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70 records – page 1 of 7.

Activity concentration measurements of selected radionuclides in seals from Canadian Arctic.

https://arctichealth.org/en/permalink/ahliterature279065
Source
J Environ Radioact. 2017 Jan 06;169-170:48-55
Publication Type
Article
Date
Jan-06-2017
Author
Jing Chen
Weihua Zhang
Baki Sadi
Xiaowa Wang
Derek C G Muir
Source
J Environ Radioact. 2017 Jan 06;169-170:48-55
Date
Jan-06-2017
Language
English
Publication Type
Article
Abstract
The activity concentrations of naturally occurring radionuclides (such as (226)Ra, (210)Pb and (210)Po) and long lived (137)Cs were measured in a total of 119 tissue samples (43 blubber, 43 liver, and 33 muscle samples) from 40 ringed seals and 4 bearded seals collected in the Arviat area of Canada during the fall of 2014. Activity concentration of (210)Po was measured in all seal liver and muscle samples individually. The average (210)Po activity concentrations were 25 ± 7.6 Bq/kg fresh weight (fw) in muscle and 211 ± 58 Bq/kg fw in liver for ringed seals, and 20 ± 6.1 Bq/kg fw in muscle and 231 ± 150 Bq/kg fw in liver for bearded seals. Due to insufficient sample material for most samples collected, gamma counting for radioactive caesium and radiochemical analysis for (226)Ra and (210)Pb were performed for pooled samples. Activity concentrations of (210)Pb and (226)Ra were generally below detection limits. While (134)Cs activity concentration was not detectable, (137)Cs activity concentration was detected in muscle and liver samples. On average, the (137)Cs activity concentrations were 0.25 ± 0.05 and 0.12 ± 0.04 Bq/kg fw in muscle and liver samples of ringed seals, and 0.11 ± 0.02 and 0.10 ± 0.03 Bq/kg fw in muscle and liver samples of bearded seals, respectively. Neither (210)Po nor (137)Cs were detected in the blubber samples. This study confirmed that (210)Po is the dominant contributor to radiation doses resulting from seal consumption. Man-made contaminant (137)Cs only contributes less than 0.01% of the total ingestion dose obtained from Arviat seals.
PubMed ID
28068555 View in PubMed
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Anadromous char as an alternate food choice to marine animals: A synthesis of Hg concentrations, population features and other influencing factors.

https://arctichealth.org/en/permalink/ahliterature258432
Source
Sci Total Environ. 2014 Nov 18;
Publication Type
Article
Date
Nov-18-2014
Author
Marlene S Evans
Derek C G Muir
Jonathan Keating
Xiaowa Wang
Author Affiliation
Environment Canada, Water Science and Technology Directorate, 11 Innovation Blvd., Saskatoon SK S7N 3H5, Canada. Electronic address: marlene.evans@ec.gc.ca.
Source
Sci Total Environ. 2014 Nov 18;
Date
Nov-18-2014
Language
English
Publication Type
Article
Abstract
This study was conducted to confirm sporadic measurements made over the late 1970s to the early 1990s which determined that mercury (Hg) concentrations were low in anadromous char across Arctic and subarctic Canada including northern Québec and Labrador. Over 2004-2013, anadromous char populations across northern Canada were investigated at 20 sites for Hg concentrations and life history characteristics. Hg concentrations were extremely low in anadromous char muscle, typically
PubMed ID
25467220 View in PubMed
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An assessment of the toxicological significance of anthropogenic contaminants in Canadian arctic wildlife.

