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Zhang Z, Zhang Z, Zhang C, Chang Q, Fang Q, Liao C, Chen J, Alvarez PJJ, Chen W, Zhang T. Simultaneous Reduction and Methylation of Nanoparticulate Mercury: The Critical Role of Extracellular Electron Transfer. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:18368-18378. [PMID: 39370945 DOI: 10.1021/acs.est.4c07573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/08/2024]
Abstract
Mercury nanoparticles are abundant in natural environments. Yet, understanding their contribution to global biogeochemical cycling of mercury remains elusive. Here, we show that microbial transformation of nanoparticulate divalent mercury can be an important source of elemental and methylmercury.Geobacter sulfurreducensPCA, a model bacterium predominant in anoxic environments (e.g., paddy soils), simultaneously reduces and methylates nanoparticulate Hg(II). Moreover, the relative prevalence of these two competing processes and the dominant transformation pathways differ markedly between nanoparticulate Hg(II) and its dissolved and bulk-sized counterparts. Notably, even when intracellular reduction of Hg(II) nanoparticles is constrained by cross-membrane transport (a rate-limiting step that also regulates methylation), the overall Hg(0) formation remains substantial due to extracellular electron transfer. With multiple lines of evidence based on microscopic and electrochemical analyses, gene knockout experiments, and theoretical calculations, we show that nanoparticulate Hg(II) is preferentially associated with c-type cytochromes on cell membranes and has a higher propensity for accepting electrons from the heme groups than adsorbed ionic Hg(II), which explains the surprisingly larger extent of reduction of nanoparticles than dissolved Hg(II) at relatively high mercury loadings. These findings have important implications for the assessment of global mercury budgets as well as the bioavailability of nanominerals and mineral nanoparticles.
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Affiliation(s)
- Zhiying 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, 38 Tongyan Road, Tianjin 300350, China
| | - Zhanhua 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, 38 Tongyan Road, Tianjin 300350, China
| | - Chenyang 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, 38 Tongyan Road, Tianjin 300350, China
| | - Qing Chang
- 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, 38 Tongyan Road, Tianjin 300350, China
| | - Qingxuan Fang
- 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, 38 Tongyan Road, Tianjin 300350, China
| | - Chengmei Liao
- 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, 38 Tongyan Road, Tianjin 300350, China
- School of Ecology and Environment, Inner Mongolia University, 235 West College Road, Hohhot 010021, China
| | - Jiubin Chen
- School of Earth System Science, Tianjin University, 92 Weijin Road, Tianjin 300072, China
| | - Pedro J J Alvarez
- Department of Civil and Environmental Engineering, Rice University, 6100 Main Street, Houston, Texas 77005, United States
| | - Wei Chen
- 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, 38 Tongyan Road, Tianjin 300350, 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, 38 Tongyan Road, Tianjin 300350, China
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2
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Feinberg A, Selin NE, Braban CF, Chang KL, Custódio D, Jaffe DA, Kyllönen K, Landis MS, Leeson SR, Luke W, Molepo KM, Murovec M, Nerentorp Mastromonaco MG, Aspmo Pfaffhuber K, Rüdiger J, Sheu GR, St Louis VL. Unexpected anthropogenic emission decreases explain recent atmospheric mercury concentration declines. Proc Natl Acad Sci U S A 2024; 121:e2401950121. [PMID: 39378086 DOI: 10.1073/pnas.2401950121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 09/05/2024] [Indexed: 10/10/2024] Open
Abstract
Anthropogenic activities emit ~2,000 Mg y-1 of the toxic pollutant mercury (Hg) into the atmosphere, leading to long-range transport and deposition to remote ecosystems. Global anthropogenic emission inventories report increases in Northern Hemispheric (NH) Hg emissions during the last three decades, in contradiction with the observed decline in atmospheric Hg concentrations at NH measurement stations. Many factors can obscure the link between anthropogenic emissions and atmospheric Hg concentrations, including trends in the reemissions of previously released anthropogenic ("legacy") Hg, atmospheric sink variability, and spatial heterogeneity of monitoring data. Here, we assess the observed trends in gaseous elemental mercury (Hg0) in the NH and apply biogeochemical box modeling and chemical transport modeling to understand the trend drivers. Using linear mixed effects modeling of observational data from 51 stations, we find negative Hg0 trends in most NH regions, with an overall trend for 2005 to 2020 of -0.011 ± 0.006 ng m-3 y-1 (±2 SD). In contrast to existing emission inventories, our modeling analysis suggests that annual NH anthropogenic emissions must have declined by at least 140 Mg between the years 2005 and 2020 to be consistent with observed trends. Faster declines in 95th percentile Hg0 values than median values in Europe, North America, and East Asian measurement stations corroborate that the likely cause is a decline in nearby anthropogenic emissions rather than background legacy reemissions. Our results are relevant for evaluating the effectiveness of the Minamata Convention on Mercury, demonstrating that existing emission inventories are incompatible with the observed Hg0 declines.
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Affiliation(s)
- Aryeh Feinberg
- Institute for Data, Systems, and Society, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Noelle E Selin
- Institute for Data, Systems, and Society, Massachusetts Institute of Technology, Cambridge, MA 02139
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Christine F Braban
- United Kingdom Centre for Ecology and Hydrology, Penicuik, Midlothian EH26 0QB, United Kingdom
| | - Kai-Lan Chang
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309
- National Oceanic and Atmospheric Administration Chemical Sciences Laboratory, Boulder, CO 80305
| | | | - Daniel A Jaffe
- School of Science, Technology, Engineering & Mathematics, Physical Sciences Division, University of Washington Bothell, Bothell, WA 98011
- Department of Atmospheric Sciences, University of Washington Seattle, Seattle, WA 98195
| | - Katriina Kyllönen
- Atmospheric Composition Research, Finnish Meteorological Institute, Helsinki 00560, Finland
| | - Matthew S Landis
- United States Environmental Protection Agency, Office of Research and Development, Research Triangle Park, NC 27711
| | - Sarah R Leeson
- United Kingdom Centre for Ecology and Hydrology, Penicuik, Midlothian EH26 0QB, United Kingdom
| | - Winston Luke
- National Oceanic and Atmospheric Administration/Air Resources Laboratory, College Park, MD 20740
| | - Koketso M Molepo
- Institute of Coastal Environmental Chemistry, Helmholtz Zentrum Hereon, Geesthacht 21502, Germany
| | - Marijana Murovec
- Slovenian Environment Agency, Environment and Nature protection Office, Air Quality Division, Ljubljana 1000, Slovenia
| | | | | | - Julian Rüdiger
- Air Monitoring Network, German Environment Agency, Langen 63225, Germany
| | - Guey-Rong Sheu
- Department of Atmospheric Sciences, National Central University, Taoyuan 320, Taiwan
| | - Vincent L St Louis
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
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3
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Fabre C, Sonke JE, Tananaev N, Teisserenc R. Organic carbon and mercury exports from pan-Arctic rivers in a thawing permafrost context - A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 954:176713. [PMID: 39389136 DOI: 10.1016/j.scitotenv.2024.176713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2024] [Revised: 09/06/2024] [Accepted: 10/02/2024] [Indexed: 10/12/2024]
Abstract
Climate change affects more than elsewhere the northern circumpolar permafrost region. This zone comprises large rivers flowing mainly to the Arctic Ocean, delivering about 10 % of the global riverine water flux. These pan-Arctic Rivers drive the dynamics of northern organic carbon (OC) and mercury (Hg) cycling. Permafrost degradation may release substantial amounts of OC and Hg, with potential regional and global impacts. In this review, we summarise the main findings in the last three decades about the role of the pan-Arctic Rivers in OC and Hg cycling and the effect of climate change on these dynamics. Total DOC and POC fluxes delivered by the pan-Arctic rivers presently reach 34.4 ± 1.2 TgC·yr-1 and 7.9 ± 0.5 TgC·yr-1, while the export of Hg reaches 38.9 ± 1.7 Mg·yr-1. This review highlights future challenges for the scientific community in evaluating spatial and temporal dynamics of the processes involved in OC and Hg cycling in permafrost-affected areas. Permafrost thawing could lead to greater fluxes of OC and Hg with ill-known resulting risks for food chains. Within this context, efforts should be made to study OC effects on Hg methylation. Moreover, assessing the spatial variability of OC and Hg mobilisation and transport within the pan-Arctic watersheds may help understand the future OC and Hg cycling dynamics in the northern circumpolar permafrost region.
