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Vasilevich R, Vasilevich M, Lodygin E, Abakumov E. Geochemical Characteristics of the Vertical Distribution of Heavy Metals in the Hummocky Peatlands of the Cryolithozone. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:3847. [PMID: 36900858 PMCID: PMC10001012 DOI: 10.3390/ijerph20053847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 02/17/2023] [Accepted: 02/20/2023] [Indexed: 06/18/2023]
Abstract
One of the main reservoirs depositing various classes of pollutants in high latitude regions are wetland ecosystems. Climate warming trends result in the degradation of permafrost in cryolitic peatlands, which exposes the hydrological network to risks of heavy metal (HM) ingress and its subsequent migration to the Arctic Ocean basin. The objectives included: (1) carrying out a quantitative analysis of the content of HMs and As across the profile of Histosols in background and technogenic landscapes of the Subarctic region, (2) evaluating the contribution of the anthropogenic impact to the accumulation of trace elements in the seasonally thawed layer (STL) of peat deposits, (3) discovering the effect of biogeochemical barriers on the vertical distribution of HMs and As. The analyses of elements were conducted by atom emission spectroscopy with inductively coupled plasma, atomic absorption spectroscopy and scanning electron microscopy with an energy-dispersive X-ray detecting. The study focused on the characteristics of the layer-by-layer accumulation of HMs and As in hummocky peatlands of the extreme northern taiga. It revealed the upper level of microelement accumulation to be associated with the STL as a result of aerogenic pollution. Specifically composed spheroidal microparticles found in the upper layer of peat may serve as indicators of the area polluted by power plants. The accumulation of water-soluble forms of most of the pollutants studied on the upper boundary of the permafrost layer (PL) is explained by the high mobility of elements in an acidic environment. In the STL, humic acids act as a significant sorption geochemical barrier for elements with a high stability constant value. In the PL, the accumulation of pollutants is associated with their sorption on aluminum-iron complexes and interaction with the sulfide barrier. A significant contribution of biogenic element accumulation was shown by statistical analysis.
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Affiliation(s)
- Roman Vasilevich
- Institute of Biology, Komi Science Center, Ural Branch, Russian Academy of Sciences, 167982 Syktyvkar, Russia
| | - Mariya Vasilevich
- Institute of Biology, Komi Science Center, Ural Branch, Russian Academy of Sciences, 167982 Syktyvkar, Russia
| | - Evgeny Lodygin
- Institute of Biology, Komi Science Center, Ural Branch, Russian Academy of Sciences, 167982 Syktyvkar, Russia
| | - Evgeny Abakumov
- Department of Applied Ecology, Faculty of Biology, Saint Petersburg State University, 199178 St. Petersburg, Russia
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Peraza I, Chételat J, Richardson M, Jung TS, Awan M, Baryluk S, Dastoor A, Harrower W, Kukka PM, McClelland C, Mowat G, Pelletier N, Rodford C, Ryjkov A. Diet and landscape characteristics drive spatial patterns of mercury accumulation in a high-latitude terrestrial carnivore. PLoS One 2023; 18:e0285826. [PMID: 37186585 PMCID: PMC10184919 DOI: 10.1371/journal.pone.0285826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 05/02/2023] [Indexed: 05/17/2023] Open
Abstract
Limited information exists on mercury concentrations and environmental drivers of mercury bioaccumulation in high latitude terrestrial carnivores. Spatial patterns of mercury concentrations in wolverine (Gulo gulo, n = 419) were assessed across a 1,600,000 km2 study area in relation to landscape, climate, diet and biological factors in Arctic and boreal biomes of western Canada. Hydrogen stable isotope ratios were measured in wolverine hair from a subset of 80 animals to assess the spatial scale for characterizing environmental conditions of their habitat. Habitat characteristics were determined using GIS methods and raster datasets at two scales, the collection location point and a 150 km radius buffer, which was selected based on results of a correlation analysis between hydrogen stable isotopes in precipitation and wolverine hair. Total mercury concentrations in wolverine muscle ranged >2 orders of magnitude from 0.01 to 5.72 μg/g dry weight and varied geographically, with the highest concentrations in the Northwest Territories followed by Nunavut and Yukon. Regression models at both spatial scales indicated diet (based on nitrogen stable isotope ratios) was the strongest explanatory variable of mercury concentrations in wolverine, with smaller though statistically significant contributions from landscape variables (soil organic carbon, percent cover of wet area, percent cover of perennial snow-ice) and distance to the Arctic Ocean coast. The carbon and nitrogen stable isotope ratios of wolverine muscle suggested greater mercury bioaccumulation could be associated with feeding on marine biota in coastal habitats. Landscape variables identified in the modelling may reflect habitat conditions which support enhanced methylmercury transfer to terrestrial biota. Spatially-explicit estimates of wet atmospheric deposition were positively correlated with wolverine mercury concentrations but this variable was not selected in the final regression models. These landscape patterns provide a basis for further research on underlying processes enhancing methylmercury uptake in high latitude terrestrial food webs.
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Affiliation(s)
- Inés Peraza
- Geography and Environmental Studies, Carleton University, Ottawa, Ontario, Canada
| | - John Chételat
- Environment and Climate Change Canada, National Wildlife Research Centre, Ottawa, Ontario, Canada
| | - Murray Richardson
- Geography and Environmental Studies, Carleton University, Ottawa, Ontario, Canada
| | - Thomas S Jung
- Department of Environment, Government of Yukon, Whitehorse, Yukon, Canada
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
| | - Malik Awan
- Department of Environment, Government of Nunavut, Igloolik, Nunavut, Canada
| | - Steve Baryluk
- Environment and Natural Resources, Government of the Northwest Territories, Inuvik, Northwest Territories, Canada
| | - Ashu Dastoor
- Environment and Climate Change Canada, Air Quality Research Division, Dorval, Quebec, Canada
| | - William Harrower
- Forest and Conservation Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Piia M Kukka
- Department of Environment, Government of Yukon, Whitehorse, Yukon, Canada
| | - Christine McClelland
- Environment and Climate Change Canada, National Wildlife Research Centre, Ottawa, Ontario, Canada
| | - Garth Mowat
- Ministry of Forests, British Columbia Government, Nelson, British Columbia, Canada
- Department of Earth, Environmental and Geographic Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Nicolas Pelletier
- Environment and Climate Change Canada, National Wildlife Research Centre, Ottawa, Ontario, Canada
| | - Christine Rodford
- Environment and Climate Change Canada, National Wildlife Research Centre, Ottawa, Ontario, Canada
| | - Andrei Ryjkov
- Environment and Climate Change Canada, Air Quality Research Division, Dorval, Quebec, Canada
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Assessment of Mercury Concentrations and Fluxes Deposited from the Atmosphere on the Territory of the Yamal-Nenets Autonomous Area. ATMOSPHERE 2021. [DOI: 10.3390/atmos13010037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The problem of mercury input and its further distribution in the Arctic environment is actively debated, especially in recent times, due to the observed processes of permafrost thawing causing the enhanced release of mercury into the Arctic atmosphere and further distribution in the terrestrial and aquatic ecosystem. The atmospheric mercury deposition occurs via dry deposition and wet scavenging by precipitation events. Here we present a study of Hg in wet precipitation on the remote territory of the Russian Arctic; the data were obtained at the monitoring stations Nadym and Salekhard in 2016–2018. Mercury pollution of the Salekhard atmosphere in cold time is mainly determined by regional and local sources, while in Nadym, long-range transport of mercury and local fuel combustion are the main sources of pollutants in the cold season, while internal regional sources have a greater impact on the warm season. Total mercury concentrations in wet precipitation in Nadym varied from <0.5 to 63.3 ng/L. The highest Hg concentrations in the springtime were most likely attributed to atmospheric mercury depletion events (AMDE). The contributions of wet atmospheric precipitation during the AMDE period to the annual Hg deposition were 16.7% and 9.8% in 2016/2017 and 2017/2018, respectively. The average annual volume-weighted Hg concentration (VWC) in the atmospheric precipitation in Nadym is notably higher than the values reported for the remote regions in the Arctic and comparable with the values obtained for the other urbanized regions of the world. Annual Hg fluxes in Nadym are nevertheless close to the average annual fluxes for remote territories of the Arctic zone and significantly lower than the annual fluxes reported for unpolluted sites of continental-scale monitoring networks of the different parts of the world (USA, Europe, and China). The increase of Hg deposition flux with wet precipitation in Nadym in 2018 might be caused by regional emissions of gas and oil combustion, wildfires, and Hg re-emission from soils due to the rising air temperature. The 37 cm increase of the seasonally thawed layer (STL) in 2018 compared to the 10-year average reflects that the climatic changes in the Nadym region might increase Hg(0) evasion, considering a great pool of Hg is contained in permafrost.