https://arctichealth.org/en/permalink/ahliterature75394
Source
Sci Total Environ. 2005 Dec 1;351-352:57-93
Publication Type
Article
Date
Dec-1-2005
Author
Aaron T Fisk
Cynthia A de Wit
Mark Wayland
Zou Zou Kuzyk
Neil Burgess
Robert Letcher
Birgit Braune
Ross Norstrom
Susan Polischuk Blum
Courtney Sandau
Elisabeth Lie
Hans Jørgen S Larsen
Janneche Utne Skaare
Derek C G Muir
Author Affiliation
Warnell School of Forest Resources, University of Georgia, Athens, GA 30602-2152, USA. afisk@forestry.uga.edu
Source
Sci Total Environ. 2005 Dec 1;351-352:57-93
Date
Dec-1-2005
Language
English
Publication Type
Article
Keywords
Animals
Arctic Regions
Birds
Canada
Environmental monitoring
Environmental Pollutants - analysis - toxicity
Fishes
Hydrocarbons, Chlorinated - analysis - toxicity
Mammals
Metals, Heavy - analysis - toxicity
Abstract
Anthropogenic contaminants have been a concern in the Canadian arctic for over 30 years due to relatively high concentrations of bioaccumulating and biomagnifying organochlorine contaminants (OCs) and toxic metals found in some arctic biota and humans. However, few studies have addressed the potential effects of these contaminants in Canadian arctic wildlife. Prior to 1997, biological effects data were minimal and insufficient at any level of biological organization. The present review summarizes recent studies on biological effects related to contaminant exposure, and compares new tissue concentration data to threshold effects levels. Weak relationships between cadmium, mercury and selenium burdens and health biomarkers in common eider ducks (Somateria mollissima borealis) in Nunavut were found but it was concluded that metals were not influencing the health of these birds. Black guillemots (Cepphus grylle) examined near PCB-contaminated Saglek Bay, Labrador, had enlarged livers, elevated EROD and liver lipid levels and reduced retinol (vitamin A) and retinyl palmitate levels, which correlated to PCB levels in the birds. Circulating levels of thyroid hormones in polar bears (Ursus maritimus) were correlated to PCB and HO-PCB plasma concentrations, but the impact at the population level is unknown. High PCB and organochlorine pesticide concentrations were found to be strongly associated with impaired humoral and cell-mediated immune responses in polar bears, implying an increased infection risk that could impact the population. In beluga whale (Delphinapterus leucas), cytochromes P450 (phase I) and conjugating (phase II) enzymes have been extensively profiled (immunochemically and catalytically) in liver, demonstrating the importance of contaminants in relation to enzyme induction, metabolism and potential contaminant bioactivation and fate. Concentrations of OCs and metals in arctic terrestrial wildlife, fish and seabirds are generally below effects thresholds, with the possible exception of PCBs in burbot (Lota lota) in some Yukon lakes, Greenland shark (Somniosus microcephalus), glaucous and great black-backed gulls (Larus hyperboreus and L. marinus), and TEQs of dioxin-like chemicals in seabird eggs. PCB and DDT concentrations in several arctic marine mammal species exceed effects thresholds, although evidence of stress in these populations is lacking. There is little evidence that contaminants are having widespread effects on the health of Canadian arctic organisms, with the possible exception of polar bears. However, further research and better understanding of organohalogen exposure in arctic biota is needed considering factors such as tissue levels that exceed effects thresholds, exposure to "new" organohalogen contaminants of concern, contaminated regions, and climate change.
PubMed ID
16154621 View in PubMed
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Atmospheric deposition of mercury and methylmercury to landscapes and waterbodies of the Athabasca oil sands region.