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Affiliation(s)
- Clément Fabre
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland; Laboratoire Ecologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, INPT, UPS, Avenue de l'Agrobiopole, 31326 Auzeville-Tolosane, France.
| | - Jeroen E Sonke
- Geosciences Environnement Toulouse, CNRS/IRD/CNES/Université Toulouse III, 14 avenue Edouard Belin, 31400 Toulouse, France
| | - Nikita Tananaev
- Melnikov Permafrost Institute, SB RAS, Yakutsk 677010, Russia
| | - Roman Teisserenc
- Laboratoire Ecologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, INPT, UPS, Avenue de l'Agrobiopole, 31326 Auzeville-Tolosane, France
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Gong C, Wen L, Lu H, Wang S, Liu J, Xia X, Liao Z, Wangzha D, Zhaxi W, Tudan J, Tan C. Ecological, environmental risks and sources of arsenic and other elements in soils of Tuotuo River region, Qinghai-Tibet Plateau. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2024; 46:460. [PMID: 39352522 PMCID: PMC11457720 DOI: 10.1007/s10653-024-02161-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2024] [Accepted: 08/01/2024] [Indexed: 10/09/2024]
Abstract
Against the backdrop of global warming, the pollutants that were once "temporarily stored" in the permafrost are gradually being released, posing significant impacts on the environment. This has become an internationally focused hot topic. In this study, the contents of 11 elements such as As, Ti, Cd, Cr, Co, Mn, Cu, Pb, Ni, Zn and V in soil samples from 128 sampling points in the freeze-thaw area of the Tuotuo River in the source region of the Yangtze River on the Qinghai-Tibet Plateau were determined to evaluate the possible sources, contamination status and ecological, environmental and health risks of these elements. The mean values of As, Cd, Pb and Zn were higher than the corresponding Tibet soil background values. Among fourteen PTEs, As, Cd and Pb had the highest average values of enrichment factor and pollution index, indicating that freeze-thaw area soils showed moderate enrichment and pollution with As, Cd and Pb. Mean ecological risk factor (ER) of Cd was 109 and other PTEs mean ER values < 40, whereas ecological risk index (RI) values of all PTEs ranged from 59.5 to 880 and mean RI values was 152, indicating moderate ecological risk in study area. Explanatory power q value of total S (TS) content was 0.217 by GeogDetector, indicating TS was the most significant contributing factor to RI. Correlation analysis and PCA analysis showed that Cr, Cu, Ni, Co, Mn, Ti, V were mainly originated from natural sources, Cd, Pb and Zn from traffic activity, As from long-distance migration-freeze-thaw.
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Affiliation(s)
- Cang Gong
- Key Laboratory of Natural Resource Coupling Process and Effects, Beijing, 100055, China
- Research Center of Applied Geology of China Geological Survey, Chengdu, 610039, China
| | - Lang Wen
- Key Laboratory of Natural Resource Coupling Process and Effects, Beijing, 100055, China.
- Research Center of Applied Geology of China Geological Survey, Chengdu, 610039, China.
| | - Haichuan Lu
- Key Laboratory of Natural Resource Coupling Process and Effects, Beijing, 100055, China
- Research Center of Applied Geology of China Geological Survey, Chengdu, 610039, China
| | - Shunxiang Wang
- Key Laboratory of Natural Resource Coupling Process and Effects, Beijing, 100055, China
- Research Center of Applied Geology of China Geological Survey, Chengdu, 610039, China
| | - Jiufen Liu
- Key Laboratory of Natural Resource Coupling Process and Effects, Beijing, 100055, China
- Research Center of Applied Geology of China Geological Survey, Chengdu, 610039, China
- Natural Resources Comprehensive Survey Command Center of China Geological Survey, Beijing, 100055, China
| | - Xiang Xia
- Key Laboratory of Natural Resource Coupling Process and Effects, Beijing, 100055, China
- Research Center of Applied Geology of China Geological Survey, Chengdu, 610039, China
| | - Zihong Liao
- Research Center of Applied Geology of China Geological Survey, Chengdu, 610039, China
| | - Duoji Wangzha
- Research Center of Applied Geology of China Geological Survey, Chengdu, 610039, China
| | - Wangdui Zhaxi
- Research Center of Applied Geology of China Geological Survey, Chengdu, 610039, China
| | - Jiancai Tudan
- Research Center of Applied Geology of China Geological Survey, Chengdu, 610039, China
| | - Changhai Tan
- Key Laboratory of Natural Resource Coupling Process and Effects, Beijing, 100055, China.
- Research Center of Applied Geology of China Geological Survey, Chengdu, 610039, China.
- College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000, China.
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5
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Franzaring J, Haneke J, Sannino A, Radermacher G, Schweiger A. Effects of legacy mining on mercury concentrations in conifer needles and mushrooms in northern Palatinate, Germany. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 357:124406. [PMID: 38925211 DOI: 10.1016/j.envpol.2024.124406] [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: 02/01/2024] [Revised: 05/28/2024] [Accepted: 06/18/2024] [Indexed: 06/28/2024]
Abstract
Due to integrated pollution prevention and control measures and the reduced burning of coal, air concentrations of mercury (Hg0) are currently levelling off. In the future, however, evasion from land surfaces will probably reverse this trend. Reasons are the rising temperatures and the loss of forest cover caused by calamities, droughts, storms and wildfires. Plant leaves constitute an important matrix for the accumulation of gaseous mercury and uptake and re-volatilisation by plants depends on the species, the vitality and the age and morphology of leaf organs. It has been shown that older conifer needles show higher concentrations than young needles and Hg accumulation is increasing throughout the season. In present study, we collected branches from Norway Spruce (Picea abies) in a former cinnabar mining region in Northern Palatinate, where artisanal and small-scale mining left innumerable waste dumps. While mining, smelting and processing of the ores were terminated during WWII, high total mercury concentrations remained in the top soils locally, with presumably only small fractions being plant available. In the lab, up to seven needle age classes were analysed. 1000 needle weights increased with age and as expected, also the Hg concentrations were elevated in the older needles. Needle concentrations were higher than those reported from other national biomonitoring programs confirming the regional imprint from legacy mercury. To complement our biomonitoring study, we collected edible mushrooms in former mining areas. Hg concentrations in most samples exceeded the EU maximum residue levels (MRL), while only a few broke the existing cadmium and lead limits. Tolerable weekly intake (TWI) for inorganic mercury would be surpassed with the consumption of a small portion of mushrooms. Further studies should be performed on the outgassing of Hg from mine wastes and the incorporation of Hg in the local food web, including its methylation and biomagnification.
