Phillip M Fedorak

..This work showed that each MFT and CT sample has the potential to become methanogenic, but in the absence of exogenous electron donors, the added sulfate can inhibit methanogenesis for a long time...

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..This study describes one set of conditions for continued sulfidogenesis during nitrate reduction, with important implications for nitrate control of sulfide production in oil fields...

..Current study findings could influence extraction process, MFT management, and reclamation options...

..It appears that DAP-NRB would play a minor role in the consumption of nitrate injected into oil field waters for the control of hydrogen sulfide production...

..This discrepancy may result from heterogeneity and density of the tailings, presence of nutrients in the microcosms, and/or overestimation of the readily biodegradable fraction of the naphtha in MLSB tailings...

..01 mg L(-1) compared to 1 mg L(-1) for the FTIR method. The results indicated that the GC-MS method is more selective for naphthenic acids, and that the FTIR method overestimates their concentrations...

..The toxicity of ozonated OSPW to higher organisms needs to be assessed, but there is promise that this technique could be applied to accelerate the bioremediation of large volumes of OSPW in Northern Alberta, Canada...

..Four different species of fish (two fish of each species) were collected from the Athabasca River near two oil sands mining and extraction operations. No free naphthenic acids were detected in the muscle or liver of these fish...

..GC-MS results demonstrated that biodegradation changes the composition of the complex mixture of these NAs and that the lower molecular weight acids (with n = 5-13) were degraded more readily than the high molecular weight acids...

..This paper reviews a variety of analytical methods and their application to assessing biodegradation of naphthenic acids...

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..The results demonstrate that ozonation is complementary to microbial biodegradation, and the process remains a promising water reclamation strategy for the oil sands industry...

..Thus, the presence of naphthenic acids in waters cannot be solely attributed to petroleum or petroleum industry activities...

..2 to 2.8mgkg(-1). The GC-MS results from one wild fish presented a unique problem. However, with additional work it was concluded that the NAs concentration in this fish was <0.1mgkg(-1)...

..We conclude that the source of the NAs is important when interpreting odor threshold data and that the two commercial preparations of NAs that were tested do not represent oil sands waters' tainting potential...

..Classical and oxy-NAs are components of OSTWAEO, but this term would not be as misleading as "naphthenic acids"...

..Methane was not detected throughout the incubation in samples amended with sulfate. The increase in AVS supports sulfide incorporation into the solid phase, however, the plateau after 39 d suggests a secondary fate of reduced sulfide...

..Moreover, the results indicate that biodegradation studies using commercial NAs alone will not accurately reflect the potential biodegradability of NAs in the oil sands tailings waters...

..GC-MS analysis showed that ozonation resulted in an overall decrease in the proportion of high molecular weight naphthenic acids (n> or = 22)...

..JVH1 therefore possesses broader sulfur extraction abilities than previously reported, including not only sulfidic compounds but also some thiophenic species...

..Data analyses showed that there was no evidence from the consumer preference rankings that the taste of the fish from the Athabasca River was preferred less than the taste of fish from two other water bodies in Alberta...

..This statistical approach can be applied to data collected by other mass spectrometry methods...

..Using low- and high-resolution MS to detect the ion C(15)H(27)O(2)Si(+) (nominal m/z=267) is an excellent indicator of the presence of naphthenic acids at concentrations > or =10microgL(-1)...

..Analyses of 58 oil sands water samples showed that the naphthenic acids concentrations determined by FTIR were on average 11% higher than those determined by HPLC...

..These findings may influence decisions regarding extraction processes and long-term management of MFT, and they suggest that intrinsic, methanogenic metabolism of these n-alkanes may occur in other anoxic environments...

..Overall, the GC-MS method appears to overestimate the relative proportion of low-molecular-mass acids...

..It is anticipated that these data will facilitate development of strategic solutions for remediating billions of cubic meters of OSPW stored, or predicted to be generated, in Northern Alberta...

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..This study is the first to demonstrate the biodegradation potential of microorganisms from rhizosphere soils to biodegrade naphthenic acids...

..This is the first investigation in which changes in the fingerprint of the NA fraction of process-affected waters from the oil sands operations has corresponded with measured toxicity in these waters...

..Although the surface area of the secondary more than doubled, the average number of airborne microorganisms in this part of the plant in 2004 was about 1% of that in 1976...

..strain RM6. In pure culture, this isolate mineralized 2,2'-dithiodibenzoic acid, releasing 59% of the carbon as carbon dioxide and 88% of the sulfur as sulfate...

..Overall, PFPS is an excellent tool for isolating bacteria capable of cleaving subterminal C-S bonds within alkyl chains. The type of desulfurization displayed by JVH1 differs significantly from previously described reaction results...