https://arctichealth.org/en/permalink/ahliterature257559
Source
Environ Sci Technol. 2014 Jul 1;48(13):7374-83
Publication Type
Article
Date
Jul-1-2014
Author
Jane L Kirk
Derek C G Muir
Amber Gleason
Xiaowa Wang
Greg Lawson
Richard A Frank
Igor Lehnherr
Fred Wrona
Author Affiliation
Aquatic Contaminants Research Division, Environment Canada , Burlington, Ontario L7R 4A6, Canada.
Source
Environ Sci Technol. 2014 Jul 1;48(13):7374-83
Date
Jul-1-2014
Language
English
Publication Type
Article
Keywords
Alberta
Atmosphere - chemistry
Mercury - analysis
Methylmercury compounds - analysis
Oil and Gas Fields
Seasons
Silicon Dioxide - chemistry
Snow
Water Pollutants, Chemical - analysis
Water Pollution - analysis
Abstract
Atmospheric deposition of metals originating from a variety of sources, including bitumen upgrading facilities and blowing dusts from landscape disturbances, is of concern in the Athabasca oil sands region of northern Alberta, Canada. Mercury (Hg) is of particular interest as methylmercury (MeHg), a neurotoxin which bioaccumulates through foodwebs, can reach levels in fish and wildlife that may pose health risks to human consumers. We used spring-time sampling of the accumulated snowpack at sites located varying distances from the major developments to estimate winter 2012 Hg loadings to a ~20 000 km(2) area of the Athabasca oil sands region. Total Hg (THg; all forms of Hg in a sample) loads were predominantly particulate-bound (79 ± 12%) and increased with proximity to major developments, reaching up to 1000 ng m(-2). MeHg loads increased in a similar fashion, reaching up to 19 ng m(-2) and suggesting that oil sands developments are a direct source of MeHg to local landscapes and water bodies. Deposition maps, created by interpolation of measured Hg loads using geostatistical software, demonstrated that deposition resembled a bullseye pattern on the landscape, with areas of maximum THg and MeHg loadings located primarily between the Muskeg and Steepbank rivers. Snowpack concentrations of THg and MeHg were significantly correlated (r = 0.45-0.88, p
PubMed ID
24873895 View in PubMed
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Atmospheric Deposition of Organochlorine Pesticides and Industrial Compounds to Seasonal Surface Snow at Four Glacier Sites on Svalbard, 2013-2014.

https://arctichealth.org/en/permalink/ahliterature305368
Source
Environ Sci Technol. 2020 08 04; 54(15):9265-9273
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
08-04-2020
Author
Mark H Hermanson
Elisabeth Isaksson
Richard Hann
Camilla Teixeira
Derek C G Muir
Author Affiliation
Hermanson & Associates, LLC, 2000 W 53rd Street, Minneapolis, Minnesota 55419, United States.
Source
Environ Sci Technol. 2020 08 04; 54(15):9265-9273
Date
08-04-2020
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Air Pollutants - analysis
Environmental monitoring
Hydrocarbons, Chlorinated - analysis
Ice Cover
Pesticides - analysis
Seasons
Snow
Svalbard
Abstract
Winter snow from four glacial sites on Svalbard was analyzed for atmospheric deposition of 36 organochlorine pesticides (OCPs) and 7 industrial compounds (OCICs) by GC-high-resolution MS. Thirteen of the OCPs and all OCICs were detected at all sites. Sampling sites are 230 km apart from west to east, but are at varying elevations, ranging from 700 to 1202 m a.s.l. Total OCP flux was greater than total OCIC at all sites and was 5 times greater at Lomonosovfonna, and 3 times greater at Austfonna, the most easterly site. Chlorpyrifos dominated OCP flux at Lomonosovfonna (81.7 pg cm-2 yr-1) and Kongsvegen (60.6 pg cm-2 yr-1), and at Austfonna, but not at Holtedahlfonna where dieldrin dominated. trans-chlordane was a major contributor to OCPs. These three pesticides comprised at least 50% of total OCP at each site. OCIC flux was dominated by pentachloroanisole (PCA) at Lomonosovfonna (23.5 pg cm-2 yr-1) and Kongsvegen (14.1 pg cm-2 yr-1). PCA and hexachlorobenzene comprised at least 63% of all OCICs at each site. Air mass frequency from likely source areas showed that Austfonna had the most frequent long-distance air flow, but showed lower amounts of chlorpyrifos and PCA, suggesting local sources of these compounds to other sites.
PubMed ID
32635725 View in PubMed
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Atmospheric deposition of polychlorinated biphenyls to seasonal surface snow at four glacier sites on Svalbard, 2013-2014.