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Affiliation(s)
- Jürgen Franzaring
- University of Hohenheim, Institute of Landscape and Plant Ecology, Department of Plant Ecology, Stuttgart, Germany.
| | - Jost Haneke
- The Palatinate Mining Museum Imsbach e.V., Imsbach, Germany
| | - Adele Sannino
- Core Facility Hohenheim (CFH), Analytical Chemistry Unit, Stuttgart, Germany
| | - Georg Radermacher
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Schmallenberg, Germany
| | - Andreas Schweiger
- University of Hohenheim, Institute of Landscape and Plant Ecology, Department of Plant Ecology, Stuttgart, Germany
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Guo W, Liu M, Zhang Q, Deng Y, Chu Z, Qin H, Li Y, Liu YR, Zhang H, Zhang W, Tao S, Wang X. Warming-Induced Vegetation Greening May Aggravate Soil Mercury Levels Worldwide. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024. [PMID: 39140482 DOI: 10.1021/acs.est.4c01923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2024]
Abstract
Mercury, a neurotoxic substance, circulates globally, significantly stored in soils through atmospheric deposition and plant decay. Despite being deposited, mercury can be remobilized and released into the atmosphere and water, enhancing its global cycle. Recent research suggests that climate warming may amplify the remobilization of soil mercury, facilitating its incorporation into food webs that humans exploit. However, the potential geospatial feedback of soil mercury levels in response to warming remains unclear. By leveraging up-to-date soil measurements and observation-driven models, we determined the amount of mercury stored in global 0-100 cm soils to be 4.3 Tg (interquartile range: 2.5-6.3 Tg). Furthermore, our analysis indicates that warming likely aggravates global soil mercury levels, particularly in many temperate areas in East Asia, North Europe, and North America (>20 ng g-1 increase by 2100) due to warming-induced vegetation greening. Critically, observation-driven models raise the possibility that implementing ambitious mercury-emission-control schemes alone may be insufficient to counterbalance the positive feedback of soil mercury concentration, while process-based biogeochemical modeling demonstrates consistent patterns that reinforce this concern. These findings hold broad implications; for example, such feedback may catalyze mercury remobilization in land-ocean continuums and exacerbate human risks, stressing the necessity for continued reductions in greenhouse gas and mercury emissions.
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Affiliation(s)
- Wenzhe Guo
- Ministry of Education Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Maodian Liu
- Ministry of Education Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
- School of the Environment, Yale University, New Haven, Connecticut 06511, United States
| | - Qianru Zhang
- Ministry of Education Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
- Nicholas School of the Environment, Duke University, Durham, North Carolina 27708, United States
| | - Yidan Deng
- Ministry of Education Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Zhaohan Chu
- Ministry of Education Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Hehao Qin
- Ministry of Education Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Yangmingkai Li
- Ministry of Education Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Yu-Rong Liu
- College of Resources and Environment and State Environmental Protection Key Laboratory of Soil Health and Green Remediation, Huazhong Agricultural University, Wuhan 430070, China
| | - Haoran Zhang
- The Bartlett School of Sustainable Construction, University College London, London WC1E 7HB, U.K
| | - Wei Zhang
- Ministry of Education Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Shu Tao
- Ministry of Education Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Xuejun Wang
- Ministry of Education Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
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Espinoza JL, Phillips A, Prentice MB, Tan GS, Kamath PL, Lloyd KG, Dupont CL. Unveiling the microbial realm with VEBA 2.0: a modular bioinformatics suite for end-to-end genome-resolved prokaryotic, (micro)eukaryotic and viral multi-omics from either short- or long-read sequencing. Nucleic Acids Res 2024; 52:e63. [PMID: 38909293 DOI: 10.1093/nar/gkae528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 05/21/2024] [Accepted: 06/10/2024] [Indexed: 06/24/2024] Open
Abstract
The microbiome is a complex community of microorganisms, encompassing prokaryotic (bacterial and archaeal), eukaryotic, and viral entities. This microbial ensemble plays a pivotal role in influencing the health and productivity of diverse ecosystems while shaping the web of life. However, many software suites developed to study microbiomes analyze only the prokaryotic community and provide limited to no support for viruses and microeukaryotes. Previously, we introduced the Viral Eukaryotic Bacterial Archaeal (VEBA) open-source software suite to address this critical gap in microbiome research by extending genome-resolved analysis beyond prokaryotes to encompass the understudied realms of eukaryotes and viruses. Here we present VEBA 2.0 with key updates including a comprehensive clustered microeukaryotic protein database, rapid genome/protein-level clustering, bioprospecting, non-coding/organelle gene modeling, genome-resolved taxonomic/pathway profiling, long-read support, and containerization. We demonstrate VEBA's versatile application through the analysis of diverse case studies including marine water, Siberian permafrost, and white-tailed deer lung tissues with the latter showcasing how to identify integrated viruses. VEBA represents a crucial advancement in microbiome research, offering a powerful and accessible software suite that bridges the gap between genomics and biotechnological solutions.
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Affiliation(s)
- Josh L Espinoza
- Department of Environment and Sustainability, J. Craig Venter Institute, La Jolla, CA 92037, USA
- Department of Genomic Medicine and Infectious Diseases, J. Craig Venter Institute, La Jolla, CA 92037, USA
| | - Allan Phillips
- Department of Environment and Sustainability, J. Craig Venter Institute, La Jolla, CA 92037, USA
- Department of Genomic Medicine and Infectious Diseases, J. Craig Venter Institute, La Jolla, CA 92037, USA
| | - Melanie B Prentice
- School of Food and Agriculture, University of Maine, Orono, ME 04469, USA
| | - Gene S Tan
- Department of Genomic Medicine and Infectious Diseases, J. Craig Venter Institute, La Jolla, CA 92037, USA
| | - Pauline L Kamath
- School of Food and Agriculture, University of Maine, Orono, ME 04469, USA
- Maine Center for Genetics in the Environment, University of Maine, Orono, ME 04469, USA
| | - Karen G Lloyd
- Microbiology Department, University of Tennessee, Knoxville, TN 37917, USA
| | - Chris L Dupont
- Department of Environment and Sustainability, J. Craig Venter Institute, La Jolla, CA 92037, USA
- Department of Genomic Medicine and Infectious Diseases, J. Craig Venter Institute, La Jolla, CA 92037, USA
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8
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Sun S, Ma M, Guo J, He X, Yin X, Sun T, Zhang Q, Kang S. Westerlies-driven transboundary transport of atmospheric mercury to the north-central Tibetan Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 932:173135. [PMID: 38734088 DOI: 10.1016/j.scitotenv.2024.173135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 05/07/2024] [Accepted: 05/08/2024] [Indexed: 05/13/2024]
Abstract
The transboundary mercury (Hg) pollution has caused adverse effects on fragile ecosystems of the Tibetan Plateau (TP). Yet, knowledge of transport paths and source regions of atmospheric Hg on the inland TP remains poor. Continuous measurements of atmospheric total gaseous mercury (TGM) were conducted in the central TP (Tanggula station, 5100 m a.s.l., June-October). Atmospheric TGM level at Tanggula station (1.90 ± 0.30 ng m-3) was higher than the background level in the Northern Hemisphere. The identified high-potential source regions of atmospheric TGM were primarily located in the northern South Asia region. TGM concentrations were lower during the Indian summer monsoon (ISM)-dominant period (1.81 ± 0.25 ng m-3) than those of the westerly-receding period (2.18 ± 0.40 ng m-3) and westerly-intensifying period (1.91 ± 0.26 ng m-3), contrary to the seasonal pattern in southern TP. The distinct TGM minima during the ISM-dominant period indicated lesser importance of ISM-transported Hg to Tanggula station located in the northern boundary of ISM intrusion, compared to stations in proximity to South and Southeast Asia source regions. Instead, from the ISM-dominant period to the westerly-intensifying period, TGM concentrations showed an increasing trend as westerlies intensified, indicating the key role of westerlies in transboundary transport of atmospheric Hg to the inland TP.