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Nozais C, Vincent WF, Belzile C, Gosselin M, Blais MA, Canário J, Archambault P. The Great Whale River ecosystem: ecology of a subarctic river and its receiving waters in coastal Hudson Bay, Canada. ECOSCIENCE 2021. [DOI: 10.1080/11956860.2021.1926137] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Christian Nozais
- Québec-Océan & Département de Biologie, Chimie et Géographie, Université du Québec À Rimouski, Rimouski, Canada
| | - Warwick F. Vincent
- Centre d’études Nordiques (CEN) & Département de Biologie, Université Laval, Québec, Canada
| | - Claude Belzile
- Québec-Océan & Institut des Sciences de la Mer de Rimouski, Université du Québec À Rimouski, Rimouski, Canada
| | - Michel Gosselin
- Québec-Océan & Institut des Sciences de la Mer de Rimouski, Université du Québec À Rimouski, Rimouski, Canada
| | - Marie-Amélie Blais
- Centre d’études Nordiques (CEN) & Département de Biologie, Université Laval, Québec, Canada
| | - João Canário
- Centro de Química Estrututal, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal
| | - Philippe Archambault
- ArcticNet, Québec-Océan & Département de Biologie, Université Laval, Québec, Canada
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Bergin R, Koch I, Rutter A, Shirley J, Zeeb B. Evaluating mercury concentrations in edible plant and fungi species in the Canadian Arctic environment. JOURNAL OF ENVIRONMENTAL QUALITY 2021; 50:877-888. [PMID: 34048608 DOI: 10.1002/jeq2.20253] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 05/18/2021] [Indexed: 06/12/2023]
Abstract
Levels of environmental mercury (Hg) within the Canadian Arctic are a current area of concern. Although efforts have been made to reduce Hg released into the environment, levels remain elevated in flora and fauna. This study examined the concentrations of Hg in soil and naturally occurring edible plant and fungi species, identified by local Inuit residents, from eight locations in Iqaluit, Nunavut, and the surrounding area during the summers of 2018 and 2019. Total Hg concentrations were obtained in 24 soil samples, 112 flora samples from 23 plant and five lichen species, and 157 fungal samples from eight species. Median Hg concentrations in plant species ranged from 0.005 μg g-1 Hg dry weight (dw) in Saxifraga cernua to 0.19 μg g-1 Hg dw in Oxytropis maydelliana. Median concentrations in edible fungi species ranged from 0.084 μg g-1 Hg dw in the Cortinarius croceus (non-puffball species) to 1.6 μg g-1 Hg dw in Lycoperdon perlatum (a puffball mushroom). Additionally, median Hg concentration in puffball species (1.4 μg g-1 ) were higher than non-puffball species (0.12 μg g-1 ). Three puffball species were assessed for methylmercury (MeHg), with mean concentrations ranging from 0.013 to 0.085 μg g-1 MeHg dw. Limited research has been conducted on Hg uptake in naturally occurring edible plant and fungi species of the Canadian Arctic. This study contributes important information on Hg accumulation and processes in edible plant and fungi Arctic species, is the first to focus on plants used by the local Indigenous community, and demonstrates a need for further studies to assess Hg in Arctic environments.
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Affiliation(s)
- Ryan Bergin
- School of Environmental Studies, Bioscience Complex, Queen's Univ., Kingston, ON, K7L 3N6, Canada
| | - Iris Koch
- Dep. of Chemistry and Chemical Engineering, Royal Military College of Canada (RMC), Kingston, ON, K7K 7B4, Canada
| | - Allison Rutter
- School of Environmental Studies, Bioscience Complex, Queen's Univ.s, Kingston, ON, K7L 3N6, Canada
| | - Jamal Shirley
- Nunavut Research Institute, Box 1720, Building 959, Iqaluit, Nunavut, X0A 0H0, Canada
| | - Barbara Zeeb
- Dep. of Chemistry and Chemical Engineering, Royal Military College of Canada, Kingston, ON, K7K 7B4, Canada
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Gopikrishna VG, Kannan VM, Binish MB, Abdul Shukkur M, Krishnan KP, Mohan M. Mercury in the sediments of freshwater lakes in Ny-Ålesund, Arctic. ENVIRONMENTAL MONITORING AND ASSESSMENT 2020; 192:538. [PMID: 32699977 DOI: 10.1007/s10661-020-08511-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 07/19/2020] [Indexed: 06/11/2023]
Abstract
Mercury and its speciation in aquatic ecosystems have been assessed globally. Even though previous studies were limited to Arctic freshwater lakes, they are highly significant in the context of the changing climate. The present study is based on sediment samples collected from three Arctic freshwater lakes over a period of 4 years (2015-2018). The samples were analysed for total mercury (THg), methyl mercury (MHg), and various mercury fractions. The observed mean THg and MHg concentrations were 22.23 ng/g and 0.41 ng/g respectively; these values were comparable with those for other Arctic freshwater lakes. The mercury content significantly varied among the years as well as among the lakes. Changes in snowdrift and meltwater inputs, which are the major sources of water for the lakes, may have influenced the sediment mercury content along with geographical location and increased productivity. The results of MHg indicated the susceptibility of lake sediments to methylation. The major fractions observed were the organo-chelated form of mercury, followed by the elemental and water-soluble forms. These results indicate the availability of mercury for methylation. Hence, it is necessary to conduct more studies on the influence of climate change, mercury release through permafrost melting, and atmospheric deposition.
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Affiliation(s)
- V G Gopikrishna
- School of Environmental Sciences, Mahatma Gandhi University, Kottayam, Kerala, 686560, India
| | - V M Kannan
- School of Environmental Sciences, Mahatma Gandhi University, Kottayam, Kerala, 686560, India
| | - M B Binish
- School of Environmental Sciences, Mahatma Gandhi University, Kottayam, Kerala, 686560, India
| | - M Abdul Shukkur
- School of Environmental Sciences, Mahatma Gandhi University, Kottayam, Kerala, 686560, India
| | - K P Krishnan
- National Centre for Polar and Ocean Research, Vasco da Gama, Goa, 403802, India
| | - Mahesh Mohan
- School of Environmental Sciences, Mahatma Gandhi University, Kottayam, Kerala, 686560, India.
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7
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Tang WL, Liu YR, Guan WY, Zhong H, Qu XM, Zhang T. Understanding mercury methylation in the changing environment: Recent advances in assessing microbial methylators and mercury bioavailability. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 714:136827. [PMID: 32018974 DOI: 10.1016/j.scitotenv.2020.136827] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 01/17/2020] [Accepted: 01/18/2020] [Indexed: 06/10/2023]
Abstract
Methylmercury (MeHg) is a neurotoxin, mainly derived from microbial mercury methylation in natural aquatic environments, and poses threats to human health. Polar regions and paddy soils are potential hotspots of mercury methylation and represent environmental settings that are susceptible to natural and anthropogenic perturbations. The effects of changing environmental conditions on the methylating microorganisms and mercury speciation due to global climate change and farming practices aimed for sustainable agriculture were discussed for polar regions and paddy soils, respectively. To better understand and predict microbial mercury methylation in the changing environment, we synthesized current understanding of how to effectively identify active mercury methylators and assess the bioavailability of different mercury species for methylation. The application of biomarkers based on the hgcAB genes have demonstrated the occurrence of potential mercury methylators, such as sulfate-reducing bacteria, iron-reducing bacteria, methanogen and syntrophs, in a diverse variety of microbial habitats. Advanced techniques, such as enriched stable isotope tracers, whole-cell biosensor and diffusive gradient thin film (DGT) have shown great promises in quantitatively assessing mercury availability to microbial methylators. Improved understanding of the complex structure of microbial communities consisting mercury methylators and non-methylators, chemical speciation of inorganic mercury under geochemically relevant conditions, and the pathway of cellular mercury uptake will undoubtedly facilitate accurate assessment and prediction of in situ microbial mercury methylation.
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Affiliation(s)
- Wen-Li Tang
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Yu-Rong Liu
- Hubei Key Laboratory of Soil Environment and Pollution Remediation, Huazhong Agricultural University, Wuhan 430070, China
| | - Wen-Yu Guan
- College of Environmental Science and Engineering, Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, Nankai University, Tianjin 300350, China
| | - Huan Zhong
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, China; Environmental and Life Science Program (EnLS), Trent University, Peterborough, Ontario K9L 0G2, Canada
| | - Xiao-Min Qu
- College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Tong Zhang
- College of Environmental Science and Engineering, Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, Nankai University, Tianjin 300350, China.
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Sharma Ghimire P, Tripathee L, Zhang Q, Guo J, Ram K, Huang J, Sharma CM, Kang S. Microbial mercury methylation in the cryosphere: Progress and prospects. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 697:134150. [PMID: 32380618 DOI: 10.1016/j.scitotenv.2019.134150] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 08/20/2019] [Accepted: 08/26/2019] [Indexed: 06/11/2023]
Abstract
Mercury (Hg) is one of the most toxic heavy metals, and its cycle is mainly controlled by oxidation-reduction reactions carried out by photochemical or microbial process under suitable conditions. The deposition and accumulation of methylmercury (MeHg) in various ecosystems, including the cryospheric components such as snow, meltwater, glaciers, and ice sheet, and subsequently in the food chain pose serious health concerns for living beings. Unlike the abundance of knowledge about the processes of MeHg production over land and oceans, little is known about the sources and production/degradation rate of MeHg in cryosphere systems. In addition, processes controlling the concentration of Hg and MeHg in the cryosphere remains poorly understood, and filling this scientific gap has been challenging. Therefore, it is essential to study and review the deposition and accumulation by biological, physical, and chemical mechanisms involved in Hg methylation in the cryosphere. This review attempts to address knowledge gaps in understanding processes, especially biotic and abiotic, applicable for Hg methylation in the cryosphere. First, we focus on the variability in Hg concentration and mechanisms of Hg methylation, including physical, chemical, microbial, and biological processes, and transportation in the cryosphere. Then, we elaborate on the mechanism of redox reactions and biotic and abiotic factors controlling Hg methylation and biogeochemistry of Hg in the cryosphere. We also present possible mechanisms of Hg methylation with an emphasis on microbial transformation and molecular function to understand variability in Hg concentration in the cryosphere. Recent advancements in the genetic and physicochemical mechanisms of Hg methylation are also presented. Finally, we summarize and propose a method to study the unsolved issues of Hg methylation in the cryosphere.
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Affiliation(s)
- Prakriti Sharma Ghimire
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Himalayan Environment Research Institute (HERI), Kathmandu, Nepal
| | - Lekhendra Tripathee
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Himalayan Environment Research Institute (HERI), Kathmandu, Nepal.
| | - Qianggong Zhang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100085, China
| | - Junming Guo
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China
| | - Kirpa Ram
- Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi, India
| | - Jie Huang
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100085, China; Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Chhatra Mani Sharma
- Himalayan Environment Research Institute (HERI), Kathmandu, Nepal; Central Department of Environmental Science, Tribhuvan University, Kathmandu, Nepal
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100085, China.
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Du H, Ma M, Igarashi Y, Wang D. Biotic and Abiotic Degradation of Methylmercury in Aquatic Ecosystems: A Review. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2019; 102:605-611. [PMID: 30603765 DOI: 10.1007/s00128-018-2530-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 12/18/2018] [Indexed: 05/16/2023]
Abstract
Mercury (Hg) methylation and demethylation is supposed to simultaneously exist in the environment and form a cycle, which determines the net production of methylmercury (MeHg). Exploring the mechanisms of MeHg formation and degradation, and its final fate in the natural environment is essential to understanding the biogeochemical cycle of Hg. However, MeHg demethylation has been less studied in the past years comparing with Hg methylation, particularly in anaerobic microorganisms whose demethylation role has been under-evaluated. This review described the current state of knowledge on biotic (microorganisms) and abiotic demethylation (photodegradation, chemical degradation) of MeHg. The decomposition of MeHg performed by microorganisms has been identified as two different pathways, reductive demethylation (RD) and oxidative demethylation (OD). Anaerobic and aerobic microorganisms involved in the process of RD and OD, influencing factors as well as research background and histories are systematically described in this review. It is predicted that the photodegradation mechanism, as well as anaerobic microorganisms involved in MeHg formation and degradation cycle will be the focus of future research.