https://arctichealth.org/en/permalink/ahliterature308001
Source
Chemosphere. 2020 Mar; 243:125324
Publication Type
Journal Article
Date
Mar-2020
Author
Mark H Hermanson
Elisabeth Isaksson
Dmitry Divine
Camilla Teixeira
Derek C G Muir
Author Affiliation
Hermanson & Associates LLC, 2000 W 53rd St., Minneapolis, MN, 55419, USA. Electronic address: markhermanson@me.com.
Source
Chemosphere. 2020 Mar; 243:125324
Date
Mar-2020
Language
English
Publication Type
Journal Article
Keywords
Air Pollutants - chemistry
Arctic Regions
Environmental monitoring
Europe
Ice Cover
Incineration
Polychlorinated biphenyls - analysis
Russia
Seasons
Snow - chemistry
Svalbard
Abstract
During spring 2014 we collected annual surface snow from four glacial sites on Svalbard, an archipelago in the European Arctic. The sampling sites are 230?km apart from west to east, but are at varying elevations, affecting local atmospheric contaminant inputs. Samples were analyzed for 209 polychlorinated biphenyl (PCB) congeners. The western sites, Holtedahlfonna and Kongsvegen, had the highest ?PCB flux (26.7?pg?cm-2 yr-1 at Kongsvegen) while the lowest was at Lomonosovfonna, in central Svalbard (14.4?pg?cm-2 yr-1). The greatest difference between sites was the trichlorobiphenyl homologue which was nearly four times greater at Kongsvegen than the eastern site at Austfonna. The most concentrated congeners at each site were PCB-52, 70 + 74, 95, 101, 110 comprising 32-39% of ?PCB, similar to Clophen 40 which is comprised 27% of these congeners. Similar variance of these congeners in samples and Clophen 40 was verified by principal components analysis. Air mass back trajectories from likely source areas for all sites were similar, indicating no difference in frequency or distribution of PCB from long-distances, suggesting local PCB sources contributing to Kongsvegen. We found 2,3-DiCB (PCB-5) and 3,3'-DiCB (PCB-11) at all sites; neither was found in western commercial PCB mixtures. PCB-5 may be from the Russian PCB product "Trichlorobiphenyl" or is residue from production of pigment violet 23. PCB-11 may come from waste incineration in northern Europe containing various pigments. These results, in comparison to earlier data from Lomonosovfonna, suggest that PCB inputs are variable and are not declining over time.
PubMed ID
31765903 View in PubMed
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Bioaccumulation of PCBs in Arctic seabirds: influence of dietary exposure and congener biotransformation.