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Affiliation(s)
- Shiwei Sun
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Key Laboratory of Cryospheric Science and Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, CAS, Lanzhou 730000, China
| | - Ming Ma
- College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Junming Guo
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Key Laboratory of Cryospheric Science and Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, CAS, Lanzhou 730000, China
| | - Xiaobo He
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Tanggula Cryosphere and Environment Observation Station, State Key Laboratory of Cryospheric Science, Lanzhou 730000, China
| | - Xiufeng Yin
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Key Laboratory of Cryospheric Science and Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, CAS, Lanzhou 730000, China
| | - Tao Sun
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, China
| | - Qianggong Zhang
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, CAS, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Key Laboratory of Cryospheric Science and Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, CAS, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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9
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Bottini CLJ, Whiley RE, Branfireun BA, MacDougall-Shackleton SA. Effects of sublethal methylmercury and food stress on songbird energetic performance: metabolic rates, molt and feather quality. J Exp Biol 2024; 227:jeb246239. [PMID: 38856174 PMCID: PMC11418191 DOI: 10.1242/jeb.246239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Accepted: 05/28/2024] [Indexed: 06/11/2024]
Abstract
Organisms regularly adjust their physiology and energy balance in response to predictable seasonal environmental changes. Stressors and contaminants have the potential to disrupt these critical seasonal transitions. No studies have investigated how simultaneous exposure to the ubiquitous toxin methylmercury (MeHg) and food stress affects birds' physiological performance across seasons. We quantified several aspects of energetic performance in song sparrows, Melospiza melodia, exposed or not to unpredictable food stress and MeHg in a 2×2 experimental design, over 3 months during the breeding season, followed by 3 months post-exposure. Birds exposed to food stress had reduced basal metabolic rate and non-significant higher factorial metabolic scope during the exposure period, and had a greater increase in lean mass throughout most of the experimental period. Birds exposed to MeHg had increased molt duration, and increased mass:length ratio of some of their primary feathers. Birds exposed to the combined food stress and MeHg treatment often had responses similar to the stress-only or MeHg-only exposure groups, suggesting these treatments affected physiological performance through different mechanisms and resulted in compensatory or independent effects. Because the MeHg and stress variables were selected in candidate models with a ΔAICc lower than 2 but the 95% confidence interval of these variables overlapped zero, we found weak support for MeHg effects on all measures except basal metabolic rate, and for food stress effects on maximum metabolic rate, factorial metabolic scope and feather mass:length ratio. This suggests that MeHg and food stress effects on these measures are statistically identified but not simple and/or were too weak to be detected via linear regression. Overall, combined exposure to ecologically relevant MeHg and unpredictable food stress during the breeding season does not appear to induce extra energetic costs for songbirds in the post-exposure period. However, MeHg effects on molt duration could carry over across multiple annual cycle stages.
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Affiliation(s)
- Claire L. J. Bottini
- The University of Western Ontario, Department of Biology, 1151 Richmond St., London, ON, Canada, N6A 5B7
- Advanced Facility for Avian Research, University of Western Ontario, London, ON, N6G 4W4, Canada
| | - Rebecca E. Whiley
- The University of Western Ontario, Department of Biology, 1151 Richmond St., London, ON, Canada, N6A 5B7
- Advanced Facility for Avian Research, University of Western Ontario, London, ON, N6G 4W4, Canada
| | - Brian A. Branfireun
- The University of Western Ontario, Department of Biology, 1151 Richmond St., London, ON, Canada, N6A 5B7
- Advanced Facility for Avian Research, University of Western Ontario, London, ON, N6G 4W4, Canada
| | - Scott A. MacDougall-Shackleton
- Advanced Facility for Avian Research, University of Western Ontario, London, ON, N6G 4W4, Canada
- The University of Western Ontario, Department of Psychology, 1151 Richmond St., London, ON, N6A 5C2, Canada
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10
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Yuan T, Huang S, Zhang P, Song Z, Ge J, Miao X, Wang Y, Pang Q, Peng D, Wu P, Shao J, Zhang P, Wang Y, Guo H, Guo W, Zhang Y. Potential decoupling of CO 2 and Hg uptake process by global vegetation in the 21st century. Nat Commun 2024; 15:4490. [PMID: 38802424 PMCID: PMC11130250 DOI: 10.1038/s41467-024-48849-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 05/15/2024] [Indexed: 05/29/2024] Open
Abstract
Mercury (Hg), a potent neurotoxin posing risks to human health, is cycled through vegetation uptake, which is susceptible to climate change impacts. However, the extent and pattern of these impacts are largely unknown, obstructing predictions of Hg's fate in terrestrial ecosystems. Here, we evaluate the effects of climate change on vegetation elemental Hg [Hg(0)] uptake using a state-of-the-art global terrestrial Hg model (CLM5-Hg) that incorporates plant physiology. In a business-as-usual scenario, the terrestrial Hg(0) sink is predicted to decrease by 1870 Mg yr-1 in 2100, that is ~60% lower than the present-day condition. We find a potential decoupling between the trends of CO2 assimilation and Hg(0) uptake process by vegetation in the 21st century, caused by the decreased stomatal conductance with increasing CO2. This implies a substantial influx of Hg into aquatic ecosystems, posing an elevated threat that warrants consideration during the evaluation of the effectiveness of the Minamata Convention.
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Affiliation(s)
- Tengfei Yuan
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu, China
| | - Shaojian Huang
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu, China
| | - Peng Zhang
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu, China
| | - Zhengcheng Song
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu, China
- Frontiers Science Center for Critical Earth Material Cycling, Nanjing University, Nanjing, Jiangsu, China
- Joint International Research Laboratory of Atmospheric and Earth System Sciences, Nanjing University, Nanjing, Nanjing, Jiangsu, China
| | - Jun Ge
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu, China
- Joint International Research Laboratory of Atmospheric and Earth System Sciences, Nanjing University, Nanjing, Nanjing, Jiangsu, China
| | - Xin Miao
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu, China
| | - Yujuan Wang
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu, China
| | - Qiaotong Pang
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu, China
| | - Dong Peng
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu, China
| | - Peipei Wu
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu, China
| | - Junjiong Shao
- State Key Laboratory of Subtropical Silviculture, College of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, China
| | - Peipei Zhang
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Yabo Wang
- College of Environmental Science and Engineering, Yangzhou University, Yangzhou, China
| | - Hongyan Guo
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, China
| | - Weidong Guo
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu, China
| | - Yanxu Zhang
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu, China.
- Frontiers Science Center for Critical Earth Material Cycling, Nanjing University, Nanjing, Jiangsu, China.
- Joint International Research Laboratory of Atmospheric and Earth System Sciences, Nanjing University, Nanjing, Nanjing, Jiangsu, China.
