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Constantino WD, Viana LMDS, Luze FHR, Tostes ECL, Pestana IA, de Carvalho CEV. Mercury levels in an environmentally protected estuarine area in Northeast Brazil: partitioning in the water column and transport to the ocean. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:31383-31394. [PMID: 36447105 DOI: 10.1007/s11356-022-24400-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: 07/27/2022] [Accepted: 11/21/2022] [Indexed: 06/16/2023]
Abstract
In this study, total Hg concentrations (HgT) were determined in the suspended particulate matter (SPM) and the dissolved fraction of the water column to evaluate their behavior through a gradient of physical-chemical parameters in a continuum between rivers and the Serinhaém River estuary of the Pratigi Environmental Protection Area, a pristine environment without point sources of Hg contamination, located in Northeast Brazil. Twelve points were sampled, forming a river-estuary transect, and two samplings were carried out (April and September 2019). Significant spatial and temporal effects were detected only for particulate HgT and not for dissolved HgT. Considering both samplings, the mean HgT concentrations in SPM were 1112 ± 824 and 44 ± 33 ng·g-1 in the river and estuary, respectively. Also, HgT concentrations in the dissolved fraction (1.61 ± 0.61 ng·L-1) were below the limits established by environmental agencies (CONAMA = 2 μg∙L-1 and USEPA = 1.4 μg·L-1). Salinity and SPM concentrations were important predictors of HgT in the water column (R2 = 0.81, p < 0.0001; R2 = 0.56, p < 0.0001, respectively). Mercury transport to the ocean through SPM was 2 kg∙year-1, 4000 times greater than the dissolved fraction.
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Affiliation(s)
- Wendel Dias Constantino
- Laboratório de Ciências Ambientais, Centro de Biociências E Biotecnologia, Universidade Estadual Do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego - 2000 - Parque Califórnia - CEP 28013-602, Campos Dos Goytacazes, Rio de Janeiro, Brazil.
| | - Luísa Maria de Souza Viana
- Laboratório de Ciências Ambientais, Centro de Biociências E Biotecnologia, Universidade Estadual Do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego - 2000 - Parque Califórnia - CEP 28013-602, Campos Dos Goytacazes, Rio de Janeiro, Brazil
| | - Felipe Henrique Rossi Luze
- Laboratório de Ciências Ambientais, Centro de Biociências E Biotecnologia, Universidade Estadual Do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego - 2000 - Parque Califórnia - CEP 28013-602, Campos Dos Goytacazes, Rio de Janeiro, Brazil
| | - Eloá Corrêa Lessa Tostes
- Laboratório de Ciências Ambientais, Centro de Biociências E Biotecnologia, Universidade Estadual Do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego - 2000 - Parque Califórnia - CEP 28013-602, Campos Dos Goytacazes, Rio de Janeiro, Brazil
| | - Inácio Abreu Pestana
- Laboratório de Ciências Ambientais, Centro de Biociências E Biotecnologia, Universidade Estadual Do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego - 2000 - Parque Califórnia - CEP 28013-602, Campos Dos Goytacazes, Rio de Janeiro, Brazil
| | - Carlos Eduardo Veiga de Carvalho
- Laboratório de Ciências Ambientais, Centro de Biociências E Biotecnologia, Universidade Estadual Do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego - 2000 - Parque Califórnia - CEP 28013-602, Campos Dos Goytacazes, Rio de Janeiro, Brazil
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2
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Campeau A, Eklöf K, Soerensen AL, Åkerblom S, Yuan S, Hintelmann H, Bieroza M, Köhler S, Zdanowicz C. Sources of riverine mercury across the Mackenzie River Basin; inferences from a combined HgC isotopes and optical properties approach. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150808. [PMID: 34637879 DOI: 10.1016/j.scitotenv.2021.150808] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 09/30/2021] [Accepted: 10/01/2021] [Indexed: 06/13/2023]
Abstract
The Arctic environment harbors a complex mosaic of mercury (Hg) and carbon (C) reservoirs, some of which are rapidly destabilizing in response to climate warming. The sources of riverine Hg across the Mackenzie River basin (MRB) are uncertain, which leads to a poor understanding of potential future release. Measurements of dissolved and particulate mercury (DHg, PHg) and carbon (DOC, POC) concentration were performed, along with analyses of Hg stable isotope ratios (incl. ∆199Hg, δ202Hg), radiocarbon content (∆14C) and optical properties of DOC of river water. Isotopic ratios of Hg revealed a closer association to terrestrial Hg reservoirs for the particulate fraction, while the dissolved fraction was more closely associated with atmospheric deposition sources of shorter turnover time. There was a positive correlation between the ∆14C-OC and riverine Hg concentration for both particulate and dissolved fractions, indicating that waters transporting older-OC (14C-depleted) also contained higher levels of Hg. In the dissolved fraction, older DOC was also associated with higher molecular weight, aromaticity and humic content, which are likely associated with higher Hg-binding potential. Riverine PHg concentration increased with turbidity and SO4 concentration. There were large contrasts in Hg concentration and OC age and quality among the mountain and lowland sectors of the MRB, which likely reflect the spatial distribution of various terrestrial Hg and OC reservoirs, including weathering of sulfate minerals, erosion and extraction of coal deposits, thawing permafrost, forest fires, peatlands, and forests. Results revealed major differences in the sources of particulate and dissolved riverine Hg, but nonetheless a common positive association with older riverine OC. These findings reveal that a complex mixture of Hg sources, supplied across the MRB, will contribute to future trends in Hg export to the Arctic Ocean under rapid environmental changes.