https://arctichealth.org/en/permalink/ahliterature4749
Source
Environ Pollut. 2005 Apr;134(3):397-409
Publication Type
Article
Date
Apr-2005
Author
Katrine Borgå
Hans Wolkers
Janneche U Skaare
Haakon Hop
Derek C G Muir
Geir W Gabrielsen
Author Affiliation
Norwegian Polar Institute, N-9296 Tromsø, Norway. katrine.borga@npolar.no
Source
Environ Pollut. 2005 Apr;134(3):397-409
Date
Apr-2005
Language
English
Publication Type
Article
Keywords
Aging
Animals
Arctic Regions
Biotransformation
Birds - metabolism
Cytochrome P-450 Enzyme System - metabolism
Diet
Environmental Pollutants - pharmacokinetics
Female
Fishes
Male
Phylogeny
Polychlorinated Biphenyls - pharmacokinetics
Research Support, Non-U.S. Gov't
Seawater
Sex Factors
Zooplankton
Abstract
Four seabird species and their prey (zooplankton or fish) were collected in the Barents Sea to determine how dietary exposure, cytochrome P450 (CYP) enzyme activities and sex influenced their hepatic PCB concentrations and accumulation patterns. Five males and five females from each seabird species (little auk (Alle alle), Brunnich's guillemot (Uria lomvia), black guillemot (Cepphus grylle) and black-legged kittiwake (Rissa tridactyla)) were analysed. PCB concentrations could not be explained directly by carbon source (delta13C) or trophic position (delta15N), but by a combination of dietary parameters (delta13C, delta15N, migratory pattern, age) and contaminant metabolism. Contrary to previous studies, the PCB pattern differed among seabirds, with a higher proportion of persistent congeners (% of PCB-153, RPCB-153) in black-legged kittiwake than in auks. The PCB pattern also differed among auks, with little auk as the most efficient biotransformer (highest RPCB-153 values of persistent congeners). Based on high RPCB-153 values, Brunnich's guillemot poorly metabolised ortho-meta-unsubstituted congeners, whereas black guillemot poorly metabolised meta-para unsubstituted congeners. Species-specific differences in PCB biotransformation were confirmed by metabolic indices, where PCB patterns in seabirds were adjusted for PCB pattern in prey. The relative contribution of ortho-meta-unsubstituted congeners to SigmaPCBs decreased with increasing EROD activity. There were no differences in PCB concentrations, PCB patterns or cytochrome P450 enzyme activities between males and females. CYP P450 activities (CYP1A- and CYP2B/3A-like: EROD and testosterone 6beta-hydroxylation, respectively) were low and did not correlate with concentrations of non- or mono-ortho Cl-substituted PCBs (NO- and MO-PCBs), or with total toxic equivalent concentrations (TEQs) for dioxin-like effects of NO- and MO-PCBs.
PubMed ID
15620585 View in PubMed
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Biological and chemical factors of importance in the bioaccumulation and trophic transfer of persistent organochlorine contaminants in Arctic marine food webs.

https://arctichealth.org/en/permalink/ahliterature4755
Source
Environ Toxicol Chem. 2004 Oct;23(10):2367-85
Publication Type
Article
Date
Oct-2004
  1 website  
Author
Katrine Borgå
Aaron T Fisk
Paul E Hoekstra
Derek C G Muir
Author Affiliation
Norwegian Polar Institute, Polar Environmental Centre, N-9296 Tromsø, Norway.
Source
Environ Toxicol Chem. 2004 Oct;23(10):2367-85
Date
Oct-2004
Language
English
Publication Type
Article
Keywords
Age Factors
Animals
Arctic Regions
Diet
Environmental Pollutants - analysis - pharmacokinetics
Food chain
Humans
Lindane - analysis - pharmacokinetics
Lipids - chemistry
Organic Chemicals
Reproduction
Research Support, Non-U.S. Gov't
Seasons
Tissue Distribution
Abstract
Recent studies of arctic marine food webs have provided detailed insights regarding the biological and chemical factors that influence the bioaccumulation and trophic transfer of persistent organochlorine (OC) contaminants in aquatic systems. The present paper summarizes the recent literature with an emphasis on identifying important ecological factors for explaining variability of OC concentrations among organisms. The Arctic ecosystem has a number of unique attributes, including long food chains, reduced diversity of species, similar food webs across the entire region, and limited influence from pollution point sources. Lipid content, body size, age, gender, reproduction, habitat use, migration, biotransformation, seasonal changes in habitat conditions, feeding ecology, and trophic position have all been demonstrated to influence OC concentrations and bioaccumulation in arctic marine biota. The relative importance of each factor varies among OCs and organisms. Diet or trophic level is the dominant factor influencing OC concentrations and dynamics in seabirds and marine mammals, although biotransformation can significantly influence nonrecalcitrant OCs, such as hexachlorocyclohexane isomers. Dietary accumulation of OCs is also an important route of exposure for arctic fish and zooplankton, and biomagnification of OCs may also occur among these organisms. To date, only limited attempts have been made to model trophic transfer of OCs in the arctic marine food web. Although models developed to assess OC dynamics in aquatic food webs have included some biological variables (e.g., lipid content, feeding rate, diet composition, and growth rate), selection of processes included in these models as well as their mathematical solutions and parameterization all introduce simplification. This reduces biological validity of the models and may be particularly problematic in a highly seasonal environment, such as the Arctic Ocean.
PubMed ID
15511099 View in PubMed
Online Resources
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Biological monitoring of polyfluoroalkyl substances: A review.