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Affiliation(s)
- Hongxia Du
- College of Resources and Environment, Southwest University, Chongqing, 400715, China
- Chongqing Key Laboratory of Bio-Resource for Bioenergy, Southwest University, Chongqing, 400715, China
| | - Ming Ma
- College of Resources and Environment, Southwest University, Chongqing, 400715, China
| | - Yasuo Igarashi
- College of Resources and Environment, Southwest University, Chongqing, 400715, China.
- Chongqing Key Laboratory of Bio-Resource for Bioenergy, Southwest University, Chongqing, 400715, China.
| | - Dingyong Wang
- College of Resources and Environment, Southwest University, Chongqing, 400715, China.
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Pacyna AD, Frankowski M, Kozioł K, Węgrzyn MH, Wietrzyk-Pełka P, Lehmann-Konera S, Polkowska Ż. Evaluation of the use of reindeer droppings for monitoring essential and non-essential elements in the polar terrestrial environment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 658:1209-1218. [PMID: 30677983 DOI: 10.1016/j.scitotenv.2018.12.232] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 12/09/2018] [Accepted: 12/14/2018] [Indexed: 06/09/2023]
Abstract
Excess or toxic metals, non-metals and metalloids can be eliminated from the organism by deposition in inert tissue (e.g. fur) or excretion with body secretions, urine and faeces. Droppings are one of the main routes for the elimination of multiple elements and they can be collected without direct contact with the animal. Contaminant concentration has been examined in non-lethally collected tissues of several species (especially reptilian, avian and mammalian). However, studies on species residing in polar areas are still limited, especially of mammals from the European Arctic. Reindeers are the only large herbivores living in Svalbard, being an essential part of the Arctic terrestrial ecosystem. Although reindeer presence has a high impact on their surroundings, those huge mammals are rarely part of ecotoxicological studies regarding metal pollution. In this paper, the droppings of Svalbard reindeer were used as a non-invasively collected tissue to examine the excretion pathway of 30 elements. Samples were collected in mesic and moss tundra, representing summer, winter and winter-transitional excretion. For more than a half of the studied elements, significant differences occurred between the samples collected in the two tundra types. The feasibility of older and fresh samples was assessed based on summer droppings, and significant differences were found for K, As, Mn, Na, Ni, and Sb concentrations. No relevant differences in element levels were observed for samples collected from adult females, adult males and calves, except for zinc and potassium. Results show that reindeer droppings are an important vector for the transfer of many metals, non-metals and metalloids including calcium, phosphorus, zinc, aluminium and lead. As a sedentary species, feeding on local food sources, Svalbard reindeer is a valuable indicator of trace element presence in the polar terrestrial ecosystem.
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Affiliation(s)
- Aneta Dorota Pacyna
- Faculty of Chemistry, Department of Analytical Chemistry, Gdansk University of Technology, Narutowicza 11/12, 80-233 Gdansk, Poland.
| | - Marcin Frankowski
- Faculty of Chemistry, Adam Mickiewicz University in Poznan, Umultowska 89b, 61-614 Poznań, Poland
| | - Krystyna Kozioł
- Faculty of Chemistry, Department of Analytical Chemistry, Gdansk University of Technology, Narutowicza 11/12, 80-233 Gdansk, Poland
| | - Michał Hubert Węgrzyn
- Prof. Z. Czeppe Department of Polar Research and Documentation, Institute of Botany, Jagiellonian University, Gronostajowa 3, 30-387 Kraków, Poland
| | - Paulina Wietrzyk-Pełka
- Prof. Z. Czeppe Department of Polar Research and Documentation, Institute of Botany, Jagiellonian University, Gronostajowa 3, 30-387 Kraków, Poland
| | - Sara Lehmann-Konera
- Faculty of Chemistry, Department of Analytical Chemistry, Gdansk University of Technology, Narutowicza 11/12, 80-233 Gdansk, Poland
| | - Żaneta Polkowska
- Faculty of Chemistry, Department of Analytical Chemistry, Gdansk University of Technology, Narutowicza 11/12, 80-233 Gdansk, Poland.
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Janiga M, Haas M. Alpine accentors as monitors of atmospheric long-range lead and mercury pollution in alpine environments. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:2445-2454. [PMID: 30471058 DOI: 10.1007/s11356-018-3742-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 11/12/2018] [Indexed: 06/09/2023]
Abstract
Mercury and lead are deposited in the West Carpathians as long-range transported air pollution. The Alpine accentor (Prunella collaris) was recognized as a cost-effective biomonitor, and used to investigate the bioavailability of contaminants in large alpine areas. The outer tail feathers and blood of the alpine accentors were used for assessment of atmospheric mercury and lead contamination, respectively. Mean mercury levels in feathers of accentors averaged at 1.15 μg/g (SE = 0.105, n = 40). There were no temporal variations in mercury concentrations. Mean blood lead levels were at 5.2 μg/dL (SE = 0.5, n = 27), showing a slight decreasing trend from July to October. Juveniles were not more susceptible to lead accumulation than adults. Bone lead concentrations that increase with age reflect a bioaccumulation effect. A statistically significant negative correlation was found between the length of erythrocytes and the concentration of lead, which may show the first symptoms of microcytosis. In comparison to aquatic ecosystems, the biogeochemical factors that influence methylmercury availability in alpine habitats are not yet completely known and require further investigation. Our findings show that birds in alpine terrestrial ecosystems may contain surprisingly high levels of methylmercury. The mercury levels in the feathers of accentors probably indicate that alpine autotrophs make sufficient amounts of mercury available to the terrestrial food web. The blood lead levels of accentors likely approach the threshold level for further hematological effects. We found a clear tendency in erythrocytes to change their shape from ellipsoid to smaller and rounder with increasing amounts of lead in their blood. The shape of bird erythrocytes appears to be a very sensitive indicator of critical levels of lead in the alpine environment.
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Affiliation(s)
- Marián Janiga
- Institute of High Mountain Biology, Žilina University, Tatranská Javorina, 7, SK-059 56, Slovak Republic
| | - Martina Haas
- Institute of High Mountain Biology, Žilina University, Tatranská Javorina, 7, SK-059 56, Slovak Republic.
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12
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Mann EA, Ziegler SE, Steffen A, O'Driscoll NJ. Increasing chloride concentration causes retention of mercury in melted Arctic snow due to changes in photoreduction kinetics. J Environ Sci (China) 2018; 68:122-129. [PMID: 29908731 DOI: 10.1016/j.jes.2018.01.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 12/19/2017] [Accepted: 01/08/2018] [Indexed: 06/08/2023]
Abstract
Mercury (Hg) in the Arctic is a significant concern due to its bioaccumulative and neurotoxic properties, and the sensitivity of Arctic environments. Previous research has found high levels of Hg in snowpacks with high chloride (Cl-) concentrations. We hypothesised that Cl- would increase Hg retention by decreasing Hg photoreduction to Hg(0) in melted Arctic snow. To test this, changes in Hg photoreduction kinetics in melted Alert, NU snow were quantified with changing Cl- concentration and UV intensity. Snow was collected and melted in Teflon bottles in May 2014, spiked with 0-10μg/g Cl-, and irradiated with 3.52-5.78W·m-2 UV (280-400nm) radiation in a LuzChem photoreactor. Photoreduction rate constants (k) (0.14-0.59hr-1) had positive linear relationships with [Cl-], while photoreduced Hg amounts (Hg(II)red) had negative linear relationships with [Cl-] (1287-64pg in 200g melted snow). Varying UV and [Cl-] both altered Hg(II)red amounts, with more efficient Hg stabilisation by Cl- at higher UV intensity, while k can be predicted by Cl- concentration and/or UV intensity, depending on experimental parameters. Overall, with future projections for greater snowpack Cl- loading, our experimental results suggest that more Hg could be delivered to Arctic aquatic ecosystems by melted snow (smaller Hg(II)red expected), but the Hg in the melted snow that is photoreduced may do so more quickly (larger k expected).
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Affiliation(s)
- E A Mann
- Department of Environmental Science, Acadia University, Wolfville, NS, Canada; Environmental Science Programme, Memorial University of Newfoundland, St. John's, NL, Canada.
| | - S E Ziegler
- Environmental Science Programme, Memorial University of Newfoundland, St. John's, NL, Canada
| | - A Steffen
- Environment and Climate Change Canada, Science and Technology Branch, Air Quality Research Division, Toronto, ON, Canada
| | - N J O'Driscoll
- Department of Environmental Science, Acadia University, Wolfville, NS, Canada
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13
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van den Brink NW, Scheiber IBR, de Jong ME, Braun A, Arini A, Basu N, van den Berg H, Komdeur J, Loonen MJJE. Mercury associated neurochemical response in Arctic barnacle goslings (Branta leucopsis). THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 624:1052-1058. [PMID: 29929222 DOI: 10.1016/j.scitotenv.2017.12.191] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 12/04/2017] [Accepted: 12/17/2017] [Indexed: 06/08/2023]
Affiliation(s)
- Nico W van den Brink
- Wageningen University, Div. Toxicology, Box 8000, 6700 EA Wageningen, The Netherlands.