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Affiliation(s)
- Audrey Campeau
- Department of Earth Sciences, Uppsala University, Sweden; Depatment of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden.
| | - Karin Eklöf
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Anne L Soerensen
- Department of Environmental Research and Monitoring, Swedish Museum of Natural History, Sweden
| | - Staffan Åkerblom
- Statistiska centralbyrån (SCB), Statistic Sweden, Stockholm, Sweden
| | - Shengliu Yuan
- Water Quality Center, Trent University, Peterborough, Ontario, Canada
| | - Holger Hintelmann
- Water Quality Center, Trent University, Peterborough, Ontario, Canada
| | - Magdalena Bieroza
- Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Stephan Köhler
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden
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3
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Amiri V, Li P, Bhattacharya P, Nakhaei M. Mercury pollution in the coastal Urmia aquifer in northwestern Iran: potential sources, mobility, and toxicity. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:17546-17562. [PMID: 33398765 DOI: 10.1007/s11356-020-11865-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 11/29/2020] [Indexed: 06/12/2023]
Abstract
The concentration of total dissolved mercury (HgT) in surface and groundwater resources in the coastal parts of Urmia aquifer (NW of Iran) was investigated to identify the possible sources and sinks of mercury and the geochemical mechanisms controlling its mobilization. The distribution of water samples on the Piper diagram demonstrates that most samples have the Ca-Mg-HCO3 facies. From 62 water samples collected in this area, one sample contained HgT concentrations exceeding the maximum contaminant level recommended by the WHO (6 μg/L). The principal component analysis (PCA) produced five principal components. The positive moderate correlation of HgT with EC, Cl, K, Mg, and Na indicated that the weathering of geological formations was one of the main sources of mercury in groundwater samples. Position of water samples in Eh-pH regions where microorganisms involved in mercury methylation and mineralization were potentially active demonstrated that the aquifer had undergone sulfate reduction and had reached the final stage of the terminal electron accepting process (TEAP) sequence in the methane production processes which are limited to only 37% of the water samples that have anaerobic conditions. Some Hg-bearing species are in nonequilibrium geochemical conditions. The supersaturation of water samples with magnetite and goethite indicated that these Fe-bearing minerals could act as the strong reducing agents for the reduction of Hg(II) to Hg(0).
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Affiliation(s)
- Vahab Amiri
- Department of Geology, Faculty of Science, Yazd University, Yazd, Iran.
| | - Peiyue Li
- School of Water and Environment, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, China
- Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of the Ministry of Education, Chang'an University, No. 126 Yanta Road, Xi'an, 710054, China
| | - Prosun Bhattacharya
- KTH-International Groundwater Arsenic Research Group, Department of Sustainable Development, Environmental Science and Engineering, KTH Royal Institute of Technology, Teknikringen 10B, SE-10044, Stockholm, Sweden
- KWR Water Cycle Research Institute, Groningenhaven 7, 3433 PE, Nieuwegein, The Netherlands
| | - Mohammad Nakhaei
- Department of Applied Geology, Faculty of Earth Science, Kharazmi University, Tehran, Iran
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4
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Kim J, Soerensen AL, Kim MS, Eom S, Rhee TS, Jin YK, Han S. Mass Budget of Methylmercury in the East Siberian Sea: The Importance of Sediment Sources. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:9949-9957. [PMID: 32660243 DOI: 10.1021/acs.est.0c00154] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Biological concentrations of methylmercury (MeHg) are elevated throughout the Arctic Ocean; however, to date, the major sources and the spatial variability of MeHg are not well quantified. To identify the major inputs and outputs of MeHg to the Arctic shelf water column, we measured MeHg concentrations in the seawater and sediment samples from the East Siberian Sea collected from August to September 2018. We found that the MeHg concentrations in seawater and pore water were higher on the slope than on the shelf, while the MeHg concentrations in the sediment were higher on the shelf than on the slope. We created a mass budget for MeHg and found that the benthic diffusion and resuspension largely exceed other sources, such as atmospheric deposition and river water input. The major sinks of MeHg in the water column were dark demethylation and evasion. When we extrapolated our findings on benthic diffusion to the entire Arctic shelf system, the annual MeHg diffusion from the shelf sediments was estimated to be 23,065 ± 939 mol yr-1, about 2 times higher than previously proposed river discharges. Our study suggests that the MeHg input from shelf sediments in the Arctic Ocean is significant and has been previously underestimated.
