Distinctive metabolite profiles in in-migrating Sockeye salmon suggest sex-linked endocrine perturbation

Jonathan P. Benskin; Michael G. Ikonomou; Jun Liu, Nik Veldhoen; Cory Dubetz; Caren C. Helbing; John R. Cosgrove;
2014 | Environ. Sci. Technol. | 48 (11670-11678)

The health of Skeena River Sockeye salmon (Onchorhychus nerka) has been of increasing concern due to declining stock returns over the past decade. In the present work, in-migrating Sockeye from the 2008 run were evaluated using a mass spectrometry-based, targeted metabolomics platform. Our objectives were to (a) investigate natural changes in a subset of the hepatic metabolome arising from migration-associated changes in osmoregulation, locomotion, and gametogenesis, and (b) compare the resultant profiles with animals displaying altered hepatic vitellogenin A (vtg) expression at the spawning grounds, which was previously hypothesized as a marker of xenobiotic exposure. Of 203 metabolites monitored, 95 were consistently observed in Sockeye salmon livers and over half of these changed significantly during in-migration. Among the most dramatic changes in both sexes were a decrease in concentrations of taurine (a major organic osmolyte), carnitine (involved in fatty acid transport), and two major polyunsaturated fatty acids (eicosapentaenoic acid and docosahexaenoic acid). In females, an increase in amino acids was attributed to protein catabolism associated with vitellogenesis. Animals with atypical vtg mRNA expression demonstrated unusual hepatic amino acid, fatty acid, taurine, and carnitine profiles. The cause of these molecular perturbations remains unclear, but may include xenobiotic exposure, natural senescence, and/or interindividual variability. These data provide a benchmark for further investigation into the long-term health of migrating Skeena Sockeye.

Assessing Metabolomic Response in Multiple Aquatic Species Exposed to Effluents, Water, and Sediments from Hamilton Harbour, Ontario

Benskin JP, Watson-Leung T, Kleywegt S, Chandramouli B, Tketchva V, Helm P.
2014 | Society of Environmental Toxicology and Chemistry (SETAC)

SETAC NA Conference | September 30, 2022 | Vancouver

Biodegradation potential of aquaculture chemotherapeutants in marine sediments

JP Benskin; MG Ikonomou; BD Surridge; C Dubetz; E Klaassen;
2014 | Aquac. Res.

The commercial chemotherapeutant formulations SLICE® and AlphaMax® [active ingredients emamectin benzoate (EB) and deltamethrin respectively] are used in fin fish aquaculture to control parasitic sea lice. In some regions, the use of these substances has drawn concern from the commercial fishing industry regarding potential adverse effects on non-target organisms. In the present work, biodegradation of EB and deltamethrin, and their commercial formulations, was investigated over 135 days at 4 and 10°C in fresh marine sediments collected from underneath an active open net-pen salmon farm. EB incubated as either pure substance or commercial formulation was recalcitrant at both temperatures under abiotic and biotic conditions. Deltamethrin incubated alone or as its commercial formulation degraded slowly at 10°C (t1/2 = 330 ± 107 and 201 ± 27.1 days respectively). At 4°C, deltamethrin degradation was only significant following incubation as commercial formulation (t1/2 = 285 ±112 days). Degradation rates of EB and deltamethrin as pure substances versus their commercial formulations were not statistically different. Depletion of deltamethrin was observed in 10°C inactive sediments indicating that transformation occurred (at least in part) via an abiotic pathway. Overall, these data provide further insight into the fate and persistence of EB from the ongoing use of SLICE® in British Columbia's salmon aquaculture industry. AlphaMax® is not registered in Canada but is used in other salmon farming countries to control sea lice.

Changes in urine metabolites following a single oral dose of selenomethionine, methylmercury, or their combination in juvenile white sturgeon.

Huang S; Benskin JP; Cosgrove JR; Hung S; Chan L;
2014 | Society of Environmental Toxicology and Chemistry (SETAC)

SETAC NA Conference | September 30, 2022 | Vancouver

Fingerprinting Contaminant Exposure Using Metabolomic Response in Zebrafish Embryos

Chandramouli B; Huang S; Benskin JP; Liu J; Cosgrove J;
2014 | Society of Environmental Toxicology and Chemistry (SETAC)

SETAC NA Conference | September 30, 2022 | Vancouver

Characterizing metabolomic responses of zebrafish following exposure to ethinyl estradiol and Bisphenol A.