| | - Isabella B R Scheiber
- University Groningen, Groningen Institute of Evolutionary Life Sciences, Behavioural and Physiological Ecology, PO. Box 11103, 9700 CC Groningen, The Netherlands
| | - Margje E de Jong
- Arctic Centre, University Groningen, P.O. Box 716, 9700 AS Groningen, The Netherlands
| | - Anna Braun
- University Groningen, Groningen Institute of Evolutionary Life Sciences, Behavioural and Physiological Ecology, PO. Box 11103, 9700 CC Groningen, The Netherlands
| | - Adeline Arini
- Faculty of Agricultural and Environmental Sciences, McGill University, 21111 Lakeshore Road, Ste-Anne-de-Bellevue, Quebec H9X 3V9, Canada
| | - Niladri Basu
- Faculty of Agricultural and Environmental Sciences, McGill University, 21111 Lakeshore Road, Ste-Anne-de-Bellevue, Quebec H9X 3V9, Canada
| | - Hans van den Berg
- Wageningen University, Div. Toxicology, Box 8000, 6700 EA Wageningen, The Netherlands
| | - Jan Komdeur
- University Groningen, Groningen Institute of Evolutionary Life Sciences, Behavioural and Physiological Ecology, PO. Box 11103, 9700 CC Groningen, The Netherlands
| | - Maarten J J E Loonen
- Arctic Centre, University Groningen, P.O. Box 716, 9700 AS Groningen, The Netherlands
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14
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Vasilevich MI, Vasilevich RS. Features of Heavy Metal Accumulation by Epiphytic Lichens in Background Areas of the Taiga Zone in the European Northwest of Russia. RUSS J ECOL+ 2018. [DOI: 10.1134/s1067413618010137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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15
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Halbach K, Mikkelsen Ø, Berg T, Steinnes E. The presence of mercury and other trace metals in surface soils in the Norwegian Arctic. CHEMOSPHERE 2017; 188:567-574. [PMID: 28915375 DOI: 10.1016/j.chemosphere.2017.09.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 09/02/2017] [Accepted: 09/04/2017] [Indexed: 06/07/2023]
Abstract
Svalbard is an important study area for investigating the long-range transport of mercury (Hg) and other trace elements to the Arctic. Few studies have focused on their concentrations in Arctic soils. With ongoing climate change leading to thawing permafrost ground the soil compartment is of increasing importance in the Arctic. In this study, elemental composition and soil organic matter (SOM) content of surface and mineral soils in Svalbard are presented. The aim is to provide new data on soils in the Arctic and to gain more knowledge about the role of the soil in the biogeochemical cycle of mercury (Hg). Concentrations are reported for Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, S and Zn. Samples were taken in Adventdalen and in the area near Ny-Ålesund. We obtained a mean Hg concentration of 0.111 ± 0.036 μg/g in surface soils (range 0.041-0.254 μg/g). Hg levels in mineral soils (mean: 0.025 ± 0.013 μg/g; range: 0.004-0.060 μg/g) were substantially lower than in the corresponding surface soils. Hg strongly accumulates in the surface soil layer (upper 3 cm) and is associated with SOM (surface soil: 59 ± 14%). Hg concentrations in the surface soil were slightly lower than those in the humus layer in mainland Norway and were comparable to levels in soils elsewhere in the Arctic. An inverse association of Hg was found with elements attributed to the mineral soil, indicating that Hg is predominantly derived from atmospheric deposition.
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Affiliation(s)
- Katharina Halbach
- Helmholtz-Centre for Environmental Research (UFZ), Department of Analytical Chemistry, 04318 Leipzig, Germany.
| | - Øyvind Mikkelsen
- Norwegian University of Science and Technology, Department of Chemistry, 7491 Trondheim, Norway
| | - Torunn Berg
- Norwegian University of Science and Technology, Department of Chemistry, 7491 Trondheim, Norway
| | - Eiliv Steinnes
- Norwegian University of Science and Technology, Department of Chemistry, 7491 Trondheim, Norway
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16
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Shao JJ, Liu CB, Zhang QH, Fu JJ, Yang RQ, Shi JB, Cai Y, Jiang GB. Characterization and speciation of mercury in mosses and lichens from the high-altitude Tibetan Plateau. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2017; 39:475-482. [PMID: 27142761 DOI: 10.1007/s10653-016-9828-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 04/26/2016] [Indexed: 06/05/2023]
Abstract
The accumulation and species of mercury (Hg) in mosses and lichens collected from high-altitude Tibetan Plateau were studied. The altitudes of the sampling sites spanned from 1983 to 5147 m, and a total of 130 mosses and 52 lichens were analyzed. The total mercury (THg) contents in mosses and lichens were in the ranges of 13.1-273.0 and 20.2-345.9 ng/g, respectively. The average ratios of methylmercury (MeHg) in THg in mosses and lichens were 2.4 % (0.3-11.1 %) and 2.7 % (0.4-9.6 %), respectively, which were higher than those values reported in other regions. The contents of THg in both mosses and lichens were not correlated with the THg in soils (p > 0.05). The lipid contents displayed a significantly positive correlation with concentrations of MeHg in mosses (r = 0.461, p < 0.01, n = 90), but not in lichens. The correlations between Hg contents in mosses and the altitudes, latitudes and longitudes of sampling sites indicated the mountain trapping and spatial deposition of Hg in the Tibetan Plateau.
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Affiliation(s)
- Jun-Juan Shao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Cheng-Bin Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qing-Hua Zhang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Jian-Jie Fu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Rui-Qiang Yang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Jian-Bo Shi
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
- Institute of Environment and Health, Jianghan University, Wuhan, 430056, China.
| | - Yong Cai
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
- Institute of Environment and Health, Jianghan University, Wuhan, 430056, China
| | - Gui-Bin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
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17
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Bargagli R. Moss and lichen biomonitoring of atmospheric mercury: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 572:216-231. [PMID: 27501421 DOI: 10.1016/j.scitotenv.2016.07.202] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 07/28/2016] [Accepted: 07/28/2016] [Indexed: 06/06/2023]
Abstract
Long-range transport and residence time of elemental Hg (Hg°) in air promote global dispersion and deposition in remote ecosystems. Many biotic and abiotic factors contribute to the photoreduction and phytovolatilization of Hg from terrestrial ecosystems, and the assessment of deposition and volatilization fluxes is very challenging. Mosses and lichens are widespread in nature and constitute the dominant vegetation in alpine and polar ecosystems. This review surveys the results of Hg biomonitoring with cryptogams in areas with different Hg sources and deposition processes. Lichen and moss ecophysiology, and factors affecting Hg uptake and bioaccumulation are discussed. Although some laboratory experiments indicate a linear accumulation of Hg in cryptogams exposed to Hg°, without any significant release, in nature the Hg accumulated in cryptogams is in a dynamic equilibrium with Hg in air and decreases when organisms are transplanted to clean environments. Mercury concentrations in mosses and lichens have often been used to estimate concentrations and deposition fluxes of atmospheric Hg; however, Hg° exchanges between cryptogams and air, and the time necessary for mosses and lichens to equilibrate elemental composition with changing atmospheric chemistry, preclude reliable estimates. Biological processes of Hg uptake and exchange with air cannot be reproduced by mechanical collectors, and comparisons between Hg concentrations in biomonitors and those in atmospheric deposition are scarcely reliable. However, the Hg biomonitoring with mosses and lichens is easy and cheap and allows to locate "hot spots" of natural or anthropogenic emissions and to assess spatio-temporal changes in Hg deposition patterns. Climate change is affecting the global Hg cycle through the melting of sea-ice in coastal Polar Regions, and modifying Hg sequestration in mountain ecosystems. Despite limitations, large-scale monitoring of Hg with mosses and lichens may be used as a tool to evaluate the impact of global processes in remote ecosystems.
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Affiliation(s)
- Roberto Bargagli
- Department of Physical, Earth and Environmental Sciences, University of Siena, Via P.A. Mattioli, 4, Siena, Italy
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18
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Lucia M, Strøm H, Bustamante P, Gabrielsen GW. Trace Element Concentrations in Relation to the Trophic Behaviour of Endangered Ivory Gulls (Pagophila eburnea) During Their Stay at a Breeding Site in Svalbard. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2016; 71:518-529. [PMID: 27744522 DOI: 10.1007/s00244-016-0320-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 10/07/2016] [Indexed: 06/06/2023]
Abstract
The ivory gull is a high-Arctic species considered endangered in most parts of its breeding range. Ivory gulls must cope with both the reduction of sea ice cover triggered by climate change and increasing contaminant loads due to changes in global contaminant pathways. The objective of this study was to assess the concentration of 14 essential and nonessential trace elements at four colonies of ivory gulls breeding on Barentsøya, Svalbard, and the relationship between contaminant exposure and the diet of individuals. Contaminants and stable isotopes (δ15N, δ13C) were determined in blood (red blood cells and whole blood), and feathers of ivory gulls collected over several years. The most quantitatively abundant nonessential trace element found in the ivory gull was mercury (Hg). Selenium (Se) was present in substantial surplus compared with Hg, which would imply relative protection against Hg toxic effects but raises concern about Se potential toxicity. Moreover, other elements were detected, such as silver, arsenic, cadmium, and lead, which would warrant monitoring because of the potential additive/synergetic effects of these compounds. This study demonstrated individual differences in trophic behaviour that triggered discrepancies in Hg concentrations, highlighting the potential biomagnifying ability of this metal in the ivory gull's food web. Results highlighted the mixing of birds coming from different geographical areas on Barentsøya.
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Affiliation(s)
- Magali Lucia
- FRAM High North Research Centre for Climate and the Environment, Norwegian Polar Institute, 6606, Langnes, 9296, Tromsø, Norway.
| | - Hallvard Strøm
- FRAM High North Research Centre for Climate and the Environment, Norwegian Polar Institute, 6606, Langnes, 9296, Tromsø, Norway
| | - Paco Bustamante
- Littoral Environnement Et Sociétés (LIENSs), UMR 7266 CNRS-Université de La Rochelle, 2 rue Olympe de Gouges, 17000, La Rochelle, France
| | - Geir W Gabrielsen
- FRAM High North Research Centre for Climate and the Environment, Norwegian Polar Institute, 6606, Langnes, 9296, Tromsø, Norway
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19
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Shao J, Shi J, Duo B, Liu C, Gao Y, Fu J, Yang R, Jiang G. Mercury in alpine fish from four rivers in the Tibetan Plateau. J Environ Sci (China) 2016; 39:22-28. [PMID: 26899640 DOI: 10.1016/j.jes.2015.09.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 09/30/2015] [Accepted: 10/03/2015] [Indexed: 06/05/2023]
Abstract
As a global pollutant, high levels of mercury (Hg) have been found in remote ecosystem due to the long range atmospheric transport. In this study, a total of 60 fish samples were collected from four rivers across the Tibetan Plateau to study the accumulation of Hg in remote and high-altitude aquatic environment. The total Hg (THg) and methylmercury (MeHg) in fish muscles ranged from 11 to 2097 ng/g dry weight (dw) (average: 819 ng/g dw) and from 14 to 1960 ng/g dw (average: 756 ng/g dw), respectively. Significantly positive linear relationships were observed between the THg (r=0.591, p<0.01, n=36) and MeHg concentrations (r=0.473, p<0.01, n=36) with the trophic level of fish from Lhasa River, suggesting trophic transfer and biomagnification of Hg in this aquatic ecosystem. Moreover, the THg levels in fish had significantly positive correlations with the length (r=0.316, p<0.05, n=60) and weight (r=0.271, p<0.05, n=60) of fish. The high levels of Hg were attributed to the slow growth and long lifespan of the fish under this sterile and cold environment. Risk assessment revealed that the consumption of Oxygymnocypris stewartii, Schizothorax macropogon, Schizothorax waltoni, Schizopygopsis younghusbandi and Schizothorax o'connori would lead to a high exposure to MeHg.