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Affiliation(s)
- Jihee Kim
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea
| | - Anne L Soerensen
- Department of Environmental Research and Monitoring, Swedish Museum of Natural History, SE-10405, Stockholm 114 18, Sweden
| | - Mi Seon Kim
- Department of Ocean Environmental Sciences, Chungnam National University, Daejeon 34134, Republic of Korea
- Division of Polar Ocean Sciences, Korea Polar Research Institute, Incheon 21990, Republic of Korea
| | - Sangwoo Eom
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea
| | - Tae Siek Rhee
- Division of Polar Ocean Sciences, Korea Polar Research Institute, Incheon 21990, Republic of Korea
| | - Young Keun Jin
- Division of Polar Earth System Sciences, Korea Polar Research Institute, Incheon 21990, Republic of Korea
| | - Seunghee Han
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea
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5
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Zolkos S, Krabbenhoft DP, Suslova A, Tank SE, McClelland JW, Spencer RGM, Shiklomanov A, Zhulidov AV, Gurtovaya T, Zimov N, Zimov S, Mutter EA, Kutny L, Amos E, Holmes RM. Mercury Export from Arctic Great Rivers. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:4140-4148. [PMID: 32122125 DOI: 10.1021/acs.est.9b07145] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Land-ocean linkages are strong across the circumpolar north, where the Arctic Ocean accounts for 1% of the global ocean volume and receives more than 10% of the global river discharge. Yet estimates of Arctic riverine mercury (Hg) export constrained from direct Hg measurements remain sparse. Here, we report results from a coordinated, year-round sampling program that focused on the six major Arctic rivers to establish a contemporary (2012-2017) benchmark of riverine Hg export. We determine that the six major Arctic rivers exported an average of 20 000 kg y-1 of total Hg (THg, all forms of Hg). Upscaled to the pan-Arctic, we estimate THg flux of 37 000 kg y-1. More than 90% of THg flux occurred during peak river discharge in spring and summer. Normalizing fluxes to watershed area (yield) reveals higher THg yields in regions where greater denudation likely enhances Hg mobilization. River discharge, suspended sediment, and dissolved organic carbon predicted THg concentration with moderate fidelity, while suspended sediment and water yields predicted THg yield with high fidelity. These findings establish a benchmark in the face of rapid Arctic warming and an intensifying hydrologic cycle, which will likely accelerate Hg cycling in tandem with changing inputs from thawing permafrost and industrial activity.
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Affiliation(s)
- Scott Zolkos
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - David P Krabbenhoft
- Upper Midwest Water Science Center, Mercury Research Laboratory, United States Geological Survey, Middleton, Wisconsin 53562, United States
| | - Anya Suslova
- Woods Hole Research Center, Woods Hole, Massachusetts 02540, United States
| | - Suzanne E Tank
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - James W McClelland
- Marine Science Institute, University of Texas at Austin, Port Aransas, Texas 78373, United States
| | - Robert G M Spencer
- Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, Florida 32306, United States
| | - Alexander Shiklomanov
- Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, New Hampshire 03824, United States
| | - Alexander V Zhulidov
- South Russia Centre for Preparation and Implementation of International Projects, Rostov-on-Don 344090, Russia
| | - Tatiana Gurtovaya
- South Russia Centre for Preparation and Implementation of International Projects, Rostov-on-Don 344090, Russia
| | - Nikita Zimov
- Northeast Science Station, Far Eastern Branch of Russian Academy of Science, Chersky 690041, Russia
| | - Sergey Zimov
- Northeast Science Station, Far Eastern Branch of Russian Academy of Science, Chersky 690041, Russia
| | - Edda A Mutter
- Yukon River Inter-Tribal Watershed Council, Anchorage, Alaska 99501, United States
| | - Les Kutny
- Les Kutny Consultant, Inuvik, Northwest Territories X0E 0T0, Canada
| | - Edwin Amos
- Western Arctic Research Centre, Inuvik, Northwest Territories X0E 0T0, Canada
| | - Robert M Holmes
- Woods Hole Research Center, Woods Hole, Massachusetts 02540, United States
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6
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Emmerton CA, Cooke CA, Wentworth GR, Graydon JA, Ryjkov A, Dastoor A. Total Mercury and Methylmercury in Lake Water of Canada's Oil Sands Region. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:10946-10955. [PMID: 30229653 DOI: 10.1021/acs.est.8b01680] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Increased delivery of mercury to ecosystems is a common consequence of industrialization, including in the Athabasca Oil Sands Region (AOSR) of Canada. Atmospheric mercury deposition has been studied previously in the AOSR; however, less is known about the impact of regional industry on toxic methylmercury (MeHg) concentrations in lake ecosystems. We measured total mercury (THg) and MeHg concentrations for five years from 50 lakes throughout the AOSR. Mean lake water concentrations of THg (0.4-5.3 ng L-1) and MeHg (0.01-0.34 ng L-1) were similar to those of other boreal lakes and <5% of all samples exceeded Provincial water quality guidelines. Lakes with the highest THg concentrations were found >100 km northwest of oil sands mines and received runoff from geological formations high in metals concentrations. MeHg concentrations were highest in those lakes, and in smaller productive lakes closer to oil sands mines. Simulated annual average direct deposition of THg to sampled lakes using an atmospheric chemical transport model showed <2% of all mercury deposited to sampled lakes was emitted from oil sands activities. Consequently, spatial patterns of mercury in AOSR lakes were likely most influenced by watershed and lake conditions, though mercury concentrations in these lakes may be perturbed with future development and climatic change.