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11
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Hong Q, Xu H, Sun X, Li J, Huang W, Qu Z, Zhang L, Yan N. In-situ low-temperature sulfur CVD on metal sulfides with SO 2 to realize self-sustained adsorption of mercury. Nat Commun 2024; 15:3362. [PMID: 38637534 PMCID: PMC11026451 DOI: 10.1038/s41467-024-47725-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Accepted: 04/11/2024] [Indexed: 04/20/2024] Open
Abstract
Capturing gaseous mercury (Hg0) from sulfur dioxide (SO2)-containing flue gases remains a common yet persistently challenge. Here we introduce a low-temperature sulfur chemical vapor deposition (S-CVD) technique that effectively converts SO2, with intermittently introduced H2S, into deposited sulfur (Sd0) on metal sulfides (MS), facilitating self-sustained adsorption of Hg0. ZnS, as a representative MS model, undergoes a decrease in the coordination number of Zn-S from 3.9 to 3.5 after Sd0 deposition, accompanied by the generation of unsaturated-coordinated polysulfide species (Sn2-, named Sd*) with significantly enhanced Hg0 adsorption performance. Surprisingly, the adsorption product, HgS (ZnS@HgS), can serve as a fresh interface for the activation of Sd0 to Sd* through the S-CVD method, thereby achieving a self-sustained Hg0 adsorption capacity exceeding 300 mg g-1 without saturation limitations. Theoretical calculations substantiate the self-sustained adsorption mechanism that S8 ring on both ZnS and ZnS@HgS can be activated to chemical bond S4 chain, exhibiting a stronger Hg0 adsorption energy than pristine ones. Importantly, this S-CVD strategy is applicable to the in-situ activation of synthetic or natural MS containing chalcophile metal elements for Hg0 removal and also holds potential applications for various purposes requiring MS adsorbents.
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Affiliation(s)
- Qinyuan Hong
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Haomiao Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Xiaoming Sun
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Jiaxing Li
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Wenjun Huang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Zan Qu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.
| | - Lizhi Zhang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education Institute of Applied & Environmental Chemistry College of Chemistry, Central China Normal University, Wuhan, 430079, China
| | - Naiqiang Yan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.
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12
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Espinoza JL, Phillips A, Prentice MB, Tan GS, Kamath PL, Lloyd KG, Dupont CL. Unveiling the Microbial Realm with VEBA 2.0: A modular bioinformatics suite for end-to-end genome-resolved prokaryotic, (micro)eukaryotic, and viral multi-omics from either short- or long-read sequencing. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.08.583560. [PMID: 38559265 PMCID: PMC10979853 DOI: 10.1101/2024.03.08.583560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The microbiome is a complex community of microorganisms, encompassing prokaryotic (bacterial and archaeal), eukaryotic, and viral entities. This microbial ensemble plays a pivotal role in influencing the health and productivity of diverse ecosystems while shaping the web of life. However, many software suites developed to study microbiomes analyze only the prokaryotic community and provide limited to no support for viruses and microeukaryotes. Previously, we introduced the Viral Eukaryotic Bacterial Archaeal (VEBA) open-source software suite to address this critical gap in microbiome research by extending genome-resolved analysis beyond prokaryotes to encompass the understudied realms of eukaryotes and viruses. Here we present VEBA 2.0 with key updates including a comprehensive clustered microeukaryotic protein database, rapid genome/protein-level clustering, bioprospecting, non-coding/organelle gene modeling, genome-resolved taxonomic/pathway profiling, long-read support, and containerization. We demonstrate VEBA's versatile application through the analysis of diverse case studies including marine water, Siberian permafrost, and white-tailed deer lung tissues with the latter showcasing how to identify integrated viruses. VEBA represents a crucial advancement in microbiome research, offering a powerful and accessible platform that bridges the gap between genomics and biotechnological solutions.
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Affiliation(s)
- Josh L. Espinoza
- Department of Environment and Sustainability, J. Craig Venter Institute, La Jolla, CA 92037, USA
- Department of Genomic Medicine and Infectious Diseases, J. Craig Venter Institute, La Jolla, CA 92037, USA
| | - Allan Phillips
- Department of Environment and Sustainability, J. Craig Venter Institute, La Jolla, CA 92037, USA
- Department of Genomic Medicine and Infectious Diseases, J. Craig Venter Institute, La Jolla, CA 92037, USA
| | | | - Gene S. Tan
- Department of Genomic Medicine and Infectious Diseases, J. Craig Venter Institute, La Jolla, CA 92037, USA
| | - Pauline L. Kamath
- School of Food and Agriculture, University of Maine, Orono, ME 04469, USA
| | - Karen G. Lloyd
- Microbiology Department, University of Tennessee, Knoxville, TN 37917, USA
| | - Chris L. Dupont
- Department of Environment and Sustainability, J. Craig Venter Institute, La Jolla, CA 92037, USA
- Department of Genomic Medicine and Infectious Diseases, J. Craig Venter Institute, La Jolla, CA 92037, USA
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13
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Feinberg A, Jiskra M, Borrelli P, Biswakarma J, Selin NE. Deforestation as an Anthropogenic Driver of Mercury Pollution. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024. [PMID: 38328901 DOI: 10.1021/acs.est.3c07851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Deforestation reduces the capacity of the terrestrial biosphere to take up toxic pollutant mercury (Hg) and enhances the release of secondary Hg from soils. The consequences of deforestation for Hg cycling are not currently considered by anthropogenic emission inventories or specifically addressed under the global Minamata Convention on Mercury. Using global Hg modeling constrained by field observations, we estimate that net Hg fluxes to the atmosphere due to deforestation are 217 Mg year-1 (95% confidence interval (CI): 134-1650 Mg year-1) for 2015, approximately 10% of global primary anthropogenic emissions. If deforestation of the Amazon rainforest continues at business-as-usual rates, net Hg emissions from the region will increase by 153 Mg year-1 by 2050 (CI: 97-418 Mg year-1), enhancing the transport and subsequent deposition of Hg to aquatic ecosystems. Substantial Hg emissions reductions are found for two potential cases of land use policies: conservation of the Amazon rainforest (92 Mg year-1, 95% CI: 59-234 Mg year-1) and global reforestation (98 Mg year-1, 95% CI: 64-449 Mg year-1). We conclude that deforestation-related emissions should be incorporated as an anthropogenic source in Hg inventories and that land use policy could be leveraged to address global Hg pollution.
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Affiliation(s)
- Aryeh Feinberg
- Institute for Data, Systems, and Society, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Martin Jiskra
- Environmental Geosciences, University of Basel, Basel 4056, Switzerland
| | | | - Jagannath Biswakarma
- Environmental Geosciences, University of Basel, Basel 4056, Switzerland
- Department of Water Resources and Drinking Water, Eawag, Dübendorf 8600, Switzerland
| | - Noelle E Selin
- Institute for Data, Systems, and Society, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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14
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Andersson Stavridis M, Røed SB, Hansen BB, Mikkelsen Ø, Ciesielski TM, Jenssen BM. Tracing the footprints of Arctic pollution: Spatial variations in toxic and essential elements in Svalbard reindeer (Rangifer tarandus platyrhynchus) faeces. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167562. [PMID: 37802349 DOI: 10.1016/j.scitotenv.2023.167562] [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: 08/11/2023] [Revised: 09/29/2023] [Accepted: 10/01/2023] [Indexed: 10/08/2023]
Abstract
The Arctic is an accumulation zone of long-range transported pollution. In addition, local anthropogenic activities further contribute to regional pollution levels. The Svalbard reindeer (Rangifer tarandus platyrhynchus) is a suitable organism for studying and monitoring exposure to anthropogenic pollutants at the base of the terrestrial Arctic food web, and reindeer faeces have been promoted as non-invasive means of biomonitoring contaminant exposure. This study used HR-ICP-MS to analyse levels and composition of 16 elements in Svalbard reindeer faeces (n = 96) and soil (n = 9) from two locations on Svalbard, with the aim to assess whether local anthropogenic pollution influences element bioavailability. One of the sampling areas, the Nordenskiöld coast, is situated on the west coast of Spitsbergen, close to the Arctic Ocean and relatively far from local anthropogenic sources. The other sampling area, Adventdalen, is located further inland and close to Longyearbyen, the largest settlement of the archipelago. There was a significant difference in faecal elemental concentration and composition between the Adventdalen and Nordenskiöld coast reindeer populations. Elements of geogenic origin (e.g., Al, Cu and Fe) were found at higher levels in faeces from Adventdalen. In comparison, levels of Ca, Se and the toxic elements Cd and Pb were higher in faecal samples from the Nordenskiöld coast. The significantly higher levels of faecal Cd and Pb at Nordenskiöld coast may be due to marine input, dietary differences between the populations, or possible anthropogenic influence from the nearby settlement of Barentsburg. There was, however, a decoupling in elemental composition between faecal and soil samples, which may derive from a selective vegetational uptake of elements from the soil. The results suggest that reindeer are exposed to a range of elements and that faeces can be used to monitor the exposure to bioavailable environmental levels of both essential and toxic elements in terrestrial ecosystems.