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Affiliation(s)
- Junjuan Shao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Jianbo Shi
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Bu Duo
- Science Faculty, Tibet University, Lhasa 850000, China
| | - Chengbin Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yan Gao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Jianjie Fu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Ruiqiang Yang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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20
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Li C, Zhang Q, Kang S, Liu Y, Huang J, Liu X, Guo J, Wang K, Cong Z. Distribution and enrichment of mercury in Tibetan lake waters and their relations with the natural environment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:12490-12500. [PMID: 25903178 DOI: 10.1007/s11356-015-4498-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 04/06/2015] [Indexed: 06/04/2023]
Abstract
Mercury (Hg) in aquatic ecosystems is of great concern due to its toxicity, bioaccumulation, and magnification in the food web. The Tibetan Plateau (TP) is endowed with the highest and largest lakes on earth, whereas Hg distribution and behavior in lake waters are least known. In this study, surface water samples from 38 lakes over the TP were collected and determined for the total Hg (THg) concentrations. Results revealed a wide range of THg concentrations from <1 ng to 40.3 ng L(-1). THg in lake waters exhibited an increasing trend along the southeast to northwest transect over the TP. Strong positive correlations were observed between THg concentrations and salinity and salinity-related environmental variables, especially for total dissolved solids (TDS) and some of the major ions such as Na(+), K(+), and Cl(-), suggesting the enrichment of Hg in saline lakes. The large-scale geographical pattern of climatic and environmental factors shows a decreasing precipitation and an increasing evaporation northwards and westwards and thereby induces gradient-enhanced enrichment of soluble substances in lake waters, which are likely to complex more Hg in northwestern TP. Our study provides the first comprehensive baseline data set of Hg in Tibetan lake waters and highlights the concurrent high Hg and salinity, representing valuable references and fundamental rules in further understanding the behavior and fate of Hg in lakes over the TP and perhaps high-altitude regions beyond.
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Affiliation(s)
- Chengding Li
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
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21
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Evans MS, Muir DCG, Keating J, Wang X. Anadromous char as an alternate food choice to marine animals: a synthesis of Hg concentrations, population features and other influencing factors. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 509-510:175-194. [PMID: 25467220 DOI: 10.1016/j.scitotenv.2014.10.074] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Revised: 10/06/2014] [Accepted: 10/20/2014] [Indexed: 06/04/2023]
Abstract
This study was conducted to confirm sporadic measurements made over the late 1970s to the early 1990 s 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 <0.05 μg/g (wet weight) and, at each location, generally increased with fish length, age and nitrogen isotope (δ(15)N) ratio and decreased with condition factor and %lipid; correlations with carbon isotope (δ(13)C) ratio were inconsistent. Location and year were significant variables influencing Hg concentrations over the study area; longitude and latitude also were significant influencing variables. Char length, weight, age, condition factor and lipid content explained additional variance. A tendency towards higher Hg concentrations with increasing latitude may be partially related to decreasing growth of char towards the north. However, Hg concentrations in char were positively correlated with growth rates suggesting that Hg concentrations in char also were higher in the more productive study areas, including to the west where mainland riverine inputs of terrestrial carbon, nutrients, and Hg were greater. The data base for assessing time trends in char was limited by the small number of years investigated at most locations, variable fish size across years, small sample size, etc. Where temporal trends were detected, they were of increase on the long term (1970s, 1980s or early 1990 s to the present) but of decrease on the short term (early 2000s to present) with Nain (Labrador) showing the converse pattern. Higher Hg concentrations were also related to lower condition factor and cooler springs. Hg concentrations in anadromous char are compared with other terrestrial, aquatic and marine vertebrates in traditional diets. The known information on anadromous char is reviewed including population features, habitat, and harvests. Future Hg trend monitoring should focus on specific locations and harvest areas within these areas to better assess trends and influencing factors.
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Affiliation(s)
- Marlene S Evans
- Environment Canada, Water Science and Technology Directorate, 11 Innovation Blvd., Saskatoon SK S7N 3H5, Canada.
| | - Derek C G Muir
- Environment Canada, Water Science and Technology Directorate, 867 Lakeshore Rd., Burlington, ON L7R 4A6, Canada
| | - Jonathan Keating
- Environment Canada, Water Science and Technology Directorate, 11 Innovation Blvd., Saskatoon SK S7N 3H5, Canada
| | - Xiaowa Wang
- Environment Canada, Water Science and Technology Directorate, 867 Lakeshore Rd., Burlington, ON L7R 4A6, Canada
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22
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Steffen A, Lehnherr I, Cole A, Ariya P, Dastoor A, Durnford D, Kirk J, Pilote M. Atmospheric mercury in the Canadian Arctic. Part I: a review of recent field measurements. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 509-510:3-15. [PMID: 25497576 DOI: 10.1016/j.scitotenv.2014.10.109] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 10/27/2014] [Accepted: 10/31/2014] [Indexed: 06/04/2023]
Abstract
Long-range atmospheric transport and deposition are important sources of mercury (Hg) to Arctic aquatic and terrestrial ecosystems. We review here recent progress made in the study of the transport, transformation, deposition and reemission of atmospheric Hg in the Canadian Arctic, focusing on field measurements (see Dastoor et al., this issue for a review of modeling studies on the same topics). Redox processes control the speciation of atmospheric Hg, and thus impart an important influence on Hg deposition, particularly during atmospheric mercury depletion events (AMDEs). Bromine radicals were identified as the primary oxidant of atmospheric Hg during AMDEs. Since the start of monitoring at Alert (NU) in 1995, the timing of peak AMDE occurrence has shifted to earlier times in the spring (from May to April) in recent years, and while AMDE frequency and GEM concentrations are correlated with local meteorological conditions, the reasons for this timing-shift are not understood. Mercury is subject to various post-depositional processes in snowpacks and a large portion of deposited oxidized Hg can be reemitted following photoreduction; how much Hg is deposited and reemitted depends on geographical location, meteorological, vegetative and sea-ice conditions, as well as snow chemistry. Halide anions in the snow can stabilize Hg, therefore it is expected that a smaller fraction of deposited Hg will be reemitted from coastal snowpacks. Atmospheric gaseous Hg concentrations have decreased in some parts of the Arctic (e.g., Alert) from 2000 to 2009 but at a rate that was less than that at lower latitudes. Despite numerous recent advances, a number of knowledge gaps remain, including uncertainties in the identification of oxidized Hg species in the air (and how this relates to dry vs. wet deposition), physical-chemical processes in air, snow and water-especially over sea ice-and the relationship between these processes and climate change.
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Affiliation(s)
- Alexandra Steffen
- Environment Canada, Air Quality Processes Research, Toronto M3H 5T4, Ontario, Canada.
| | - Igor Lehnherr
- University of Waterloo, Department of Earth and Environmental Sciences, Waterloo N2L 3G1, Ontario, Canada
| | - Amanda Cole
- Environment Canada, Air Quality Processes Research, Toronto M3H 5T4, Ontario, Canada
| | - Parisa Ariya
- McGill University, Department of Chemistry, 801 Sherbrooke St. W., Montreal H3A 2K6, Quebec, Canada; McGill University, Department of Atmospheric and Oceanic Sciences, 801 Sherbrooke St. W., Montreal H3A 2K6, Quebec, Canada
| | - Ashu Dastoor
- Environment Canada, National Prediction Development Division, Dorval H9P 1J3, Quebec, Canada
| | - Dorothy Durnford
- Environment Canada, National Prediction Development Division, Dorval H9P 1J3, Quebec, Canada
| | - Jane Kirk
- Environment Canada, Aquatic Contaminants Research Division, Burlington L7R 4A6, Ontario, Canada
| | - Martin Pilote
- Environment Canada, Aquatic Contaminants Research Division, Montreal H2Y 2E7, Quebec, Canada
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Mann EA, Mallory ML, Ziegler SE, Tordon R, O'Driscoll NJ. Mercury in Arctic snow: quantifying the kinetics of photochemical oxidation and reduction. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 509-510:115-132. [PMID: 25097105 DOI: 10.1016/j.scitotenv.2014.07.056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 06/27/2014] [Accepted: 07/07/2014] [Indexed: 06/03/2023]
Abstract
Controlled experiments were performed with frozen and melted Arctic snow to quantify relationships between mercury photoreaction kinetics, ultra violet (UV) radiation intensity, and snow ion concentrations. Frozen (-10°C) and melted (4°C) snow samples from three Arctic sites were exposed to UV (280-400 nm) radiation (1.26-5.78 W · m(-2)), and a parabolic relationship was found between reduction rate constants in frozen and melted snow with increasing UV intensity. Total photoreduced mercury in frozen and melted snow increased linearly with greater UV intensity. Snow with the highest concentrations of chloride and iron had larger photoreduction and photooxidation rate constants, while also having the lowest Hg(0) production. Our results indicate that the amount of mercury photoreduction (loss from snow) is the highest at high UV radiation intensities, while the fastest rates of mercury photoreduction occurred at both low and high intensities. This suggests that, assuming all else is equal, earlier Arctic snow melt periods (when UV intensities are less intense) may result in less mercury loss to the atmosphere by photoreduction and flux, since less Hg(0) is photoproduced at lower UV intensities, thereby resulting in potentially greater mercury transport to aquatic systems with snowmelt.