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Affiliation(s)
- Craig A Emmerton
- Environmental Monitoring and Science Division , Alberta Environment and Parks , Edmonton , Alberta T5J 5C6, Canada
| | - Colin A Cooke
- Environmental Monitoring and Science Division , Alberta Environment and Parks , Edmonton , Alberta T5J 5C6, Canada
| | - Gregory R Wentworth
- Environmental Monitoring and Science Division , Alberta Environment and Parks , Edmonton , Alberta T5J 5C6, Canada
| | | | - Andrei Ryjkov
- Air Quality Research Division , Environment and Climate Change Canada , Dorval , Quebec H9P 1J3, Canada
| | - Ashu Dastoor
- Air Quality Research Division , Environment and Climate Change Canada , Dorval , Quebec H9P 1J3, Canada
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7
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Wang K, Munson KM, Beaupré-Laperrière A, Mucci A, Macdonald RW, Wang F. Subsurface seawater methylmercury maximum explains biotic mercury concentrations in the Canadian Arctic. Sci Rep 2018; 8:14465. [PMID: 30262886 PMCID: PMC6160454 DOI: 10.1038/s41598-018-32760-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 09/12/2018] [Indexed: 01/04/2023] Open
Abstract
Mercury (Hg) is a contaminant of major concern in Arctic marine ecosystems. Decades of Hg observations in marine biota from across the Canadian Arctic show generally higher concentrations in the west than in the east. Various hypotheses have attributed this longitudinal biotic Hg gradient to regional differences in atmospheric or terrestrial inputs of inorganic Hg, but it is methylmercury (MeHg) that accumulates and biomagnifies in marine biota. Here, we present high-resolution vertical profiles of total Hg and MeHg in seawater along a transect from the Canada Basin, across the Canadian Arctic Archipelago (CAA) and Baffin Bay, and into the Labrador Sea. Total Hg concentrations are lower in the western Arctic, opposing the biotic Hg distributions. In contrast, MeHg exhibits a distinctive subsurface maximum at shallow depths of 100–300 m, with its peak concentration decreasing eastwards. As this subsurface MeHg maximum lies within the habitat of zooplankton and other lower trophic-level biota, biological uptake of subsurface MeHg and subsequent biomagnification readily explains the biotic Hg concentration gradient. Understanding the risk of MeHg to the Arctic marine ecosystem and Indigenous Peoples will thus require an elucidation of the processes that generate and maintain this subsurface MeHg maximum.
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Affiliation(s)
- Kang Wang
- Centre for Earth Observation Science, and Department of Environment and Geography, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada
| | - Kathleen M Munson
- Centre for Earth Observation Science, and Department of Environment and Geography, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada
| | - Alexis Beaupré-Laperrière
- GEOTOP, and Department of Earth and Planetary Sciences, McGill University, Montreal, Quebec, H3A 0E8, Canada
| | - Alfonso Mucci
- GEOTOP, and Department of Earth and Planetary Sciences, McGill University, Montreal, Quebec, H3A 0E8, Canada
| | - Robie W Macdonald
- Centre for Earth Observation Science, and Department of Environment and Geography, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada.,Institute of Ocean Sciences, Department of Fisheries and Oceans, Sidney, British Columbia, V8L 4B2, Canada
| | - Feiyue Wang
- Centre for Earth Observation Science, and Department of Environment and Geography, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada.
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Wang J, Liu Q, Chen J, Chen H, Lin H, Sun X. Total mercury flux and offshore transport via submarine groundwater discharge and coal-fired power plant in the Jiulong River estuary, China. MARINE POLLUTION BULLETIN 2018; 127:794-803. [PMID: 29042105 DOI: 10.1016/j.marpolbul.2017.09.064] [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: 07/27/2017] [Revised: 09/23/2017] [Accepted: 09/26/2017] [Indexed: 06/07/2023]
Abstract
A mass balance of total mercury (HgT, dissolved+particulate) is constructed for China's Jiulong River estuary based on measured HgT concentrations in the surface water, sediment, porewater, and groundwater for May, August, and November 2009, combined with data from the literature. The HgT mass budget results show that the dominant source (39-55%) is desulfurized seawater discharged from the Songyu coal-fired power plant. Submarine groundwater discharge (SGD)-derived HgT flux into the estuary is equivalent to 8-58% of the HgT input from the Jiulong River, which is remarkable when compared with SGD-derived HgT fluxes reported in coastal systems worldwide. Hence, SGD is a significant pathway for the transport of HgT into the Jiulong River estuary. The primary HgT sinks is export to the Taiwan Strait (53-88%), which has important environmental implications on the Hg cycling and marine ecosystems in marginal seas.
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Affiliation(s)
- Jigang Wang
- College of Ocean and Earth Sciences, Xiamen University, Xiamen, Fujian 361102, China; Third Institute of Oceanography, State Oceanic Administration, Xiamen, Fujian 361005, China
| | - Qian Liu
- State Key Lab of Marine Environmental Science, Xiamen University, Xiamen, Fujian 361102, China.
