Identification and environmental fate of novel halogenated polycyclic aromatic compounds in Canada's Oil Sands Region

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The Alberta Oil Sands (AOS) is the world's third largest reserve of crude oil with an estimated 165 billion barrels of oil recoverable given current technologies. The region contains naturally occurring mixtures of crude bitumen, sand, clay, ultrafine mineral solids and water that are rich in a soup of organic compounds the most notable of which are the polycyclic aromatic compounds (PACs). Because of their historical legacy, federal monitoring activities in Canada have focused on the polycyclic aromatic hydrocarbons (PAHs) and their alkylated analogs. However, it is known that the AOS region was once covered by sea water millions of years ago, which would have contained high concentrations of chloride and bromide ions. During the oil sand formation, the elevated pressures and temperatures of diagenesis and catagenesis combined with the catalytic activation of halides formed with abundant crustal elements Al and Fe created an environment conducive to organohalogen formation. We hypothesize that halogenated PACs would be detectable in biological samples from the AOS region. The overarching aim of the research program described here is to develop novel analytical techniques using state-of-the-art instrumentation to unearth new halogenated PAC (HPACs) in environmental samples from the AOS region. This is important because these compounds have not been identified before in the AOS region and there is a potential that these compounds could be more harmful to wildlife than ones not containing halogen atoms. Chlorine and bromine containing PACs and their alkylated derivatives will be the focus of this student-led research program. The new compounds identify in biological samples will drive the second major component of this research program. Specifically, we will examine how susceptible these compounds are to metabolism using a fish liver microsomal bioassay. Commercially available standards will be used as substrate to understand the metabolic conversion of these compounds to more polar metabolites. In addition to understanding how quickly they metabolize, my HQP team will identify the metabolites formed during the incubation bioassay. The identification of HPACs in wildlife from the AOS region and the metabolites formed in fish will lead to future research activities on the persistence, bioaccumulation and toxicities of these compounds that our group (and others) will explore.