Benskin JP; Liu J; Huang SSY; Chan LHM; Cosgrove JR;
2014 | Society of Environmental Toxicology and Chemistry (SETAC)

SETAC Europe | May 1, 2014 | Basel, Switzerland

Variation in systems toxicology

Simmons D; Benskin JP; Martyniuk C; Ekman D; Cosgrove J; Sherry J; Duncker B;
2014 | Society of Environmental Toxicology and Chemistry (SETAC)

SETAC NA Conference | September 30, 2022 | Vancouver

Are perfluoroalkyl acid (PFAA) precursors an important contributor to PFAA concentrations in San Francisco estuary? Occurrence in sediment and effluent.

Benskin JP; Sedlak M; Grace R; Woudneh M; North K; Connor M; Dunlavey E.
2013 | Society of Environmental Toxicology and Chemistry (SETAC)

SETAC NA Conference | November 30, 2022 | Nashville, TN

Quantification of pharmaceuticals, personal care products, and perfluoroalkyl substances in the marine sediments of Puget Sound, Washington, USA

Long, ER; Dutch, M; Weakland, S; Chandramouli, B; Benskin, JP
2013 | Environ. Toxicol. Chem. | 32 (8) (1701-1710)
bioaccumulation , diphenhydramine , exposure , groundwater , perfluorinated compounds , perfluoroalkyl substances , perfluorochemicals , perfluorooctane sulfonate , personal care products , pharmaceuticals , puget sound , quality triad , quantitative-determination , sediments , surface waters

Concentrations of 119 pharmaceuticals and personal care products (PPCPs) and 13 perfluoroalkyl substances (PFASs) in marine sediments measured throughout Puget Sound (n=10) and Bellingham Bay (n=30), Washington, USA, are reported. These data are among the first measurements of PPCPs and PFASs in marine sediments from the Pacific Northwest and provide a comparison to previous measurements of these chemicals in influent, effluent, and biosolids from municipal wastewater treatment plants throughout the region. The concentrations of both PPCPs and PFASs in sediments from Puget Sound and Bellingham Bay ranged from very low to non-detectable for most compounds. Only 14 of the 119 PPCPs and 3 of 13 PFASs were quantifiable in sediments. Diphenhydramine (an antihistamine) was most frequently detected (87.5% of samples), with a maximum concentration of 4.81ng/g dry weight and an estimated mean detected concentration of 1.68ng/g. Triclocarban (an antibacterial) was detected in 35.0% of the samples, with a maximum concentration of 16.6ng/g dry weight. Perfluoroalkyl substances were detected in 2.5% of analyses. Perfluorobutanoate, perfluorooctane sulfonate, and perfluorooctane sulfonamide were detected in 7, 5, and 1 sample(s) each, respectively, with the highest concentrations observed for perfluorooctane sulfonate (1.5ng/g). Detected concentrations were often highest within the industrial harbor in Bellingham Bay and near the cities of Seattle and Bremerton. Environ Toxicol Chem 2013;32:1701-1710. (c) 2013 SETAC

A novel derivatization-based liquid chromatography tandem mass spectrometry method for quantitative characterization of naphthenic acid isomer profiles in environmental waters

Woudneh, MB; Hamilton, MC; Benskin, JP; Wang, GH; McEachern, P; Cosgrove, JR
2013 | J. Chromatogr. A | 1293 (36-43)
biodegradation , derivatization , fingerprinting , lc-ms/ms , mixtures , ms , naphthenic acids , oil sand process water , samples , sands process water , toxicity