| | - Jinmin Chen
- Third Institute of Oceanography, State Oceanic Administration, Xiamen, Fujian 361005, China
| | - Hongzhe Chen
- Third Institute of Oceanography, State Oceanic Administration, Xiamen, Fujian 361005, China
| | - Hui Lin
- Third Institute of Oceanography, State Oceanic Administration, Xiamen, Fujian 361005, China
| | - Xiuwu Sun
- Third Institute of Oceanography, State Oceanic Administration, Xiamen, Fujian 361005, China
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9
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Climate change impacts on environmental and human exposure to mercury in the arctic. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2015; 12:3579-99. [PMID: 25837201 PMCID: PMC4410204 DOI: 10.3390/ijerph120403579] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 03/04/2015] [Accepted: 03/13/2015] [Indexed: 12/03/2022]
Abstract
This paper reviews information from the literature and the EU ArcRisk project to assess whether climate change results in an increase or decrease in exposure to mercury (Hg) in the Arctic, and if this in turn will impact the risks related to its harmful effects. It presents the state-of-the art of knowledge on atmospheric mercury emissions from anthropogenic sources worldwide, the long-range transport to the Arctic, and it discusses the likely environmental fate and exposure effects on population groups in the Arctic under climate change conditions. The paper also includes information about the likely synergy effects (co-benefits) current and new climate change polices and mitigation options might have on mercury emissions reductions in the future. The review concludes that reductions of mercury emission from anthropogenic sources worldwide would need to be introduced as soon as possible in order to assure lowering the adverse impact of climate change on human health. Scientific information currently available, however, is not in the position to clearly answer whether climate change will increase or decrease the risk of exposure to mercury in the Arctic. New research should therefore be undertaken to model the relationships between climate change and mercury exposure.
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10
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Chételat J, Amyot M, Arp P, Blais JM, Depew D, Emmerton CA, Evans M, Gamberg M, Gantner N, Girard C, Graydon J, Kirk J, Lean D, Lehnherr I, Muir D, Nasr M, Poulain AJ, Power M, Roach P, Stern G, Swanson H, van der Velden S. Mercury in freshwater ecosystems of the Canadian Arctic: recent advances on its cycling and fate. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 509-510:41-66. [PMID: 24993511 DOI: 10.1016/j.scitotenv.2014.05.151] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 05/01/2014] [Accepted: 05/27/2014] [Indexed: 06/03/2023]
Abstract
The Canadian Arctic has vast freshwater resources, and fish are important in the diet of many Northerners. Mercury is a contaminant of concern because of its potential toxicity and elevated bioaccumulation in some fish populations. Over the last decade, significant advances have been made in characterizing the cycling and fate of mercury in these freshwater environments. Large amounts of new data on concentrations, speciation and fluxes of Hg are provided and summarized for water and sediment, which were virtually absent for the Canadian Arctic a decade ago. The biogeochemical processes that control the speciation of mercury remain poorly resolved, including the sites and controls of methylmercury production. Food web studies have examined the roles of Hg uptake, trophic transfer, and diet for Hg bioaccumulation in fish, and, in particular, advances have been made in identifying determinants of mercury levels in lake-dwelling and sea-run forms of Arctic char. In a comparison of common freshwater fish species that were sampled across the Canadian Arctic between 2002 and 2009, no geographic patterns or regional hotspots were evident. Over the last two to four decades, Hg concentrations have increased in some monitored populations of fish in the Mackenzie River Basin while other populations from the Yukon and Nunavut showed no change or a slight decline. The different Hg trends indicate that the drivers of temporal change may be regional or habitat-specific. The Canadian Arctic is undergoing profound environmental change, and preliminary evidence suggests that it may be impacting the cycling and bioaccumulation of mercury. Further research is needed to investigate climate change impacts on the Hg cycle as well as biogeochemical controls of methylmercury production and the processes leading to increasing Hg levels in some fish populations in the Canadian Arctic.
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Affiliation(s)
- John Chételat
- Environment Canada, National Wildlife Research Centre, Ottawa, Ontario K1A 0H3, Canada.
| | - Marc Amyot
- Centre d'études nordiques, Département de sciences biologiques, Université de Montréal, Montreal, Quebec H3C 3J7, Canada
| | - Paul Arp
- Faculty of Forestry and Environmental Management, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada
| | - Jules M Blais
- Department of Biology, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - David Depew
- Environment Canada, Canada Centre for Inland Waters, Burlington, Ontario L7R 4A6, Canada
| | - Craig A Emmerton
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Marlene Evans
- Environment Canada, Aquatic Contaminants Research Division, Saskatoon, Saskatchewan S7N 3H5, Canada
| | - Mary Gamberg
- Gamberg Consulting, Whitehorse, Yukon Y1A 5M2, Canada
| | - Nikolaus Gantner
- Department of Geography, University of Victoria, Victoria, BC V8W 3R4, Canada
| | - Catherine Girard
- Centre d'études nordiques, Département de sciences biologiques, Université de Montréal, Montreal, Quebec H3C 3J7, Canada
| | - Jennifer Graydon
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Jane Kirk
- Environment Canada, Canada Centre for Inland Waters, Burlington, Ontario L7R 4A6, Canada
| | - David Lean
- Lean Environmental, Apsley, Ontario K0L 1A0, Canada
| | - Igor Lehnherr
- Earth and Environmental Sciences, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Derek Muir
- Environment Canada, Canada Centre for Inland Waters, Burlington, Ontario L7R 4A6, Canada
