BIOSTIMULATION OF POLYCHLORINATED BIPHENYL (PCB) DECHLORINATION IN SEDIMENTS OF ESCAMBIA BAY, FLORIDA
Brittany Elise Young
University of West Florida
Master of Science (MS), University of West Florida
2012
Metrics
11 File views/ downloads
67 Record Views
Abstract
Polychlorinated biphenyls (PCBs) contaminate the sediments of Escambia Bay in Pensacola, Florida. Given the right conditions anaerobic bacteria in sediments are capable of degrading PCBs by dechlorinating the molecule. The objective of this study is to assess, in the laboratory, conditions that may stimulate the naturally occurring bacteria in Escambia Bay to degrade the PCBs. The study may have implications for in situ treatment of contaminated sediments like these in Escambia Bay. Sediments were treated with three different electron donors (pyruvate, iron sulfide and elemental iron) that would stimulate the microbes to use the PCBs as an electron acceptor. Each treatment was tested in triplicate and allowed to dechlorinate for five months in an anaerobic environment. After five months, all three treatments resulted in a decrease in PCB concentration in sediment spiked with 2,3'4,4'5-pentachlorobiphenyl (congener 118) and in sediment spiked with Aroclor 1254. Unspiked PCB contaminated sediments showed a less consistent decrease in total PCB concentration for the various treatments. These results show that the bacteria found in Escambia Bay sediments can be stimulated to remediate the PCB contamination. Further research could develop this method into a viable in situ remediation strategy to address the contamination in Escambia Bay.