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Affiliation(s)
- Malin Andersson Stavridis
- Department of Arctic Technology, University Centre in Svalbard (UNIS), P.O. Box 156, N-9171 Longyearbyen, Norway; Department of Biology, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway.
| | - Susanne Brix Røed
- Department of Biology, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
| | - Brage Bremset Hansen
- Department of Biology, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway; Department of Terrestrial Ecology, Norwegian Institute for Nature Research (NINA), NO-7485 Trondheim, Norway
| | - Øyvind Mikkelsen
- Department of Arctic Technology, University Centre in Svalbard (UNIS), P.O. Box 156, N-9171 Longyearbyen, Norway; Department of Chemistry, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
| | - Tomasz Maciej Ciesielski
- Department of Arctic Technology, University Centre in Svalbard (UNIS), P.O. Box 156, N-9171 Longyearbyen, Norway; Department of Biology, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
| | - Bjørn Munro Jenssen
- Department of Arctic Technology, University Centre in Svalbard (UNIS), P.O. Box 156, N-9171 Longyearbyen, Norway; Department of Biology, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway.
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15
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Cai X, Fan Y, Hong Q, Liu Z, Qu Z, Yan N, Xu H. Unveiling the Halogenation-Induced Formation of Hg 3Se 2X 2 (X = Cl, Br, and I) Compounds for Multiphase Mercury Cycling. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:20431-20439. [PMID: 37992298 DOI: 10.1021/acs.est.3c08021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2023]
Abstract
The interaction between mercury (Hg) and inorganic compounds, including selenium (Se), sulfur (S), and halogens (X = Cl, Br, or I), plays a critical role in the global mercury cycle. However, most previously reported mercury compounds are susceptible to reduction, leading to the release of elemental mercury (Hg0) and causing secondary pollution. In this study, we unveil a groundbreaking discovery that underscores the vital role of halogenation in creating exceptionally stable Hg3Se2X2 compounds. Through the dynamic interplay of Hg, Se, and halogens, an intermediary stage denoted [HgSe]m[HgX2]n emerges, and this transformative process significantly elevates the stabilization of mercury. Remarkably, halogen ions strategically occupy pores at the periphery of HgSe clusters, engendering a more densely packed atomic arrangement of Hg, Se, and halogen components. A marked enhancement in both thermal and acid stability is observed, wherein temperatures ascend from 130 to 300 °C (transitioning from HgSe to Hg3Se2Cl2). This sequence of escalating stability follows the order HgSe < Hg3Se2I2 < Hg3Se2Br2 < Hg3Se2Cl2 for thermal resilience, complemented by virtually absent acid leaching. This innovative compound formation fundamentally alters the transformation pathways of gaseous Hg0 and ionic mercury (Hg2+), resulting in highly efficient in situ removal of both Hg0 and Hg2+ ions. These findings pave the way for groundbreaking advancements in mercury stabilization and environmental remediation strategies, offering a comprehensive solution through the creation of chemically stable precipitates.
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Affiliation(s)
- Xiangling Cai
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yurui Fan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Qinyuan Hong
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Zhisong Liu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Zan Qu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Naiqiang Yan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Haomiao Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
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16
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Burke S, Muir DCG, Kirk J, Barst BD, Iqaluk D, Wang X, Pope M, Lamoureux SF, Lafrenière MJ. Divergent Temporal Trends of Mercury in Arctic Char from Paired Lakes Influenced by Climate-Related Drivers. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2023; 42:2712-2725. [PMID: 37712511 DOI: 10.1002/etc.5744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/03/2023] [Accepted: 09/01/2023] [Indexed: 09/16/2023]
Abstract
Climate-driven changes including rising air temperatures, enhanced permafrost degradation, and altered precipitation patterns can have profound effects on contaminants, such as mercury (Hg), in High Arctic lakes. Two physically similar lakes, East Lake and West Lake at the Cape Bounty Arctic Watershed Observatory on Melville Island, Nunavut, Canada are being affected by climate change differently. Both lakes have experienced permafrost degradation in their catchments; however, West Lake has also undergone multiple underwater Mass Movement Events (MMEs; beginning in fall 2008), leading to a sustained 50-fold increase in turbidity. This provided the unique opportunity to understand the potential impacts of permafrost degradation and other climate-related effects on Hg concentrations and body condition of landlocked Arctic char (Salvelinus alpinus), an important sentinel species across the Circum-Arctic. Our objectives were to assess temporal trends in char Hg concentrations and to determine potential mechanisms driving the trends. There was a significant decrease in Hg concentrations in East Lake char, averaging 6.5%/year and 3.8%/year for length-adjusted and age-adjusted means, respectively, from 2008 to 2019. Conversely, in West Lake there was a significant increase, averaging 7.9%/year and 8.0%/year for length-adjusted and age-adjusted mean Hg concentrations, respectively, for 2009 to 2017 (the last year with sufficient sample size). The best predictors of length-adjusted Hg concentrations in West Lake were carbon and nitrogen stable isotope ratios, indicating a shift in diet including possible dietary starvation brought on by the profound increase in lake turbidity. Our study provides an example of how increasing lake turbidity, a likely consequence of climate warming in Arctic lakes, may influence fish condition and Hg concentrations. Environ Toxicol Chem 2023;42:2712-2725. © 2023 His Majesty the King in Right of Canada and The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Environment and Climate Change Canada.
