order of magnitude greater than the corresponding Kocs for these chemicals. These results demonstrate PAH partitioning is strongly influenced by SC of various types while the partitioning of a non-planar, hydrophobic contaminant like the PCB used in this study was affected most significantly by sediment organic carbon.