| | - Mina Nasr
- Faculty of Forestry and Environmental Management, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada
| | - Alexandre J Poulain
- Department of Biology, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Michael Power
- Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Pat Roach
- Aboriginal Affairs and Northern Development Canada, Whitehorse, Yukon Y1A 2B5, Canada
| | - Gary Stern
- Centre for Earth Observation Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Heidi Swanson
- Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
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11
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Dastoor AP, Durnford DA. Arctic Ocean: is it a sink or a source of atmospheric mercury? ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:1707-1717. [PMID: 24328426 DOI: 10.1021/es404473e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
High levels of mercury in marine mammals threaten the health of Arctic inhabitants. Whether the Arctic Ocean (AO) is a sink or a source of atmospheric mercury is unknown. Given the paucity of observations in the Arctic, models are useful in addressing this question. GEOS-Chem and GRAHM, two complex numerical mercury models, present contrasting pictures of atmospheric mercury input to AO at 45 and 108 Mg yr(-1), respectively, and ocean evasion at 90 and 33 Mg yr(-1), respectively. We provide a comprehensive evaluation of GRAHM simulated atmospheric mercury input to AO using mercury observations in air, precipitation and snowpacks, and an analysis of the discrepancy between the two modeling estimates using observations. We discover two peaks in high-latitude summertime concentrations of atmospheric mercury. We show that the first is caused mainly by snowmelt revolatilization and the second by AO evasion of mercury. Riverine mercury export to AO is estimated at 50 Mg yr(-1) based on measured DOC export and at 15.5-31 Mg yr(-1) based on simulated mercury in meltwater. The range of simulated mercury fluxes to and from AO reflects uncertainties in modeling mercury in the Arctic; comprehensive observations in all compartments of the Arctic ecosystem are needed to close the gap.
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Affiliation(s)
- Ashu P Dastoor
- Air Quality Research Division, Environment Canada , 2121 TransCanada Highway, Dorval, Quebec H9P 1J3, Canada
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12
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Evans M, Muir D, Brua RB, Keating J, Wang X. Mercury trends in predatory fish in Great Slave Lake: the influence of temperature and other climate drivers. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:12793-12801. [PMID: 24111928 DOI: 10.1021/es402645x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Here we report on trends in mercury (Hg) concentrations in lake trout (Salvelinus namaycush), burbot (Lota lota), and northern pike (Esox lucius) from Great Slave Lake, located in the Mackenzie River Basin (MRB) and investigate how climate factors may be influencing these trends. Hg concentrations in lake trout and burbot increased significantly over the early 1990s to 2012 in the two major regions of the lake; no trend was evident for northern pike over 1999-2012. Temporal variations in Hg concentrations in lake trout and burbot were similar with respect to timing of peaks and troughs. Inclusion of climate variables based on annual means, particularly temperature, improved explanatory power for variations in Hg over analyses based only on year and fish length; unexpectedly, the temperature coefficient was negative. Climate analyses based on growing season means (defined as May-September) had less explanatory power suggesting that trends were more strongly associated with colder months within the year. Inclusion of the Pacific/North American index improved explanatory power for the lake trout model suggesting that trends may have been affected by air circulation patterns. Overall, while our study confirmed previously reported trends of Hg increase in burbot in the MRB, we found no evidence that these trends were directly driven by increasing temperatures and productivity.
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Affiliation(s)
- Marlene Evans
- Aquatic Contaminants Research Division, Environment Canada , Saskatoon, Saskatchewan, Canada S7N 3H5
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13
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Emmerton CA, Graydon JA, Gareis JAL, St Louis VL, Lesack LFW, Banack JKA, Hicks F, Nafziger J. Mercury export to the Arctic Ocean from the Mackenzie River, Canada. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:7644-7654. [PMID: 23800098 DOI: 10.1021/es400715r] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Circumpolar rivers, including the Mackenzie River in Canada, are sources of the contaminant mercury (Hg) to the Arctic Ocean, but few Hg export studies exist for these rivers. During the 2007-2010 freshet and open water seasons, we collected river water upstream and downstream of the Mackenzie River delta to quantify total mercury (THg) and methylmercury (MeHg) concentrations and export. Upstream of the delta, flow-weighted mean concentrations of bulk THg and MeHg were 14.6 ± 6.2 ng L(-1) and 0.081 ± 0.045 ng L(-1), respectively. Only 11-13% and 44-51% of bulk THg and MeHg export was in the dissolved form. Using concentration-discharge relationships, we calculated bulk THg and MeHg export into the delta of 2300-4200 kg yr(-1) and 15-23 kg yr(-1) over the course of the study. Discharge is not presently known in channels exiting the delta, so we assessed differences in river Hg concentrations upstream and downstream of the delta to estimate its influence on Hg export to the ocean. Bulk THg and MeHg concentrations decreased 19% and 11% through the delta, likely because of particle settling and other processes in the floodplain. These results suggest that northern deltas may be important accumulators of river Hg in their floodplains before export to the Arctic Ocean.
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Affiliation(s)
- Craig A Emmerton
- Department of Biological Sciences, University of Alberta , Edmonton, Alberta T6G 2E9, Canada.
