@inbook {51933,
	title = {Coupling lead isotopes and element concentrations in epiphytic lichens to track sources of air emissions in the Athabasca oil sands region},
	year = {2013},
	note = {IN:  Percy K.E. (Ed.). Alberta oil sands: Energy industry and the environment. Elsevier Amsterdam, The Netherlands. Developments in Environmental Science 11.  pp. 343-372.},
	pages = {29 pages },
	publisher = {Elsevier Ltd},
	organization = {Elsevier Ltd},
	address = {Amsterdam, The Netherlands},
	abstract = {A study was conducted that coupled use of element concentrations and lead (Pb) isotope ratios in the lichen Hypogymnia physodes collected during 2002 and 2008, to assess the impacts of air emissions from the Athabasca Oil Sands Region (AOSR, Canada) mining and processing operations. The lichens selected from the 2002 data set were from 15 samples sites collected on an N-S and E-W grid centered between the oil sands processing sites. The lichens selected for analysis in 2008 were collected using a stratified, nested circular grid approach radiating away from the oil sands processing sites, and included 121 sampling sites as far as 150km from the mining and processing operations. Spatial analysis indicates three main element groupings including a geogenic source (aluminum and others) related to oil sands mining, an oil processing source (vanadium and others), and a grouping that is likely related to biogeochemical processes (manganese and others). An exponential decrease in concentration of the geogenic grouping of elements versus distance from the mining sites was found, whereas near source concentrations of elements typically associated with oil processing are more homogeneous spatially than the geogenic elements. The mining and oil processing related element groupings are superimposed over the elemental signature that reflects lichen biogeochemical processes. The ranges in Pb isotope ratios were similar in 2002 and 2008, suggesting that sources of Pb accumulated by the lichens did not change substantially between 2002 and 2008. The Pb isotope ratios from lichens collected beyond 50km from the mining and processing sites cluster into a grouping with a 207Pb/ 206Pb ratio of 0.8650 and a 208Pb/ 206Pb ratio near 2.095. This grouping likely reflects the regional background Pb isotope ratio signature. The lowering of the 207Pb/ 206Pb and 208Pb/ 206Pb ratios near the mining and processing operations indicates that other Pb sources, likely related to the oil sands mining and processing, are contributing to the Pb source signature. This assessment was confirmed through the analysis of source and stack samples. The Pb isotope ratios were a better predictor of the extent of the source contribution than the element concentrations because the Pb isotope ratios are not affected by either the metabolic processing of elements by the lichens or by moisture related controls on atmospheric deposition processes at the collection sites.The main goals for this project to determine (i) the efficacy of using Pb isotopes to assist in identifying the sources of atmospherically deposited air pollutants in the AOSR and (ii) whether coupling Pb isotopes with elemental concentrations can help to elucidate the causes for spatial differences in the accumulation of elements by epiphytic lichens in relation to emission sources were successful. An approach that couples Pb isotopes, spatial analysis, and element concentrations is recommended for future source attribution studies in the AOSR.
},
	keywords = {air emissions, analytical methodology, lichen, metals},
	url = {https://www.researchgate.net/profile/Matthew_Landis/publication/234840037},
	author = {Graney, Joseph R. and Landis, Matthew S. and Krupa, Sagar}
}