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Affiliation(s)
- E A Mann
- Department of Environmental Science, Acadia University, Wolfville, NS, Canada; Environmental Science Programme, Memorial University of Newfoundland, St. John's, NL, Canada
| | - M L Mallory
- Department of Biology, Acadia University, Wolfville, NS, Canada
| | - S E Ziegler
- Environmental Science Programme, Memorial University of Newfoundland, St. John's, NL, Canada
| | - R Tordon
- Environment Canada, Dartmouth, NS, Canada
| | - N J O'Driscoll
- Department of Environmental Science, Acadia University, Wolfville, NS, Canada.
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Øverjordet IB, Gabrielsen GW, Berg T, Ruus A, Evenset A, Borgå K, Christensen G, Lierhagen S, Jenssen BM. Effect of diet, location and sampling year on bioaccumulation of mercury, selenium and cadmium in pelagic feeding seabirds in Svalbard. CHEMOSPHERE 2015; 122:14-22. [PMID: 25441931 DOI: 10.1016/j.chemosphere.2014.10.060] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 10/11/2014] [Accepted: 10/20/2014] [Indexed: 06/04/2023]
Abstract
Hepatic concentrations of mercury (Hg), selenium (Se) and cadmium (Cd) were determined in black-legged kittiwakes (Rissa tridactyla) and little auks (Alle alle) from two fjords in Svalbard (Kongsfjorden; 78°57'N, 12°12'E and Liefdefjorden; 79°37'N, 13°20'E). The inflow of Arctic and Atlantic water differs between the two fjords, potentially affecting element accumulation. Trophic positions (TP) were derived from stable nitrogen isotope ratios (δ(15)N), and stable carbon isotope ratios (δ(13)C) were assessed to evaluate the terrestrial influence on element accumulation. Mercury, Cd, TP and δ(13)C varied significantly between locations and years in both species. Trophic position and feeding habits explained Hg and Cd accumulation in kittiwakes, but not in little auks. Biomagnification of Hg and Cd were found in the food webs of both the Atlantic and the Arctic fjord, and no inter-fjord differences were detected. The δ(13)C were higher in the seabirds from Kongsfjorden than in Liefdefjorden, but this did not explain variations in element accumulation. Selenium concentrations were not influenced by Hg accumulation in kittiwakes, indicating baseline levels of Se in this species. In contrast, correlations between Hg and Se and lower Se:Hg ratios in little auks from Kongsfjorden than in Liefdefjorden indicate a more pronounced influence of Se-Hg complex formation in little auks feeding in Atlantic waters.
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Affiliation(s)
- Ida Beathe Øverjordet
- Norwegian University of Science and Technology (NTNU), Department of Biology, N-7491 Trondheim, Norway.
| | | | - Torunn Berg
- NTNU, Department of Chemistry, N-7491 Trondheim, Norway
| | - Anders Ruus
- Norwegian Institute for Water Research (NIVA), N-0349 Oslo, Norway
| | - Anita Evenset
- Akvaplan-niva, Fram Centre, N-9296 Tromsø, Norway; Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Norway
| | - Katrine Borgå
- Norwegian Institute for Water Research (NIVA), N-0349 Oslo, Norway; Department of Biosciences, University of Oslo, Norway
| | | | | | - Bjørn Munro Jenssen
- Norwegian University of Science and Technology (NTNU), Department of Biology, N-7491 Trondheim, Norway
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25
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Overjordet IB, Kongsrud MB, Gabrielsen GW, Berg T, Ruus A, Evenset A, Borgå K, Christensen G, Jenssen BM. Toxic and essential elements changed in black-legged kittiwakes (Rissa tridactyla) during their stay in an Arctic breeding area. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 502:548-556. [PMID: 25300019 DOI: 10.1016/j.scitotenv.2014.09.058] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2014] [Revised: 09/17/2014] [Accepted: 09/18/2014] [Indexed: 06/04/2023]
Abstract
Seasonal fluctuations in mercury (Hg), cadmium (Cd), zinc (Zn), copper (Cu) and selenium (Se) concentrations were studied in black-legged kittiwakes (Rissa tridactyla) from Kongsfjorden, Svalbard (79°57'N, 12°12'E). Element concentrations were determined in muscle and liver tissue in kittiwakes collected in May, July and October 2007. Stable isotopes of carbon (δ(13)C) and nitrogen (δ(15)N) were analysed in muscle tissue to calculate trophic position (TP) and examine the possible influence of carbon source on element accumulation. Metallothionein (MT) concentrations in liver, as well as Hg and Cd concentration in size-fractionated liver supernatant were determined to evaluate the association between elements and MT. Mercury concentrations declined from May through July to October in both tissues, while concentrations of Cd were similar in May and July and lower in October. A decline in TP between May and July, indicating a shift from fish-based diet towards an invertebrate-based diet explains the declining Hg concentration. The low Hg and Cd concentrations in October may be a result of an increased elimination, probably related to moulting. Selenium decreased in the same manner as Hg in liver and muscle, possibly related to the formation of Se-Hg complexes. Zinc and Cu did not fluctuate in muscle tissue, whereas hepatic Zn concentrations where highest in May. Hepatic Zn concentrations were higher in females compared to males in May, possibly related to egg production. Hepatic MT concentrations were lower in October compared to July, following the same trend as Hg and Cd. Cadmium was predominantly bound to the MT fraction of proteins in liver tissue, whereas Hg was associated with the larger proteins, indicating that MT was not sequestering Hg in the kittiwakes.
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Affiliation(s)
- Ida Beathe Overjordet
- Norwegian University of Science and Technology (NTNU), Department of Biology, N-7491 Trondheim, Norway.
| | - Magnus Brunvoll Kongsrud
- Norwegian University of Science and Technology (NTNU), Department of Biology, N-7491 Trondheim, Norway
| | | | - Torunn Berg
- NTNU, Department of Chemistry, N-7491 Trondheim, Norway
| | - Anders Ruus
- Norwegian Institute for Water Research (NIVA), N-0349 Oslo, Norway
| | - Anita Evenset
- Akvaplan-niva, Fram Centre, N-9296 Tromsø, Norway; Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Norway
| | - Katrine Borgå
- Norwegian Institute for Water Research (NIVA), N-0349 Oslo, Norway; Department of Biosciences, University of Oslo, Norway
| | | | - Bjørn Munro Jenssen
- Norwegian University of Science and Technology (NTNU), Department of Biology, N-7491 Trondheim, Norway
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Overjordet IB, Altin D, Berg T, Jenssen BM, Gabrielsen GW, Hansen BH. Acute and sub-lethal response to mercury in Arctic and boreal calanoid copepods. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2014; 155:160-165. [PMID: 25036619 DOI: 10.1016/j.aquatox.2014.06.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 06/17/2014] [Accepted: 06/25/2014] [Indexed: 06/03/2023]
Abstract
Acute lethal toxicity, expressed as LC50 values, is a widely used parameter in risk assessment of chemicals, and has been proposed as a tool to assess differences in species sensitivities to chemicals between climatic regions. Arctic Calanus glacialis and boreal Calanus finmarchicus were exposed to mercury (Hg(2+)) under natural environmental conditions including sea temperatures of 2° and 10°C, respectively. Acute lethal toxicity (96 h LC50) and sub-lethal molecular response (GST expression; in this article gene expression is used as a synonym of gene transcription, although it is acknowledged that gene expression is also regulated, e.g., at translation and protein stability level) were studied. The acute lethal toxicity was monitored for 96 h using seven different Hg concentrations. The sub-lethal experiment was set up on the basis of nominal LC50 values for each species using concentrations equivalent to 50, 5 and 0.5% of their 96 h LC50 value. No significant differences were found in acute lethal toxicity between the two species. The sub-lethal molecular response revealed large differences both in response time and the fold induction of GST, where the Arctic species responded both faster and with higher mRNA levels of GST after 48 h exposure. Under the natural exposure conditions applied in the present study, the Arctic species C. glacialis may potentially be more susceptible to mercury exposure on the sub-lethal level.
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Affiliation(s)
- Ida Beathe Overjordet
- Norwegian University of Science and Technology, Department of Biology, N-7491 Trondheim, Norway; SINTEF Materials and Chemistry, Environmental Technology, N-7465 Trondheim, Norway.
| | | | - Torunn Berg
- Norwegian University of Science and Technology, Department of Chemistry, N-7491 Trondheim, Norway
| | - Bjørn Munro Jenssen
- Norwegian University of Science and Technology, Department of Biology, N-7491 Trondheim, Norway
| | | | - Bjørn Henrik Hansen
- SINTEF Materials and Chemistry, Environmental Technology, N-7465 Trondheim, Norway
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27
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de Carvalho GGA, Degaspari IAM, Branco V, Canário J, de Amorim AF, Kennedy VH, Ferreira JR. Assessment of total and organic mercury levels in blue sharks (Prionace glauca) from the south and southeastern Brazilian coast. Biol Trace Elem Res 2014; 159:128-34. [PMID: 24801656 DOI: 10.1007/s12011-014-9995-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 04/24/2014] [Indexed: 11/25/2022]
Abstract
Mercury occurrence was evaluated in samples of edible muscle tissue of 27 blue sharks (Prionace glauca) caught in the Atlantic Ocean, adjacent to the south and southeastern Brazilian coast, indicating a slight increase in comparison with previous data obtained for the same studied area and being higher than those fish caught at different sites of the Atlantic Ocean. Total Hg concentrations ranged from 0.46 to 2.40 mg kg(-1) with the organic Hg fraction ranging between 0.44 and 2.37 mg kg(-1). A negative correlation between total Hg concentration in muscle tissue and blue shark size was obtained, and 40% of samples analyzed had Hg concentrations higher than 1.0 mg kg(-1) Hg, the maximum concentration permitted in Brazilian predator fish. Data obtained showed that total Hg can be used as a reliable predictor of organic Hg in blue shark muscle because 95 to 98% of the total Hg measured was found to be organic mercury. The wide range of Hg concentrations obtained for our set of samples can be explained by the heterogeneity of sampled population and the large size of the studied area. Given the adverse toxicological effects of Hg on animals and humans, a regular monitoring program of Hg contamination in Brazilian marine ecosystem can be recommended.
