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Are methylmercury concentrations in the wetlands of Kejimkujik National Park, Nova Scotia, Canada, dependent on geology?

https://arctichealth.org/en/permalink/ahliterature182394
Source
J Environ Qual. 2003 Nov-Dec;32(6):2085-94
Publication Type
Article
Author
Steven D Siciliano
Al Sangster
Chris J Daughney
Lisa Loseto
James J Germida
Andrew N Rencz
Nelson J O'Driscoll
David R S Lean
Author Affiliation
Dep. of Soil Science, Univ. of Saskatchewan, 51 Campus Drive, Saskatoon, SK, Canada S7N 5A8. Siciliano@sask.usask.ca
Source
J Environ Qual. 2003 Nov-Dec;32(6):2085-94
Language
English
Publication Type
Article
Keywords
Animals
Birds - metabolism
Environmental Monitoring - methods
Geologic Sediments - analysis
Humans
Methylmercury compounds - analysis
Nova Scotia
Soil Pollutants - analysis
Water Pollutants, Chemical - analysis
Abstract
In the relatively pristine ecosystem in Kejimkujik Park, Nova Scotia, methylmercury (MeHg) concentrations in loons, Gavia immer, are among the highest recorded anywhere in the world. This study investigated the influence of bedrock lithology on MeHg concentrations in wetlands. Twenty-five different wetland field sites were sampled over four different bedrock lithologies; Kejimkujik monzogranite, black sulfidic slate, gray slate, and greywacke. Soil samples were analyzed for ethylmercury (EtHg), MeHg, total Hg, acid-volatile sulfides (AVS), organic matter, and water content as well as the biological parameters, mercury methyltransferase (HgMT) activity, sulfate reduction rates, fatty acid methyl ester (FAME) composition, and acidity. Methylmercury concentrations in the wetlands were highly dependent (P
PubMed ID
14674530 View in PubMed
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Factors affecting biotic mercury concentrations and biomagnification through lake food webs in the Canadian high Arctic.

https://arctichealth.org/en/permalink/ahliterature263604
Source
Sci Total Environ. 2015 Mar 15;509-510:195-205
Publication Type
Article
Date
Mar-15-2015
Author
Gretchen L Lescord
Karen A Kidd
Jane L Kirk
Nelson J O'Driscoll
Xiaowa Wang
Derek C G Muir
Source
Sci Total Environ. 2015 Mar 15;509-510:195-205
Date
Mar-15-2015
Language
English
Publication Type
Article
Keywords
Animals
Aquatic Organisms - metabolism
Arctic Regions
Canada
Environmental monitoring
Food chain
Lakes
Mercury - metabolism
Water Pollutants, Chemical - metabolism
Abstract
In temperate regions of Canada, mercury (Hg) concentrations in biota and the magnitude of Hg biomagnification through food webs vary between neighboring lakes and are related to water chemistry variables and physical lake features. However, few studies have examined factors affecting the variable Hg concentrations in landlocked Arctic char (Salvelinus alpinus) or the biomagnification of Hg through their food webs. We estimated the food web structure of six high Arctic lakes near Resolute Bay, Nunavut, Canada, using stable carbon (d(13)C) and nitrogen (d(15)N) isotopes and measured Hg (total Hg (THg) in char, the only fish species, and methylmercury (MeHg) in chironomids and zooplankton) concentrations in biota collected in 2010 and 2011. Across lakes, d(13)C showed that benthic carbon (chironomids) was the dominant food source for char. Regression models of log Hg versus d(15)N (of char and benthic invertebrates) showed positive and significant slopes, indicting Hg biomagnification in all lakes, and higher slopes in some lakes than others. However, no principal components (PC) generated using all water chemistry data and physical characteristics of the lakes predicted the different slopes. The PC dominated by aqueous ions was a negative predictor of MeHg concentrations in chironomids, suggesting that water chemistry affects Hg bioavailability and MeHg concentrations in these lower-trophic-level organisms. Furthermore, regression intercepts were predicted by the PCs dominated by catchment area, aqueous ions, and MeHg. Weaker relationships were also found between THg in small char or MeHg in pelagic invertebrates and the PCs dominated by catchment area, and aqueous nitrate and MeHg. Results from these high Arctic lakes suggest that Hg biomagnification differs between systems and that their physical and chemical characteristics affect Hg concentrations in lower-trophic-level biota.
PubMed ID
24909711 View in PubMed
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Marine pollution in fledged Leach's storm-petrels (Hydrobates leucorhous) from Baccalieu Island, Newfoundland and Labrador, Canada.

https://arctichealth.org/en/permalink/ahliterature304156
Source
Mar Pollut Bull. 2021 Jan; 162:111842
Publication Type
Journal Article
Date
Jan-2021
Author
David M Krug
Rhyl Frith
Sarah N P Wong
Robert A Ronconi
Sabina I Wilhelm
Nelson J O'Driscoll
Mark L Mallory
Author Affiliation
Department of Biology, Dalhousie University, 1355 Oxford St., Halifax, Nova Scotia B3H 4R2, Canada.
Source
Mar Pollut Bull. 2021 Jan; 162:111842
Date
Jan-2021
Language
English
Publication Type
Journal Article
Keywords
Animals
Atlantic Ocean
Birds
Canada
Environmental monitoring
Islands
Newfoundland and Labrador
Abstract
The Leach's storm-petrel (Hydrobates leucorhous) is one of the most abundant and widely distributed marine birds in the North Atlantic but is under global population decline, possibly linked to marine pollution. We determined levels of ingested plastic and hepatic total mercury (THg) in recently fledged juveniles that stranded in Newfoundland and Labrador, Canada, and assessed the relationship to body condition, size and diet. Plastic prevalence was high (87.5%) but hepatic THg was relatively low (mean 486.7 ng/g dry weight) compared to other studies. Levels of neither pollutant were significantly related to body metrics of health. Our data confirm that plastic and mercury are pervasive in the western North Atlantic Ocean, prominent even in young birds.
PubMed ID
33203602 View in PubMed
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Mercury bioaccumulation and biomagnification in a small Arctic polynya ecosystem.