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Affiliation(s)
- Samantha Burke
- Minnow Environmental, Guelph, Ontario, Canada
- Aquatic Contaminants Research Division, Environment & Climate Change Canada, Burlington, Ontario, Canada
| | - Derek C G Muir
- Aquatic Contaminants Research Division, Environment & Climate Change Canada, Burlington, Ontario, Canada
- School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Jane Kirk
- Aquatic Contaminants Research Division, Environment & Climate Change Canada, Burlington, Ontario, Canada
| | - Benjamin D Barst
- Water and Environmental Research Center, University of Alaska Fairbanks, Fairbanks, Alaska, USA
| | - Debbie Iqaluk
- Water and Environmental Research Center, University of Alaska Fairbanks, Fairbanks, Alaska, USA
| | - Xiaowa Wang
- Aquatic Contaminants Research Division, Environment & Climate Change Canada, Burlington, Ontario, Canada
| | - Mike Pope
- Department of Geography and Planning, Queen's University, Kingston, Ontario, Canada
| | - Scott F Lamoureux
- Department of Geography and Planning, Queen's University, Kingston, Ontario, Canada
| | - Melissa J Lafrenière
- Department of Geography and Planning, Queen's University, Kingston, Ontario, Canada
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17
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Staniszewska KJ, Reyes AV, Cooke CA. Glacial Erosion Drives High Summer Mercury Exports from the Yukon River, Canada. ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS 2023; 10:1117-1124. [PMID: 38025955 PMCID: PMC10653217 DOI: 10.1021/acs.estlett.3c00427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 09/29/2023] [Accepted: 10/02/2023] [Indexed: 12/01/2023]
Abstract
Mercury concentrations and yields in the Yukon River are the highest of the world's six largest panarctic drainages. Permafrost thaw has been implicated as the main driver of these high values. Alternative sources include mercury released from glacial melt and erosion, atmospheric mercury pollution, or surface mining. To determine the summer source and speciation of mercury across the Yukon River basin within Canada, we sampled water from 12 tributaries and the mainstem during July 2021. The total (unfiltered) mercury concentration in the glacier-fed White River was 57 ng/L, >10 times higher than all other sampled tributaries. The White River's high total mercury concentrations were driven by suspended sediment and persisted ∼300 km downstream of glacierized headwaters. Total mercury concentrations were lowest (typically <2 ng/L) in tributaries downstream of still-water landscape features (e.g., lakes and settling ponds), suggesting these features are effective sinks for sediment-bound mercury. Low total mercury concentrations (∼2 ng/L) were also observed in five tributaries across diverse thawing permafrost landscapes. These results suggest that glacial erosion and meltwater transport, not permafrost, drive enhanced exports of mercury with suspended sediment. Mercury exports may decline as glacial watersheds pass peak water. Other factors, including mercury released from permafrost thaw, are minor components at present.
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Affiliation(s)
- Kasia J. Staniszewska
- Department
of Earth and Atmospheric Sciences, University
of Alberta, Edmonton, Alberta T6G 2E3, Canada
| | - Alberto V. Reyes
- Department
of Earth and Atmospheric Sciences, University
of Alberta, Edmonton, Alberta T6G 2E3, Canada
| | - Colin A. Cooke
- Department
of Earth and Atmospheric Sciences, University
of Alberta, Edmonton, Alberta T6G 2E3, Canada
- Environment
and Protected Areas, Government of Alberta, Edmonton, Alberta T5K 2G6, Canada
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18
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Wenwen Z, Yuan X, Zhongsheng Z, Xuehui Z, Haitao W. Accelerated Hg loss and increased methylmercury covary with soil organic matter mineralization and dissolved organic matter humification under warming conditions in permafrost marsh, Northeast China. ENVIRONMENTAL RESEARCH 2023; 234:116593. [PMID: 37423359 DOI: 10.1016/j.envres.2023.116593] [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: 05/24/2023] [Revised: 07/06/2023] [Accepted: 07/06/2023] [Indexed: 07/11/2023]
Abstract
Currently, little is available on how mercury (Hg) methylation couples with soil organic matter decomposition in degraded permafrost in high northern latitudes, where the climate is becoming warmer rapidly. Here, we revealed the complex interactions between soil organic matter (SOM) mineralization, dissolved organic matter (DOM) and methylmercury (MeHg) production based on an 87-day anoxic warming incubation experiment. Results supported remarkably promotion effects of warming on MeHg production, by 130%-205% on average. Total mercury (THg) loss under warming treatment depended on marsh types but showed an increasing trend on the whole. Warming yielded higher proportions of MeHg to THg (%MeHg), increased by 123%-569%. As expected, greenhouse gas emission was significantly enhanced by warming. Warming also strengthened fluorescence intensities of fulvic-like and protein-like DOM, with contributions to total fluorescence intensities of 49%-92% and 8%-51%, respectively. DOM and its spectral features explained 60% variation of MeHg, and the explanation increased to 82% in conjunction with greenhouse gas emissions. The structural equation model implied that warming, greenhouse gas emission, and humification of DOM had positive effects on Hg methylation potential, while microbial-derived DOM showed negative effects on MeHg. These results showed that accelerated Hg loss and increased methylation covaried with greenhouse gas emission and DOM formation under warming conditions in permafrost marsh.
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Affiliation(s)
- Zhao Wenwen
- State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xin Yuan
- State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhang Zhongsheng
- State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China.
| | - Zhang Xuehui
- State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China; Beijing Normal University, Beijing, 136000, China
| | - Wu Haitao
- State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China
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19
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Gundersen CB, Yakushev E, Terentjev P, Kashulin N, Korobov V, Frolova N, Romanov A, Jermilova U, Lokhov A, Miskevich I, Kotova E, Steindal EH, Veiteberg Braaten HF. Mercury in the Barents region - River fluxes, sources, and environmental concentrations. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 333:122055. [PMID: 37356792 DOI: 10.1016/j.envpol.2023.122055] [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: 02/16/2023] [Revised: 06/02/2023] [Accepted: 06/14/2023] [Indexed: 06/27/2023]
Abstract
Arctic rivers are receiving increased attention for their contributing of mercury (Hg) to the Arctic Ocean. Despite this, the knowledge on both the terrestrial release sources and the levels of Hg in the rivers are limited. Within the Arctic, the Barents region has a high industrial development, including multiple potential Hg release sources. This study presents the first overview of potential Hg release sources on Norwegian and Russian mainland draining to the Barents Sea. Source categories cover mining and metallurgy industry; historical pulp and paper production; municipal and industrial solid waste handling; fossil fuel combustion; and past military activities. Available data on Hg in freshwater bodies near the identified potential release sources are reviewed. Levels of Hg were occasionally exceeding the national pollution control limits, thereby posing concern to the local human population and wildlife. However, the studies were sparse and often unsystematic. Finally, we present new data of Hg measured in five Barents rivers. These data reveal strong seasonality in the Hg levels, with a total annual flux constituting 2% of the panarctic total. With this new insight we aspire to contribute to the international efforts of reducing Hg pollution, such as through the effective implementation of the Minamata Convention. Future studies documenting Hg in exposed Barents freshwater bodies are warranted.