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Affiliation(s)
- Gabriel Gustinelli Arantes de Carvalho
- Laboratório de Química Analítica, Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Avenida Centenário, 303, 13416-000, Piracicaba, SP, Brazil
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28
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Mão de Ferro A, Mota AM, Canário J. Pathways and speciation of mercury in the environmental compartments of Deception Island, Antarctica. CHEMOSPHERE 2014; 95:227-233. [PMID: 24079999 DOI: 10.1016/j.chemosphere.2013.08.081] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 08/28/2013] [Accepted: 08/29/2013] [Indexed: 06/02/2023]
Abstract
This work reports the first integrated mercury study in an Antarctic ecosystem. Sample collection took place in Deception Island, an active volcano in the South Shetland Islands, in several environmental compartments (water, snow, sediments and vegetation) and different locations, during December 2011. The results suggest that volcanic activity is the most important Hg source. Mercury levels in water and sediments sampled at two fumaroles were up to 10,000 times higher than in the other sampling sites. Dissolved methylmercury (MeHg) is below the detection limit in those samples, probably due to the very high temperature found in fumaroles (above 80 °C). On the other hand MeHg accounted for, on average, 23% of total dissolved Hg in the saline waters of Foster bay, which suggests exceptional conditions for Hg methylation. Combined with the high residence time of the water in Foster bay, the results point to the existence of a MeHg pool available for aquatic living organisms.
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Affiliation(s)
- André Mão de Ferro
- CQE, Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1, 1049-001 Lisboa, Portugal
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29
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McCloskey M, Robinson S, Smith PA, Forbes M. Mercury concentration in the eggs of four Canadian Arctic-breeding shorebirds not predicted based on their population statuses. SPRINGERPLUS 2013; 2:567. [PMID: 24255861 PMCID: PMC3825058 DOI: 10.1186/2193-1801-2-567] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 10/18/2013] [Indexed: 11/17/2022]
Abstract
Methylmercury is a toxic form of mercury which persists in food webs for long periods of time and biomagnifies up successive trophic levels. Shorebirds breeding in the Arctic are exposed to methylmercury, derived from both natural and anthropogenic sources, when they ingest their invertebrate prey. Populations of many shorebird species are believed to be declining and one hypothesis for these declines is that they are due to detrimental effects of contaminants, including methylmercury. To test this hypothesis, we assessed mercury contamination in eggs of four Canadian Arctic-breeding shorebird species: black-bellied plover (Pluvialis squatarola), ruddy turnstone (Arenaria interpres), semipalmated plover (Charadrius semipalmatus) and white-rumped sandpiper (Calidris fuscicollis). Black-bellied plovers and ruddy turnstones are declining in the western hemisphere, whereas white-rumped sandpipers and semipalmated plovers have stable or slightly increasing populations. We found no relationship between egg mercury concentration and population trend for these four shorebird species. Intraspecific variation in mercury concentration was high. Notably, the mercury concentrations were much higher than levels found in a previous study of eggs of the same shorebird species from this same site, suggesting that mercury contamination may be subject to substantial inter-annual variation in the Canadian Arctic food web.
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Affiliation(s)
- Meagan McCloskey
- Department of Biology, Carleton University, 1125 Colonel By, Ottawa, ON K1S 5B6 Canada
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30
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Lin Y, Vogt R, Larssen T. Environmental mercury in China: a review. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2012; 31:2431-2444. [PMID: 22887129 DOI: 10.1002/etc.1980] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 06/03/2012] [Accepted: 07/06/2012] [Indexed: 06/01/2023]
Abstract
Mercury is a global pollutant that can be transported over long distances and can bioaccumulate. Currently, China is the country that contributes most to atmospheric Hg emissions and has the greatest intentional (industrial) use of Hg. Mercury in the Chinese environment is generally elevated, particularly in air and water bodies. Remote areas in China also show elevated Hg levels in air and water bodies compared to other rural regions in the world. Large river estuaries are often heavily affected by upstream industrial sources. Mercury is also elevated in sediments, a direct result of contamination in river systems. Regardless of the few heavily polluted sites, the urban environment in Chinese cities is comparable to that of other megacities in terms of Hg pollution, considering the size and rapid development of Chinese cities. Studies on Hg in fish showed generally low levels of contamination resulting from low bioaccumulation of Hg in the mostly short food chains. Mercury in rice has recently received increased research interest; elevated concentrations have been reported from rice grown in contaminated areas and may pose a threat to people dependent on such locally grown food. For the general population, Hg exposure from rice is, however, small. In addition, Hg hair concentration in the Chinese population showed generally low levels of exposure to Hg, except for people with special occupational exposure.
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Affiliation(s)
- Yan Lin
- Norwegian Institute for Water Research, Oslo, Norway.
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31
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Fang SB, Jia XB, Yang XY, Li YD, An SQ. A method of identifying priority spatial patterns for the management of potential ecological risks posed by heavy metals. JOURNAL OF HAZARDOUS MATERIALS 2012; 237-238:290-8. [PMID: 22981743 DOI: 10.1016/j.jhazmat.2012.08.044] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Revised: 08/13/2012] [Accepted: 08/19/2012] [Indexed: 05/07/2023]
Abstract
An approach of identifying priority spatial patterns in response to different ecological risk levels associated with heavy metals (HM) is proposed. First, ecological hotspots (EH) are delineated by integrating NDVI-based assessment with the impact assessment of anthropogenic impact sources. Second, the HM potential ecological risks index (PERI) is calculated and spatially interpolated. Finally, the EH with different PERI values are identified through logic calculation. Study results show that 45.2% of the study region has low HM risks, 53.2% with moderate HM risks, and only 1.6% with high HM risks. In addition, the percentage of EH with low HM risks is 6.5%; the percentage with moderate HM risks is 5.4%; and the percentage with high HM risks is 0.4%. The EH with low and moderate HM ecological risks are proposed to be the regions in priority for management. This approach is potentially useful to HM ecological risk assessment and HM contamination management around the world.
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Affiliation(s)
- S B Fang
- Department of Environmental Science and Engineering, Fudan University, Handan Road 220, Shanghai 200433, China.
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Marusczak N, Larose C, Dommergue A, Yumvihoze E, Lean D, Nedjai R, Ferrari C. Total mercury and methylmercury in high altitude surface snow from the French Alps. THE SCIENCE OF THE TOTAL ENVIRONMENT 2011; 409:3949-3954. [PMID: 21752427 DOI: 10.1016/j.scitotenv.2011.06.040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Revised: 06/11/2011] [Accepted: 06/16/2011] [Indexed: 05/31/2023]
Abstract
Surface snow samples were collected weekly from the 31st of December 2008 to the 21st of June 2009 from Lake Bramant in the French Alps. Total mercury (THg), total dissolved mercury (THgD), methylmercury (MeHg) and particle distributions in surface snow were analyzed. Results showed that THg concentrations, MeHg concentrations and particle load increased with snow surface temperature, which is an indicator of rising temperatures as the season progresses. Significant correlations between MeHg and snow surface temperature and MeHg and total particles greater than 10 μm were observed. This suggests that the MeHg found in the snow originates from atmospheric deposition processes rather than in situ snowpack sources. This study suggests that an important post-winter atmospheric deposition of MeHg and THg occurs on summital zones of the French Alps and it is likely that this contamination originates from the surrounding valleys.
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Affiliation(s)
- Nicolas Marusczak
- Laboratoire de Glaciologie et Géophysique de l'Environnement (LGGE) CNRS UMR 5183, 54, rue Molière, Domaine Universitaire, B.P. 96, 38402 Saint Martin d'Hères, France
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33
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Mann E, Meyer T, Mitchell CPJ, Wania F. Mercury fate in ageing and melting snow: development and testing of a controlled laboratory system. ACTA ACUST UNITED AC 2011; 13:2695-702. [PMID: 21858316 DOI: 10.1039/c1em10297d] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A snow cover can modify when, to what extent, and in what form atmospherically deposited mercury is released to the underlying surface media and/or back to the atmosphere. Investigations of mercury transport and transformation processes in snow packs are hampered by the difficulty in controlling experimental and melt conditions and due to the huge variability in the composition and physical structure of environmental snow packs. A method was developed that allows the detailed mechanistic investigation of mercury fate in snow that is made, aged and melted under controlled laboratory conditions. A number of control samples established that mercury in indoor air, scavenged during the snow making process, constitutes the dominant source of mercury in the artificial snow. No addition of mercury is required. The amount of mercury in fresh snow was quantitatively (102 and 106% in two experiments) recovered in the dissolved and particulate fractions of the melt water and the vessel head space, confirming a mass balance for mercury and the absence of unquantifiable mercury sources and sinks in the experimental system. In snow made from unmodified tap water, more than half of the mercury present in the snowpack was recovered from the bottom of the snow vessel after all of the snow had melted. Such late elution is indicative of mercury being mostly associated with particles that are filtered by, and retained in, the shrinking snowpack. Addition of salt to the snow-making water at an environmentally realistic pH notably shifted the distribution of mercury in the snowpack from the particulate to the dissolved phase, resulting in more than 60% of the mercury eluting in the dissolved phase of early melt water fractions.
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Affiliation(s)
- Erin Mann
- Department of Chemistry, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, Canada
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Schuster RC, Gamberg M, Dickson C, Chan HM. Assessing risk of mercury exposure and nutritional benefits of consumption of caribou (Rangifer tarandus) in the Vuntut Gwitchin First Nation community of Old Crow, Yukon, Canada. ENVIRONMENTAL RESEARCH 2011; 111:881-887. [PMID: 21700277 DOI: 10.1016/j.envres.2011.05.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2010] [Revised: 05/28/2011] [Accepted: 05/29/2011] [Indexed: 05/31/2023]
Abstract
The contamination of traditional foods with chemical pollutants is a challenge to the food security of Aboriginal Peoples. Mercury levels are generally low in terrestrial animals; however renal mercury levels have been shown to change over time in the Porcupine Caribou Herd, the principal food source for the Vuntut Gwitchin First Nation of Old Crow in Yukon, Canada. Seventy-five Porcupine Caribou muscle, sixty-three kidney and three liver samples were analyzed for total mercury. Average concentrations were 0.003, 0.360 and 0.120mg/kg wet weight total mercury for muscle, kidney and liver, respectively. Consumption data of caribou muscle, kidney and liver were collected from twenty-six adults in Vuntut Gwitchin households. Women of child-bearing age (n=5) consumed a median of 71.5g/person/day of caribou muscle and 0.0g/person/day kidney but consumed no liver; median consumptions for all other adults (women aged 40+ and all men, n=21) were 75.8, 3.2 and 2.5g/person/day for meat, kidney and liver, respectively. Median dietary exposures to total mercury from caribou tissues were estimated to be 0.138μg/kg body weight for women of child-bearing age and 0.223μg/kg body weight for other adults. Caribou tissues were found to contribute high levels of important nutrients to the diet and pose minimal health risk from mercury exposure.
