@article {91,
	title = {Assessing microbial carbon sources and potential PAH degradation using natural abundance 14C analysis},
	journal = {Environmental Pollution},
	volume = {175},
	year = {2013},
	note = {id: 2268},
	pages = {125-130},
	abstract = {Natural abundance 14C analysis was applied to PLFAs collected from an industrial site in southern Ontario in order to assess microbial carbon sources and potential PAH biodegradation in soils. Δ14C of microbial phospholipid fatty acids (PLFA) at the site ranged from +54{\textperthousand} to -697{\textperthousand}. Comparison of these values to surrounding carbon sources found that microbial carbon sources were derived primarily from vegetation and/or natural organic matter present in the soils rather than PAHs. This study highlights that microbes are able to utilize almost all available pools of organic matter including older pools which are thought to contain recalcitrant compounds. Furthermore, it shows that even with the presence of an active microbial community, there may be little biodegradation of PAHs. This study illustrates challenges in assessing microbial activity in the environment and the advantage of using natural abundance 14C analysis as a tool to elucidate microbial carbon sources.},
	issn = {0269-7491},
	doi = {10.1016/j.envpol.2012.12.020},
	url = {http://www.sciencedirect.com/science/article/pii/S0269749112005453},
	author = {Mahmoudi, Nagissa and Fulthorpe, Roberta R. and Burns, Leanne and Mancini, Silvia and Slater, Greg F.}
}
@article { ISI:000279304700045,
	title = {Assessing Microbial Uptake of Petroleum Hydrocarbons in Groundwater Systems Using Natural Abundance Radiocarbon},
	journal = {ENVIRONMENTAL SCIENCE \& TECHNOLOGY},
	volume = {44},
	number = {{13}},
	year = {2010},
	month = {JUL 1},
	pages = {5092-5097},
	type = {Article},
	abstract = {Carbon sources utilized by the active microbial communities in shallow groundwater systems underlying three petroleum service stations were characterized using natural abundance radiocarbon ((14)C). Total organic carbon (TOC) Delta(14)C values ranged from -314 to -972 parts per thousand and petroleum-extracted residues (EXT-RES) ranged from -293 to -971 parts per thousand. Phospholipid fatty acids (PLFAs)-biomarkers for active microbial populations-ranged from -405 to -885 parts per thousand and a comparison of these values with potential carbon sources pointed to significant microbial assimilation of (14)C-free fossil carbon. The most (14)C depleted PLFAs were found in the samples with the highest concentrations of total petroleum hydrocarbons (TPHs). A radiocarbon mass balance indicated up to 43\% of the carbon in microbial PLFAs was derived from TPHs, providing direct evidence for biodegradation at two of three sites. At lower levels of TPHs. Delta(14)C values of PLFAs were generally similar to or more enriched than all other carbon in the system indicating microbial utilization of a more (14)C-enriched carbon source and no resolvable evidence for microbial incorporation of petroleum-derived carbon. Results from this study suggest that it is possible to delineate petroleum biodegradation in groundwater systems using these techniques even in complex situations where there exists a wide range in the ages of natural organic matter (i.e., EXT-RES).},
	issn = {0013-936X},
	doi = {10.1021/es100080c},
	author = {Ahad, Jason M. E. and Burns, Leanne and Mancini, Silvia and Slater, Greg F.}
}