A method for quantitative characterization of naphthenic acid (NA) isomer groups by carbon number and extent of cyclization was developed and validated with water samples from northern Alberta. Following solid phase extraction, NAs undergo derivatization with N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide (EDC) allowing detection by positive electrospray ionization tandem mass spectrometry (+ESI)-MS/MS. NA-EDC derivatives produce a common product ion by MS/MS, regardless of structure of the starting NA. Thus, approximately constant relative response factors (RRFs) were assumed for the various isomer groups that elute at a given point in the elution gradient (supported by calculated RRFs for individual model NAs), facilitating quantification using a single standard (1-pyrenebutyric acid). To reduce the impact of major background fatty acids on NA data, the method employed an optimized liquid chromatography method that separated straight chain (Z= 0) analytes from other NAs. Method validation was performed at two spiking levels (7.72 mu g and 38.6 mu g total refined Merichem per 500 mL of reagent water) and good accuracy (mean recoveries of 82.4 +/- 2.5% and 93.0 +/- 2.6%, respectively; range similar to 50-130%) and precision (<17% RSD) were achieved at both spiking levels for all 60 NA isomer groups. The method also performed well in an independent method comparison study in which method accuracy values of 107%, 120%, and 121% were obtained for 2 spiked reagent waters (1 mg/L and 50 mg/L NAs) and spiked Athabasca River water (0.035 mg/L NAs), respectively. Application of the method to samples from northern Alberta revealed that NA concentrations decreased in the order: process water (52.8 mg/L) > tailings pond water (30.6 mg/L) > well water (0.086 mg/L) > surface water (0.007 mg/L), and that samples were distinguishable by NA isomer profile using Principal components analysis. (C) 2013 Elsevier B.V. All rights reserved.

Biodegradation of N-Ethyl Perfluorooctane Sulfonamido Ethanol (EtFOSE) and EtFOSE-Based Phosphate Diester (SAmPAP Diester) in Marine Sediments

Benskin, JP; Ikonomou, MG; Gobas, FAPC; Begley, TH; Woudneh, MB; Cosgrove, JR
2013 | Environ. Sci. Technol. | 47 (3) (1381-1389)
carboxylic-acids , food-web , lake-ontario , liver-microsomes , perfluorinated compounds , perfluoroalkyl contaminants , perfluorochemicals , pfos exposure , precursors , trophic magnification

Investigations into the biodegradation potential of perfluorooctane sulfonate (PFOS)-precursor candidates have focused on low molecular weight substances (e.g., N-ethyl perfluorooctane sulfonamido ethanol (EtFOSE)) in wastewater treatment plant sludge. Few data are available on PFOS-precursor biodegradation in other environmental compartments, and nothing is known about the stability of high-molecular-weight perfluorooctane sulfonamide-based substances such as the EtFOSE-based phosphate diester (SAmPAP diester) in any environmental compartment. In the present work, the biodegradation potential of SAmPAP diester and EtFOSE by bacteria in marine sediments was evaluated over 120 days at 4 and 25 degrees C. At both temperatures, EtFOSE was transformed to a suite of products, including N-ethyl perfluorooctane sulfonamidoacetate, perfluorooctane sulfonamidoacetate, N-ethyl perfluorooctane sulfonamide, perfluorooctane sulfonamide, and perfluorooctane sulfonate. Transformation was significantly more rapid at 25 degrees C (t(1/2) = 44 +/- 3.4 days; error represents standard error of the mean (SEM)) compared to 4 degrees C (t(1/2) = 160 +/- 17 days), but much longer than previous biodegradation studies involving EtFOSE in sludge (t(1/2) similar to 0.7-4.2 days). In contrast, SAmPAP diester was highly recalcitrant to microbial degradation, with negligible loss and/or associated product formation observed after 120 days at both temperatures, and an estimated half-life of >380 days at 25 degrees C (estimated using the lower bounds 95% confidence interval of the slope). We hypothesize that the hydrophobicity of SAmPAP diester reduces its bioavailability, thus limiting biotransformation by bacteria in sediments. The lengthy biodegradation half-life of EtFOSE and recalcitrant nature of SAmPAP diester in part explains the elevated concentrations of PFOS-precursors observed in urban marine sediments from Canada, Japan, and the U.S, over a decade after phase-out of their production and commercial application in these countries.

Analysis, Fate and Disposition of New Poly- and Per-fluorinated Organics in the Environment.

Benskin JP and Müller C
2013 | SETAC Globe | 14

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