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Affiliation(s)
- Roseanne C Schuster
- Health Sciences, University of Northern British Columbia, 3333 University Way, Prince George, BC, Canada
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35
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Jiang S, Liu X, Chen Q. Distribution of total mercury and methylmercury in lake sediments in Arctic Ny-Ålesund. CHEMOSPHERE 2011; 83:1108-1116. [PMID: 21306754 DOI: 10.1016/j.chemosphere.2011.01.031] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Revised: 01/11/2011] [Accepted: 01/14/2011] [Indexed: 05/30/2023]
Abstract
The toxicities and bioavailabilities of total mercury (THg) and methylmercury (MeHg) in aquatic systems have made them the subjects of recent research. In this study, we collected a lake sediment core from Ny-Ålesund in Svalbard and analyzed the distributions of THg and MeHg in the sediments. The increased trend of THg was caused by anthropogenic contamination since the 14th century through long-range transportation, especially after the industrial era. However, the peak values of Hg in surface sediment samples could be explained by the increased algal scavenging process in recent decades. All the biogeochemical proxies (e.g., pigments and diatom biomass) revealed recent sharp increases in aquatic primary production due to the current climate warming. Rock-Eval analyses indicated that algal-derived organic matter took up a large portion, and quantitative calculation showed that 89.6-95.8% of the Hg in post-1950 could be explained by scavenging. The distribution of MeHg has a close relationship with total Hg and organic matter. The oxidation-reduction condition is one of the possible factors affecting the methylation rates in H2 lake sediments. Higher algal productivity and organic matter actually led to the increased trend of methylation in the uppermost sediment. This study supports some new key hypotheses on climate-driven factors affecting Hg and MeHg cycling in High Arctic lake sediments.
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Affiliation(s)
- Shan Jiang
- Institute of Polar Environment, University of Science and Technology of China, Hefei, Anhui 230026, PR China
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36
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Kalisińska E, Budis H, Podlasińska J, Łanocha N, Kavetska KM. Body condition and mercury concentration in apparently healthy Goosander (Mergus merganser) wintering in the Odra estuary, Poland. ECOTOXICOLOGY (LONDON, ENGLAND) 2010; 19:1382-1399. [PMID: 20680455 DOI: 10.1007/s10646-010-0524-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/17/2010] [Indexed: 05/29/2023]
Abstract
Goosanders (Mergus merganser, ad, adult n = 42: M, males 33 and F, females 9; im, immature n = 17: M 8, F 9) were collected in 2005 at wintering site in the River Odra estuary (Poland). The body size (BM, body mass; BL, body length; KL, keel length), weights of organs (LM, liver; KM, kidneys; EM, encephalon), and two condition-related indices (BM/BL and BM/KL) were determined. Based on BM/BL and BM/KL indices, the birds were divided into 3 condition groups: A (very good), B (good), and C (moderate). Total mercury (Hg) concentrations (mg kg(-1) dry weight) were determined in liver, kidney, brain, breast muscle, and bone of 17 birds (ad, n = 8: 8 M, 1 F; im, n = 9: 6 M, 3 F). The highest Hg concentrations (in n = 17) were recorded in liver and kidney (14.7 and 9.9 mg kg(-1), respectively); the concentrations found in muscle and brain were lower (2.3 and 1.3 mg kg(-1), respectively), the lowest concentrations being typical of bone (0.08 mg kg(-1)). Mercury concentrations in the same organs of immature and adult goosanders, as well as males and females, did not differ significantly. On the other hand, distinct differences in Hg concentrations in the organs studied (except for the liver) were observed between individuals assigned to Group A (n = 11) and C (n = 6). Mercury levels were higher in the birds characterised by very good condition, which was most probably related to those birds being more efficient hunters, consuming higher amounts of Hg-containing fish. Significant and negative correlations between the muscle Hg concentration and the two condition-related indices (r > -0.70) were recorded in Group A only: the higher the concentration, the lower the BM/LM and BM/KL values.
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Affiliation(s)
- Elżbieta Kalisińska
- Department of Biology and Medical Parasitology, Pomeranian Medical University, Powstanców Wielkopolskich Av 72, 70-111 Szczecin, Poland.
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Migaszewski ZM, Gałuszka A, Dołegowska S, Crock JG, Lamothe PJ. Mercury in mosses Hylocomium splendens (Hedw.) B.S.G. and Pleurozium schreberi (Brid.) Mitt. from Poland and Alaska: understanding the origin of pollution sources. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2010; 73:1345-1351. [PMID: 20638128 DOI: 10.1016/j.ecoenv.2010.06.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Revised: 06/15/2010] [Accepted: 06/19/2010] [Indexed: 05/29/2023]
Abstract
This report shows baseline concentrations of mercury in the moss species Hylocomium splendens and Pleurozium schreberi from the Kielce area and the remaining Holy Cross Mountains (HCM) region (south-central Poland), and Wrangell-Saint Elias National Park and Preserve (Alaska) and Denali National Park and Preserve (Alaska). Like mosses from many European countries, Polish mosses were distinctly elevated in Hg, bearing a signature of cross-border atmospheric transport combined with local point sources. In contrast, Alaskan mosses showed lower Hg levels, reflecting mostly the underlying geology. Compared to HCM, Alaskan and Kielce mosses exhibited more uneven spatial distribution patterns of Hg. This variation is linked to topography and location of local point sources (Kielce) and underlying geology (Alaska). Both H. splendens and P. schreberi showed similar bioaccumulative capabilities of Hg in all four study areas.
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Affiliation(s)
- Zdzisław M Migaszewski
- Geochemistry and the Environment Division, Institute of Chemistry, Jan Kochanowski University, 15G Swietokrzyska Street, 25-406 Kielce, Poland.
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Choy ES, Gauthier M, Mallory ML, Smol JP, Douglas MSV, Lean D, Blais JM. An isotopic investigation of mercury accumulation in terrestrial food webs adjacent to an Arctic seabird colony. THE SCIENCE OF THE TOTAL ENVIRONMENT 2010; 408:1858-1867. [PMID: 20153017 DOI: 10.1016/j.scitotenv.2010.01.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2009] [Revised: 01/08/2010] [Accepted: 01/08/2010] [Indexed: 05/28/2023]
Abstract
At Cape Vera (Devon Island, Nunavut, Canada), a seabird colony of northern fulmars (Fulmarus glacialis) congregates and releases nutrients through the deposition of guano to the coastal terrestrial environment, thus creating nutrient-fertilized habitats important to insects, birds, and mammals. Here we determined whether mercury was similarly enriched in various terrestrial food web components in this High Arctic coastal ecosystem due to seabird inputs. Stable isotopes (delta(15)N, delta(13)C) were used to identify trophic linkages and possible routes of contaminant transfer in the food web. Values of delta(15)N were significantly higher in lichens and certain plants collected closer to the bird colony, demonstrating a gradient of seabird influence, and were higher at Cape Vera than our reference site at Cape Herschel, on eastern Ellesmere Island, an area relatively unaffected by seabirds. In contrast, delta(13)C showed little variation among terrestrial species, suggesting minimal influence by seabirds. Concentrations of total mercury (THg) in primary producers and phyto/zooplankton were not significantly correlated with distance from the seabird colony or delta(15)N values, and were similar to other taxa from the High Arctic. Our results provide novel data on THg in several Arctic taxa where concentrations have not been reported previously. Moreover, the analyses indicate that delta(15)N is significantly enriched in the adjacent environment by guano fertilization, but our study was unable to show an enrichment of THg and delta(13)C in the terrestrial food web near the seabird colony.
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Affiliation(s)
- Emily S Choy
- Program for Chemical and Environmental Toxicology, Department of Biology, University of Ottawa, Ottawa, ON, Canada.
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Akearok JA, Hebert CE, Braune BM, Mallory ML. Inter- and intraclutch variation in egg mercury levels in marine bird species from the Canadian Arctic. THE SCIENCE OF THE TOTAL ENVIRONMENT 2010; 408:836-840. [PMID: 19962722 DOI: 10.1016/j.scitotenv.2009.11.039] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2009] [Revised: 11/18/2009] [Accepted: 11/18/2009] [Indexed: 05/28/2023]
Abstract
Mercury (Hg) is a toxic metal that has been of increasing concern in the Canadian Arctic. We measured total Hg in eggs of three marine birds (Arctic terns Sterna paradisaea, common eiders Somateria mollissima borealis, long-tailed ducks Clangula hyemalis) that breed in the Canadian Arctic, to compare Hg laying order effects from the same clutch and to examine Hg among species. Early-laid eggs of all three species had 24-48% higher Hg concentrations than late laid eggs. Arctic terns had approximately twice the concentration of Hg in their eggs as the two duck species, and Hg in eider eggs from the High Arctic was higher than Hg in eggs from the Low Arctic. Higher Hg in tern eggs was consistent with this species occupying a higher trophic position in marine food webs, as indicated by stable nitrogen isotope (delta(15)N) values. The egg-laying sequence may need to be considered for Hg biomonitoring studies where small samples sizes are planned, and early eggs may be preferable for such studies since early eggs may be more representative of potential maximum levels of Hg in the marine food webs.
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Affiliation(s)
- Jason A Akearok
- Canadian Wildlife Service, Environment Canada, Iqaluit, NU, Canada X0A 0H0.
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Rigét F, Vorkamp K, Muir D. Temporal trends of contaminants in Arctic char (Salvelinus alpinus) from a small lake, southwest Greenland during a warming climate. ACTA ACUST UNITED AC 2010; 12:2252-8. [DOI: 10.1039/c0em00154f] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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