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14
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Wang F, Macdonald RW, Armstrong DA, Stern GA. Total and methylated mercury in the Beaufort Sea: the role of local and recent organic remineralization. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:11821-8. [PMID: 23025753 DOI: 10.1021/es302882d] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Mercury is a major contaminant in the Arctic marine ecosystem. While extensive studies have been conducted on mercury in the Arctic's atmosphere and biota, far less is known about the distribution and dynamics of mercury species in the Arctic Ocean. Here, we present vertical profiles for total mercury (Hg(T)) and total methylated mercury (MeHg(T), sum of monomethylmercury and dimethylmercury) from the Beaufort Sea of the Arctic Ocean at locations with differing sea ice conditions. The concentration of Hg(T) ranged from 0.40 to 2.9 pM, with a surface enrichment that can be attributed to a combination of sea ice-modified atmospheric deposition and riverine input. The concentration of MeHg(T) ranged from <0.04 to 0.59 pM, with a subsurface peak occurring at the same depth as a nutrient maximum with lower dissolved oxygen, which is consistent with the recent findings in the Pacific Ocean, Southern Ocean, and Mediterranean Sea. However, unlike the interior ocean regions, the nutrient maximum in the Beaufort Sea is predominantly an advective feature produced over the Chukchi Shelf. On the basis of the short lifetime of monomethylmercury in seawater, we propose that the MeHg(T) profile in the Beaufort Sea reflects the local, short-term remineralization of labile organic matter, and not the larger signal of organic remineralization advected from the Chukchi Sea in the halocline. The finding that MeHg(T) is produced locally, reflecting recent strength of organic matter cycling, not only explains wide variance in MeHg(T) in seawater and biota over time and space, but also implies that MeHg(T) could be used as an indicator of the recent export flux of labile organic matter.
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Affiliation(s)
- Feiyue Wang
- Center for Earth Observation Science, Department of Environment and Geography, University of Manitoba, Winnipeg, MB, Canada R3T 2N2.
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15
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Kirk JL, Lehnherr I, Andersson M, Braune BM, Chan L, Dastoor AP, Durnford D, Gleason AL, Loseto LL, Steffen A, St Louis VL. Mercury in Arctic marine ecosystems: sources, pathways and exposure. ENVIRONMENTAL RESEARCH 2012; 119:64-87. [PMID: 23102902 PMCID: PMC4142812 DOI: 10.1016/j.envres.2012.08.012] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Revised: 08/02/2012] [Accepted: 08/13/2012] [Indexed: 05/20/2023]
Abstract
Mercury in the Arctic is an important environmental and human health issue. The reliance of Northern Peoples on traditional foods, such as marine mammals, for subsistence means that they are particularly at risk from mercury exposure. The cycling of mercury in Arctic marine systems is reviewed here, with emphasis placed on the key sources, pathways and processes which regulate mercury levels in marine food webs and ultimately the exposure of human populations to this contaminant. While many knowledge gaps exist limiting our ability to make strong conclusions, it appears that the long-range transport of mercury from Asian emissions is an important source of atmospheric Hg to the Arctic and that mercury methylation resulting in monomethylmercury production (an organic form of mercury which is both toxic and bioaccumulated) in Arctic marine waters is the principal source of mercury incorporated into food webs. Mercury concentrations in biological organisms have increased since the onset of the industrial age and are controlled by a combination of abiotic factors (e.g., monomethylmercury supply), food web dynamics and structure, and animal behavior (e.g., habitat selection and feeding behavior). Finally, although some Northern Peoples have high mercury concentrations of mercury in their blood and hair, harvesting and consuming traditional foods have many nutritional, social, cultural and physical health benefits which must be considered in risk management and communication.
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Affiliation(s)
- Jane L Kirk
- Environment Canada, Aquatic Contaminants Research Division, 867 Lakeshore Dr, Burlington, ON L7R 4A6, Canada.
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16
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Navarro P, Amouroux D, Thanh ND, Rochelle-Newall E, Ouillon S, Arfi R, Van TC, Mari X, Torréton JP. Fate and tidal transport of butyltin and mercury compounds in the waters of the tropical Bach Dang Estuary (Haiphong, Vietnam). MARINE POLLUTION BULLETIN 2012; 64:1789-1798. [PMID: 22717320 DOI: 10.1016/j.marpolbul.2012.05.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 05/15/2012] [Accepted: 05/23/2012] [Indexed: 06/01/2023]
Abstract
In this work, two field campaigns were performed in July 2008 (wet season) and March 2009 (dry season) to produce original data on the concentration, partition and distribution of mercury and butyltin compounds along the tropical Bach Dang Estuary located in North Vietnam (Haiphong, Red River Delta). The results demonstrate that mercury and butyltin speciation in the surface waters of this type of tropical estuary is greatly affected by the drastic changes in the seasonal conditions. During high river discharge in the wet season, there was a large estuarine input of total Hg and tributyltin, while the longer residence time of the waters during the dry season promotes increasing MMHg formation and TBT degradation. Although most of the Hg and TBT is transported into the estuary from upstream sources, tidal cycle measurements demonstrate that this estuary is a significant source of TBT and MMHg during the wet (~3 kg TBT/day) and dry (~3 g MMHg/day) seasons.
