Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/4/2008
Publication Date: 11/16/2008
Citation: Shelver, W.L., Caesar, T. 2008. Isolation and Identification of Dioxin Degrading Bacteria Found in Soils Contaminated with PCDDs/PCDFs [Abstract].Society of Environmental Toxicology and Chemistry (SETAC) 29th Annual Meeting Abstract Book, November 16-20, 2008, Tampa, FL. RP116, page 325. Interpretive Summary: Abstract only - no interpretive summary needed.
Technical Abstract: There is a need to identify bacteria that can degrade environmental contaminants; a fruitful place to identify such bacteria is within contaminated soil. The dioxin content and congener distribution in soils collected from adjacent to old railroad track that were treated with pentachlorophenol (PCP) was isolated by first sonicating in acetone/toluene followed by alumina, tri-phase silica, and carbon column cleanup. An isotope dilution method following EPA method 1613 using high-resolution gas chromatography-high resolution mass spectrometry demonstrated these soils to have elevated dioxin levels that matched with the dioxin contamination pattern in PCP treated wood. It was hypothesized that bacteria from these soils might use dioxins as an energy source thus being good candidates for bio-remediation tools to decrease dioxin levels in the soils. The predominant bacteria from two sites with high and low dioxin contamination were isolated from whole soil and identified by cellular fatty acids, derivatized to methyl esters (FAMEs) profiling. High proportion of Pseudomonas veroni and Pseudomonas fluorescens (biotype A and B) were found in the high dioxin contaminated sites compared to the low dioxin contaminated sites where Fluorescens putida biotype A appeared to predominate.