Deposition Mapping of Polycyclic Aromatic Compounds in the Oil Sands Region of Alberta, Canada and Linkages to Ecosystem Impacts

Abstract

This study produced gridded deposition estimates of polycyclic aromatic compounds (PACs), including 17 polycyclic aromatic hydrocarbons (PAHs), 21 alkylated PAHs (alk-PAHs), and 5 dibenzothiophenes (DBTs), over the oil sands region of Alberta, Canada and surrounding communities. Gridded annual total deposition of PACs in 2011 ranged from 55 to 175 000 μg m −2 yr −1 and the mean and median fluxes were 1700 and 760 μg m −2 yr −1 , respectively. The domain-wide mean dry and wet deposition were 600 and 1100 μg m −2 yr −1 . PAHs, alk-PAHs and DBTs contributed 19%, 74%, and 7% to the total dry deposition, and 42%, 49%, and 9% to the total wet deposition. Dominant chemical species contributing to total deposition were naphthalene, retene and phenanthrene for PAHs and C2-benz[a]anthracene/triphenylene/chrysene, C2-fluoranthene/pyrene and C2-fluorene for alk-PAHs. The highest PAC deposition was found over the surface mineable area, which received 9 times the deposition flux of outlying areas. Additional deposition hotspots were also observed south of the surface mineable area notably over in situ bitumen production sites. The deposition of alk-PAHs impacted a more extensive area than that of PAHs or DBTs. This result suggests that atmospheric deposition is a key process in wildlife exposure to PACs across the region.

Exploring the Influence of Industrial and Climatic Variables on Communities of Benthic Macroinvertebrates Collected in Streams and Lakes in Canada’s Oil Sands Region

“…In alignment with, but more specific than much of the previous work [7,8,10,11,[21][22][23]74,75], the analyses presented here suggests a common influence of FPU at the Suncor Basemine on benthic invertebrates in the OSR. Mechanistically, the common regional associations between BMIIs and SBM-FPU may be associated with the emission and deposition of metal-laden petcoke fly ash originating from Suncor's coke-fired power plant [6,[13][14][15].…”

“…Although larger particles are present in the summer suggesting contributions from dust [17][18][19]78], the size distributions of particles in snow [79,80], the particle sizes and chemical composition of petcoke fly ashes [13][14][15]81], the efficiency of generic ESPs [82], and size distributions of particles emitted from stacks [27] suggest the influence of petroleum coke combustion on the deposition of some CoCs in the OSR. Based on the results here, many studies detecting changes in the deposition of CoCs may be identifying petroleum coke fly ash from Suncor's coke-fired power plant [7,10,11,20,22,23,33,75,83,84] which, via the component CoCs [85,86], may also be influencing benthic communities in the OSR.…”

Potential Influence of Sewage Phosphorus and Wet and Dry Deposition Detected in Fish Collected in the Athabasca River North of Fort McMurray

“…While other potential sources of variation near oil sands facilities are also possible, such as minor delivery of CoCs via seepage of water from tailings ponds or the substantive influence groundwaters naturally in contact with bitumen [21,34,71,72], within the oil sands region, atmospheric deposition is considered a primary exposure pathway linking industrial development and the ambient environment [58]. For example, work in the OSR also suggests rain is an efficient scavenger of some contaminants, such as Hg [57] and polyaromatic compounds [73].…”

“…We further augmented the descriptive models using other available data. The wet and dry deposition has been postulated as a primary effect pathway linking OSIA and the environment [38,57,58]. Furthermore, while the influence of precipitation is correlated with discharge and temperature, these variables are not co-linear (Supplementary Figure S1) suggesting a unique and possible role of local precipitation.…”

Advances in science and applications in air pollution monitoring: A case study on oil sands monitoring targeting ecosystem protection

“…The CR describes improvements to the GEM-MACH (Global Environmental Multi-scale -Modeling air quality and Chemistry) model's ability to estimate air pollutant concentrations and deposition patterns in the OSR, including the results of the TERRA (Top-down Emission Rate Retrieval Algorithm) model emission estimates derived from aircraft measurements during the period of Aug. 13 to Sept. 7, 2013. This work (Cheng et al 2018;Li et al 2017;Zhang et al 2018) improved the understanding of air pollutant emissions and transport associated with oil sands operations. Data from the top-down aircraft measurements improved air modeling capabilities and provided key information for understanding the contribution of oil sands activities to ambient air quality and atmospheric deposition (Akingunola et al 2018;Gordon et al 2018;Russell et al 2019;Stroud et al 2018;Whaley et al 2018).…”