https://arctichealth.org/en/permalink/ahliterature263574
Source
Sci Total Environ. 2015 Mar 15;509-510:206-15
Publication Type
Article
Date
Mar-15-2015
Author
Meredith G Clayden
Lilianne M Arsenault
Karen A Kidd
Nelson J O'Driscoll
Mark L Mallory
Source
Sci Total Environ. 2015 Mar 15;509-510:206-15
Date
Mar-15-2015
Language
English
Publication Type
Article
Keywords
Animals
Arctic Regions
Ecosystem
Environmental monitoring
Mercury - metabolism
Water Pollutants, Chemical - metabolism
Zooplankton - metabolism
Abstract
Recurring polynyas are important areas of biological productivity and feeding grounds for seabirds and mammals in the Arctic marine environment. In this study, we examined food web structure (using carbon and nitrogen isotopes, d(13)C and d(15)N) and mercury (Hg) bioaccumulation and biomagnification in a small recurring polynya ecosystem near Nasaruvaalik Island (Nunavut, Canada). Methyl Hg (MeHg) concentrations increased by more than 50-fold from copepods (Calanus hyperboreus) to Arctic terns (Sterna paradisaea), the abundant predators at this site. The biomagnification of MeHg through members of the food web - using the slope of log MeHg versus d(15)N - was 0.157 from copepods (C. hyperboreus) to fish. This slope was higher (0.267) when seabird chicks were included in the analyses. Collectively, our results indicate that MeHg biomagnification is occurring in this small polynya and that its trophic transfer is at the lower end of the range of estimates from other Arctic marine ecosystems. In addition, we measured Hg concentrations in some poorly studied members of Arctic marine food webs [e.g. Arctic alligatorfish (Ulcina olrikii) and jellyfish, Medusozoa], and found that MeHg concentrations in jellyfish were lower than expected given their trophic position. Overall, these findings provide fundamental information about food web structure and mercury contamination in a small Arctic polynya, which will inform future research in such ecosystems and provide a baseline against which to assess changes over time resulting from environmental disturbance.
PubMed ID
25149682 View in PubMed
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Mercury concentrations in feathers of marine birds in Arctic Canada.

https://arctichealth.org/en/permalink/ahliterature264184
Source
Mar Pollut Bull. 2015 Jun 27;
Publication Type
Article
Date
Jun-27-2015
Author
Mark L Mallory
Birgit M Braune
Jennifer F Provencher
D Benjamin Callaghan
H Grant Gilchrist
Samuel T Edmonds
Karel Allard
Nelson J O'Driscoll
Source
Mar Pollut Bull. 2015 Jun 27;
Date
Jun-27-2015
Language
English
Publication Type
Article
Abstract
Mercury (Hg) concentrations are a concern in the Canadian Arctic, because they are relatively high compared to background levels and to similar species farther south, and are increasing in many wildlife species. Among marine birds breeding in the Canadian Arctic, Hg concentrations have been monitored regularly in eggs and intermittently in livers, but feathers have generally not been used as an indicator of Hg exposure or burden. We examined Hg concentrations in six marine bird species in the Canadian Arctic. Ivory gull Pagophila eburnea, feather Hg was exceptionally high, while glaucous gull Larus hyperboreus feather Hg was unexpectedly low, and ratios of feather THg to egg THg varied across species. The proportion of total Hg that was comprised of methyl Hg in ivory gull feathers was lower than in other species, and may be related to photo-demethylation or keratin breakdown in semi-opaque feather tissue.
PubMed ID
26130527 View in PubMed
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Photoreducible mercury loss from Arctic snow is influenced by temperature, and snow age.

https://arctichealth.org/en/permalink/ahliterature266160
Source
Environ Sci Technol. 2015 Sep 15;
Publication Type
Article
Date
Sep-15-2015
Author
Erin Mann
Mark L Mallory
Susan Ziegler
Trevor S Avery
Robert Tordon
Nelson J O'Driscoll
Source
Environ Sci Technol. 2015 Sep 15;
Date
Sep-15-2015
Language
English
Publication Type
Article
Abstract
Mercury (Hg) is an important environmental contaminant, due to its neurotoxicity and ability to bioaccumulate. The Arctic is a mercury-sensitive region, where organisms can accumulate high Hg concentrations. Snowpack mercury photo-redox reactions may control how much Hg is transported with melting Arctic snow. This work aimed to: 1) determine the significance of temperature combined with UV irradiation intensity, and snow age on Hg(0) flux from Arctic snow, and 2) elucidate the effect of temperature on snowpack Hg photoreduction kinetics. Using a Teflon flux chamber, snow temperature, UV irradiation and snow age were found to significantly influence Hg(0) flux from Arctic snow. Cross correlation analysis results suggest that UV radiation has a direct effect on Hg(0)flux, while temperature may indirectly influence flux. Laboratory experiments determined that temperature influenced Hg photoreduction kinetics when snow approached the melting point (>-2 °C), where the pseudo-first order reduction rate constant, k, decreased ~two-fold, and the photoreduced Hg amount, Hg(II)red, increased ten-fold. This suggests that temperature influences Hg photoreduction kinetics indirectly, likely by altering the solid: liquid water ratio. These results imply that large mass transfers of Hg from snow to air may take place during the Arctic snowmelt period, altering photoreducible Hg retention and transport with snow meltwater.
PubMed ID
26371502 View in PubMed
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6 records – page 1 of 1.