CAREER: Anaerobic Degadation of Polycyclic Aromatic Hydrocarbons in Marine Harbor Sediments

University Of Maryland, College Park, College Park MD

Investigators

Abstract

9984285 Pulliam Holoman Polycyclic aromatic hydrocarbons (PAHs) tend to associate strongly with organic matter in sediments, which are normally anaerobic. The widespread distribution of PAHs in these sediments has led to the need for efficient, cost-effectifve methods for the remediation of PAH-contaminated sediments. Aerobic degradation of simple aromatic hydrocarbons has been well characterized, and in recent years, a few studies investigating the anaerobic degradation of simple PAHs such as naphthalene and phenanthrene (2 rings and 3 rings, respectively) have been reported. To date, no studies have demonstrated the anaerobic biodegration of 4- and 5-ring PAHs, such as pyrene and benzo[a]pyrene. This research will investigate the anaerobic degradation of PAHs by microorganisms isolated from marine harbor sediments that have been heavily contaminated with PAHs. The research objectives include isolation and characterization of naturally-occurring microbes with anaerobic PAH-degradative potential, elucidation of the metabolic pathways of PAH biodegradation and its important enzymes, development of unique biosensors for rapid monitoring of PAH degradation potential and activity, both in the laboratory and in situ, the use of bench-scale bioreactors to study anaerobic PAH degradation in complex mixtures and the development of mathematical models to predict the rate and extent of PAH degradation in the bioreactors.. The results of this research will provide guidance for the engineering design of processes to decontaminate harbor sediments containing high molecular weight PAHs. The educational plan has three components. First, the research will be integrated into a combined senior-level undergaduate and graduate course that the PI has developed. The course focuses on the design of innovative solutions to complex environmental problems requiring an interdisciplinary approach. Second, the PI will design an anaerobic PAH-degradation reactor that will integrate the results of this research as well as allow process safety to be introduced and evaluated in the undergraduate chemical engineering laboratory. Third, the PI will develop one-day workshop seminars to target female and other underrepresented minority middle and high school students. The goal of these workshops will be to introduce students from local schools to environmental research applied to the nearby Chesapeake Bay. ***