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Affiliation(s)
- Patricia Navarro
- Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, UMR 5254 IPREM, CNRS, Université de Pau et des Pays de l'Adour, 2 Avenue Président Pierre Angot, 64053 Pau, France
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17
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Lee YG, Rahman MM, Kim G, Han S. Mass balance of total mercury and monomethylmercury in coastal embayments of a volcanic island: significance of submarine groundwater discharge. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:9891-9900. [PMID: 21973173 DOI: 10.1021/es202093z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
To understand the contribution of submarine groundwater discharge (SGD) to the coastal mass budgets of Hg and monomethylmercury (MMHg), preliminary mass balance estimates were made for Hwasun and Bangdu Bays on Jeju Island, known to have large SGD due to the high permeability of the volcanic rocks. The mass balance results indicate that SGD is a main source of Hg in Hwasun Bay (23 ± 14 × 10(-2) mol yr(-1), 34%) and Bangdu Bay (23 ± 20 × 10(-2) mol yr(-1), 67%), although the contribution from atmospheric deposition was considerable (25% for Hwasun and 23% for Bangdu). MMHg was also discharged primarily from submarine groundwater at Hwasun (0.30 ± 0.17 × 10(-2) mol yr(-1), 55%) and Bangdu (0.65 ± 0.49 × 10(-2) mol yr(-1), 64%), which was higher than atmospheric deposition (6% for Hwasun and 2% for Bangdu) and sediment diffusion flux (5% for Hwasun and 3% for Bangdu). The overall mass balance results suggest that, although there are large spatial variations in SGD rates throughout the region, the coastal mass budgets of Hg and MMHg need to include SGD as well as atmospheric deposition and sediment diffusion as primary sources of Hg and MMHg.
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Affiliation(s)
- Yong-gu Lee
- School of Environment Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712, Korea
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18
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St Louis VL, Derocher AE, Stirling I, Graydon JA, Lee C, Jocksch E, Richardson E, Ghorpade S, Kwan AK, Kirk JL, Lehnherr I, Swanson HK. Differences in mercury bioaccumulation between polar bears (Ursus maritimus) from the Canadian high- and sub-Arctic. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:5922-5928. [PMID: 21678897 DOI: 10.1021/es2000672] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Polar bears (Ursus maritimus) are being impacted by climate change and increased exposure to pollutants throughout their northern circumpolar range. In this study, we quantified concentrations of total mercury (THg) in the hair of polar bears from Canadian high- (southern Beaufort Sea, SBS) and sub- (western Hudson Bay, WHB) Arctic populations. Concentrations of THg in polar bears from the SBS population (14.8 ± 6.6 μg g(-1)) were significantly higher than in polar bears from WHB (4.1 ± 1.0 μg g(-1)). On the basis of δ(15)N signatures in hair, in conjunction with published δ(15)N signatures in particulate organic matter and sediments, we estimated that the pelagic and benthic food webs in the SBS are ∼ 4.7 and ∼ 4.0 trophic levels long, whereas in WHB they are only ∼ 3.6 and ∼ 3.3 trophic levels long. Furthermore, the more depleted δ(13)C ratios in hair from SBS polar bears relative to those from WHB suggests that SBS polar bears feed on food webs that are relatively more pelagic (and longer), whereas polar bears from WHB feed on those that are relatively more benthic (and shorter). Food web length and structure accounted for ∼ 67% of the variation we found in THg concentrations among all polar bears across both populations. The regional difference in polar bear hair THg concentrations was also likely due to regional differences in water-column concentrations of methyl Hg (the toxic form of Hg that biomagnifies through food webs) available for bioaccumulation at the base of the food webs. For example, concentrations of methylated Hg at mid-depths in the marine water column of the northern Canadian Arctic Archipelago were 79.8 ± 37.3 pg L(-1), whereas, in HB, they averaged only 38.3 ± 16.6 pg L(-1). We conclude that a longer food web and higher pelagic concentrations of methylated Hg available to initiate bioaccumulation in the BS resulted in higher concentrations of THg in polar bears from the SBS region compared to those inhabiting the western coast of HB.
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Affiliation(s)
- Vincent L St Louis
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
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19
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Carrie J, Wang F, Sanei H, Macdonald RW, Outridge PM, Stern GA. Increasing contaminant burdens in an arctic fish, Burbot ( Lota lota ), in a warming climate. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:316-22. [PMID: 19957995 DOI: 10.1021/es902582y] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The temporal patterns of mercury (Hg), polychlorinated biphenyls (PCBs), and other contaminants in Arctic aquatic biota are usually attributed to changing atmospheric sources. However, climate variability and change is another means of altering contaminant fate and bioavailability. We show here that the concentrations of Hg and PCBs in Mackenzie River burbot ( Lota lota ), a top predator fish and important staple food for northern Canadian communities, have increased significantly over the last 25 years despite falling or stable atmospheric concentrations, suggesting that environmental processes subsequent to atmospheric transport are responsible. Using a dated sediment core from a tributary lake near the Mackenzie River sampling site, we show that variations in Hg concentrations downcore are strongly associated with labile, algal-derived organic matter (OM). Strong temporal correlations between increasing primary productivity and biotic Hg and PCBs as reflected by burbot suggest that warming temperatures and reduced ice cover may lead to increased exposure to these contaminants in high trophic level Arctic freshwater biota.
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Affiliation(s)
- J Carrie
- Centre for Earth Observation Science, Department of Environment & Geography, University of Manitoba, 125 Dysart Road, Winnipeg, Manitoba R3T 2N2, Canada
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