title: Assessing accumulation and biliary excretion of naphthenic acids in yellow perch exposed to oil sands-affected waters.
abstract: Naphthenic acids are known to be the most prevalent group of organic compounds in oil sands tailings-associated waters. Yellow perch (Perca flavescens) were exposed for four months to oil sands-influenced waters in two experimental systems located on an oil sands lease 30 km north of Fort McMurray Alberta: the Demonstration Pond, containing oil sands tailings capped with natural surface water, and the South Bison Pond, integrating lean oil sands. Yellow perch were also sampled from three lakes: Mildred Lake that receives water from the Athabasca River, Sucker Lake, at the edge of oil sands extraction activity, and Kimowin Lake, a distant reference site. Naphthenic acids were measured in perch muscle tissue using gas chromatography-mass spectrometry (GC-MS). Bile metabolites were measured by GC-MS techniques and by high performance liquid chromatography (HPLC) with fluorescence detection at phenanthrene wavelengths. A method was developed using liquid chromatography-high resolution mass spectrometry (LC-HRMS) to evaluate naphthenic acids in bile. Tissue analysis did not show a pattern of naphthenic acids accumulation in muscle tissue consistent with known concentrations in exposed waters. Bile fluorescence and LC-HRMS methods were capable of statistically distinguishing samples originating from oil sands-influenced waters versus reference lakes. Although the GC-MS and HPLC fluorescence methods were correlated, there were no significant correlations of these methods and the LC-HRMS method. In yellow perch, naphthenic acids from oil sands sources do not concentrate in tissue at a measurable amount and are excreted through a biliary route. LC-HRMS was shown to be a highly sensitive, selective and promising technique as an indicator of exposure of biota to oil sands-derived naphthenic acids.
authors.affiliation: Canadian Rivers Institute, Department of Biology, University of Prince Edward Island, Canada. Electronic address: Mheuvel@upei.ca.
authors.forename: Michael R
authors.initials: MR
authors.lastname: van den Heuvel
authors.forename: Natacha S
authors.initials: NS
authors.lastname: Hogan
authors.forename: Gillian Z
authors.initials: GZ
authors.lastname: MacDonald
authors.forename: Fabrice
authors.initials: F
authors.lastname: Berrue
authors.forename: Rozlyn F
authors.initials: RF
authors.lastname: Young
authors.forename: Collin J
authors.initials: CJ
authors.lastname: Arens
authors.forename: Russell G
authors.initials: RG
authors.lastname: Kerr
authors.forename: Phillip M
authors.initials: PM
authors.lastname: Fedorak
mesh_terms: D000416:Alberta; D000818:Animals; D002264:Carboxylic Acids / Q000032:analysis / Q000378:metabolism*; D004784:Environmental Monitoring; D007668:Kidney / Q000378:metabolism*; D060106:Lakes / Q000737:chemistry; D061329:Oil and Gas Fields; D010471:Perches / Q000378:metabolism*; D061005:Ponds / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism*
chemical_list: D002264:Carboxylic Acids; D014874:Water Pollutants, Chemical; C046170:naphthenic acid
keywords: Accumulation; Bile metabolite; Excretion; Fish; Naphthenic acids; Oil sands