Sublethal effects of aged oil sands–affected water on white sucker (Catostomus commersonii)

Abstract

To investigate impacts of proposed oil sands aquatic reclamation techniques on benthic fish, white sucker (Catostomus commersonii Lacépède, 1803) were stocked in 2 experimental ponds-Demonstration Pond, containing aged fine tailings capped with fresh water, consistent with proposed end-pit lake designs, and South Bison Pond, containing aged unextracted oil sands material-to examine the effects of unmodified hydrocarbons. White sucker were stocked from a nearby reservoir at both sites in May 2010 and sampled 4 mo later to measure indicators of energy storage and utilization. Comparisons were then made with the source population and 2 reference lakes in the region. After exposure to aged tailings, white sucker had smaller testes and ovaries and reduced growth compared with the source population. Fish introduced to aged unextracted oil sands material showed an increase in growth over the same period. Limited available energy, endocrine disruption, and chronic stress likely contributed to the effects observed, corresponding to elevated concentrations of naphthenic acids, aromatic compounds in bile, and increased CYP1A activity. Because of the chemical and biological complexity of these systems, direct cause-effect relationships could not be identified; however, effects were associated with naphthenic acids, polycyclic aromatic hydrocarbons, ammonia, and high pH. Impacts on growth have not been previously observed in pelagic fishes examined in these systems, and may be related to differences in sediment interaction.

Population impacts in white sucker (Catostomus commersonii) exposed to oil sands–derived contaminants in the Athabasca River

“…This is in contrast to the present study where white sucker from the Muskeg River exhibited high condition factor relative to the Calling Lake reference site, but also had high condition factor relative to a previous study of white sucker in the region [19]. Thus, elevated somatic indices such as condition factor and liver size demonstrate that white sucker in the Athabasca river were not resource limited [19,24]. Thus, elevated somatic indices such as condition factor and liver size demonstrate that white sucker in the Athabasca river were not resource limited [19,24].…”

“…Reduced gonad weight in white sucker sampled from the Athabasca River did not correspond to changes in sex steroid concentrations. A previous study with white sucker exposed to aged oil sands process-affected water also did not show steroid hormone decreases [19], whereas an identical study with yellow perch showed impacts only in males [15]. For example, in contrast to the present study, fish exposed to pulp and paper effluent frequently demonstrate decreased circulating sex steroids [27].…”

“…Male white sucker in the Athabasca River had greater levels of hepatic EROD induction (2 fold) and equivalent concentrations of phenanthrene (3-fold) and benzo-[a]pyrene (28-fold) in bile than white sucker exposed to aged oil sands material in a previous study using comparable methods [19]. Male white sucker in the Athabasca River had greater levels of hepatic EROD induction (2 fold) and equivalent concentrations of phenanthrene (3-fold) and benzo-[a]pyrene (28-fold) in bile than white sucker exposed to aged oil sands material in a previous study using comparable methods [19].…”

Comparative toxicity of selected naphthenic acids, oil sands processed water and surface waters in rainbow trout hepatocytes: A gene expression study

“…There were also signs of epithelium degeneration in gills of fish exposed to OSPW compared to reference fish, supporting the notion that the toxicity of OSPW is diverse and not specific to a target organ. This was corroborated by another study, which examined the health status of white suckers exposed to aged OS tailings [11]. Fish maintained in aged OSPW had smaller testes and ovaries and reduced growth, which resulted from limited available energy and endocrine disruption, which was associated with increased CYP1A1 activity in the liver.…”

Overview of Existing Science to Inform Oil Sands Process Water Release: A Technical Workshop Summary

“…In addition to focused laboratory work on mammals, an extensive amount of work has been conducted on aquatic organisms in single‐organism tests, in microcosms, and with specific molecular biomarkers (Anderson et al 2011; Gagné et al ; He et al ; Hagen et al ; Sansom et al ; Scarlett et al ; Toor et al ; Wiseman, Anderson et al ; Wiseman, He et al ; Arens et al ; Chen et al ; Islam et al ; Kasiri et al ; Mohseni et al 2015; Zhang et al ). The application of whole effluent regulatory testing in concert with detailed chemical analyses supports characterization of OSPW risks to aquatic ecosystems relative to approved effluent discharges from other regulated industries (Kilgour et al ).…”