https://arctichealth.org/en/permalink/ahliterature168739
Source
Environ Sci Technol. 2006 Jun 1;40(11):3463-73
Publication Type
Article
Date
Jun-1-2006
Author
Magali Houde
Jonathan W Martin
Robert J Letcher
Keith R Solomon
Derek C G Muir
Author Affiliation
Department of Environmental Biology, University of Guelph, Guelph, Ontario, N1G 2W1, Canada.
Source
Environ Sci Technol. 2006 Jun 1;40(11):3463-73
Date
Jun-1-2006
Language
English
Publication Type
Article
Keywords
Alkanesulfonic Acids - analysis
Animals
Ecosystem
Environmental Monitoring - methods - statistics & numerical data
Environmental Pollutants - analysis
Fluorocarbons - analysis
Humans
Hydrocarbons, Fluorinated - analysis - standards
Water Pollutants, Chemical - analysis
Abstract
Polyfluoroalkyl substances (PFSs) are used in industrial and commercial products and can degrade to persistent perfluorocarboxylates (PFCAs) and perfluoroalkyl sulfonates (PFSAs). Temporal trend studies using human, fish, bird, and marine mammal samples indicate that exposure to PFSs has increased significantly over the past 15-25 years. This review summarizes the biological monitoring of PFCAs, PFSAs, and related PFSs in wildlife and humans, compares concentrations and contamination profiles among species and locations, evaluatesthe bioaccumulation/biomagnification in the environment, discusses possible sources, and identifies knowledge gaps. PFSs can reach elevated concentrations in humans and wildlife inhabiting industrialized areas of North America, Europe, and Asia (2-30,000 ng/ mL or ng/g of wet weight (ww)). PFSs have also been detected in organisms from the Arctic and mid-ocean islands (
PubMed ID
16786681 View in PubMed
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Brominated flame retardants in polar bears (Ursus maritimus) from Alaska, the Canadian Arctic, East Greenland, and Svalbard.

https://arctichealth.org/en/permalink/ahliterature6593
Source
Environ Sci Technol. 2006 Jan 15;40(2):449-55
Publication Type
Article
Date
Jan-15-2006
Author
Derek C G Muir
Sean Backus
Andrew E Derocher
Rune Dietz
Thomas J Evans
Geir W Gabrielsen
John Nagy
Ross J Norstrom
Christian Sonne
Ian Stirling
Mitch K Taylor
Robert J Letcher
Author Affiliation
National Water Research Institute, Environment Canada, Burlington, Ontario, Canada. derek.muir@cciw.ca
Source
Environ Sci Technol. 2006 Jan 15;40(2):449-55
Date
Jan-15-2006
Language
English
Publication Type
Article
Abstract
Polybrominated diphenyl ethers (PBDEs) were determined in adipose tissue of adult and subadult female polar bears sampled between 1999 and 2002 from sub-populations in Arctic Canada, eastern Greenland, and Svalbard, and in males and females collected from 1994 to 2002 in northwestern Alaska. Only 4 congeners (BDE47, 99, 100, and 153) were consistently identified in all samples. BDE47 was the major PBDE congener representing from 65% to 82% of the sum (sigma) PBDEs. Age was not a significant covariate for individual PBDEs or sigmaPBDE. Higher proportions of BDE 99, 100, and 153 were generally found in samples from the Canadian Arctic than from Svalbard or the Bering-Chukchi Sea area of Alaska. Geometric mean sigmaPBDE concentrations were highest for female polar bear fat samples collected from Svalbard (50 ng/g lipid weight (lw)) and East Greenland (70 ng/g lw). Significantly lower sigmaPBDE concentrations were found in fat of bears from Canada and Alaska (means ranging from 7.6 to 22 ng/g lw).
PubMed ID
16468388 View in PubMed
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70 records – page 1 of 7.