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Affiliation(s)
| | - Evgeniy Yakushev
- Norwegian Institute for Water Research (NIVA), Økernveien 94, 0579, Oslo, Norway; Shirshov Institute of Oceanology, Russian Academy of Sciences (IORAS), 36, Nakhimovskiy Prospect, Moscow, 117997, Russia
| | - Petr Terentjev
- Institute of North Industrial Ecology Problems (INEP), Akademgorodok, d. 14A, Apatity, Murmansk Region, 184209, Russia
| | - Nikolai Kashulin
- Institute of North Industrial Ecology Problems (INEP), Akademgorodok, d. 14A, Apatity, Murmansk Region, 184209, Russia
| | - Vladimir Korobov
- Shirshov Institute of Oceanology, Russian Academy of Sciences (IORAS), 36, Nakhimovskiy Prospect, Moscow, 117997, Russia
| | - Natalia Frolova
- Lomonosov Moscow State University (MSU), GSP-1, Leninskie Gory, Moscow, 119991, Russia
| | - Alexander Romanov
- Scientific Research Institute for Atmospheric Air Protection (SRI Atmosphere JSC), 7, Karbyshev st., St. Petersburg, 194021, Russia
| | - Una Jermilova
- Trent University, 1600 West Bank Dr., Peterborough, ON K9L 0G2, Canada
| | - Alexey Lokhov
- Shirshov Institute of Oceanology, Russian Academy of Sciences (IORAS), 36, Nakhimovskiy Prospect, Moscow, 117997, Russia
| | - Igor Miskevich
- Shirshov Institute of Oceanology, Russian Academy of Sciences (IORAS), 36, Nakhimovskiy Prospect, Moscow, 117997, Russia
| | - Ekaterina Kotova
- Shirshov Institute of Oceanology, Russian Academy of Sciences (IORAS), 36, Nakhimovskiy Prospect, Moscow, 117997, Russia
| | - Eirik Hovland Steindal
- Norwegian Institute for Water Research (NIVA), Økernveien 94, 0579, Oslo, Norway; Norwegian University of Life Sciences (NMBU), Universitetstunet 3, 1432 Ås, Norway
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20
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Pan S, Guo Z, Dai H, Zhang H, Zeng Z, Wang M. Assessment of the water quality and toxicity effects on zebrafish (Danio rerio) of a stream near a phosphorus chemical plant in Guizhou Province, southwestern China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:94205-94217. [PMID: 37526819 DOI: 10.1007/s11356-023-28850-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 07/14/2023] [Indexed: 08/02/2023]
Abstract
To reveal the influence of the phosphorus chemical industry (PCI) on regional water environmental quality and safety, the water quality and ecotoxicological effects of a stream near a phosphorus chemical plant (PCP) in Guizhou Province, southwestern China, were investigated based on water samples collected from the stream. The results showed that the average concentrations of NH3-N, TN, P, F-, Hg, Mn, and Ni were 3.14 mg/L, 30.09 mg/L, 3.34 mg/L, 1.18 mg/L, 1.06 μg/L, 45.82 μg/L, and 11.30 μg/L, respectively. The overall water quality of the stream was in the heavily polluted category, and NH3-N, TN, P, F-, and Hg were the main pollution factors. The degree of pollution was in the order of rainy period > transitional period > dry period, and the most polluted sample site was 1100 m from the PCP. After 28 days of exposure to stream water, there was no significant change in the growth parameters of zebrafish. The gills of zebrafish showed a small amount of epithelial cell detachment and a small amount of inflammatory cell infiltration, and the liver tissue displayed a large amount of hepatocyte degeneration with loose and lightly stained cytoplasm. Compared with the control group, the %DNA in tail, tail length, tail moment, and olive tail moment were significantly increased (p < 0.05), indicating that the water sample caused DNA damage in the peripheral blood erythrocytes of zebrafish. The stream water in the PCI area was found to be polluted and exhibited significant toxicity to zebrafish, which could pose a threat to regional ecological security.
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Affiliation(s)
- Sha Pan
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China.
| | - Ziyu Guo
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Hengmei Dai
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Hua Zhang
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Zhidong Zeng
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Min Wang
- School of Public Health, The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
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21
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Sonke JE, Angot H, Zhang Y, Poulain A, Björn E, Schartup A. Global change effects on biogeochemical mercury cycling. AMBIO 2023; 52:853-876. [PMID: 36988895 PMCID: PMC10073400 DOI: 10.1007/s13280-023-01855-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 02/07/2023] [Accepted: 03/03/2023] [Indexed: 06/18/2023]
Abstract
Past and present anthropogenic mercury (Hg) release to ecosystems causes neurotoxicity and cardiovascular disease in humans with an estimated economic cost of $117 billion USD annually. Humans are primarily exposed to Hg via the consumption of contaminated freshwater and marine fish. The UNEP Minamata Convention on Hg aims to curb Hg release to the environment and is accompanied by global Hg monitoring efforts to track its success. The biogeochemical Hg cycle is a complex cascade of release, dispersal, transformation and bio-uptake processes that link Hg sources to Hg exposure. Global change interacts with the Hg cycle by impacting the physical, biogeochemical and ecological factors that control these processes. In this review we examine how global change such as biome shifts, deforestation, permafrost thaw or ocean stratification will alter Hg cycling and exposure. Based on past declines in Hg release and environmental levels, we expect that future policy impacts should be distinguishable from global change effects at the regional and global scales.
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Affiliation(s)
- Jeroen E. Sonke
- Géosciences Environnement Toulouse, CNRS/IRD, Université Paul Sabatier Toulouse 3, 14 ave Edouard Belin, 31400 Toulouse, France
| | - Hélène Angot
- Univ. Grenoble Alpes, CNRS, INRAE, IRD, Grenoble INP, IGE, 1025 rue de la piscine, 38000 Grenoble, France
| | - Yanxu Zhang
- School of Atmospheric Sciences, Nanjing University, 163 Xianlin Road, Nanjing, 210023 Jiangsu China
| | - Alexandre Poulain
- Department of Biology, University of Ottawa, Ottawa, ON K1N6N5 Canada
| | - Erik Björn
- Department of Chemistry, Umeå University, 90187 Umeå, Sweden
| | - Amina Schartup
- Geosciences Research Division, Scripps Institution of Oceanography, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093 USA
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22
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Wu X, Almatari AL, Cyr WA, Williams DE, Pfiffner SM, Rivkina EM, Lloyd KG, Vishnivetskaya TA. Microbial life in 25-m-deep boreholes in ancient permafrost illuminated by metagenomics. ENVIRONMENTAL MICROBIOME 2023; 18:33. [PMID: 37055869 PMCID: PMC10103415 DOI: 10.1186/s40793-023-00487-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 03/24/2023] [Indexed: 06/19/2023]
Abstract
This study describes the composition and potential metabolic adaptation of microbial communities in northeastern Siberia, a repository of the oldest permafrost in the Northern Hemisphere. Samples of contrasting depth (1.75 to 25.1 m below surface), age (from ~ 10 kyr to 1.1 Myr) and salinity (from low 0.1-0.2 ppt and brackish 0.3-1.3 ppt to saline 6.1 ppt) were collected from freshwater permafrost (FP) of borehole AL1_15 on the Alazeya River, and coastal brackish permafrost (BP) overlying marine permafrost (MP) of borehole CH1_17 on the East Siberian Sea coast. To avoid the limited view provided with culturing work, we used 16S rRNA gene sequencing to show that the biodiversity decreased dramatically with permafrost age. Nonmetric multidimensional scaling (NMDS) analysis placed the samples into three groups: FP and BP together (10-100 kyr old), MP (105-120 kyr old), and FP (> 900 kyr old). Younger FP/BP deposits were distinguished by the presence of Acidobacteriota, Bacteroidota, Chloroflexota_A, and Gemmatimonadota, older FP deposits had a higher proportion of Gammaproteobacteria, and older MP deposits had much more uncultured groups within Asgardarchaeota, Crenarchaeota, Chloroflexota, Patescibacteria, and unassigned archaea. The 60 recovered metagenome-assembled genomes and un-binned metagenomic assemblies suggested that despite the large taxonomic differences between samples, they all had a wide range of taxa capable of fermentation coupled to nitrate utilization, with the exception of sulfur reduction present only in old MP deposits.
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Affiliation(s)
- Xiaofen Wu
- Center for Environmental Biotechnology, University of Tennessee, 1416 Circle Drive, Knoxville, TN, 37996-1605, USA
| | - Abraham L Almatari
- Center for Environmental Biotechnology, University of Tennessee, 1416 Circle Drive, Knoxville, TN, 37996-1605, USA
| | - Wyatt A Cyr
- Center for Environmental Biotechnology, University of Tennessee, 1416 Circle Drive, Knoxville, TN, 37996-1605, USA
| | - Daniel E Williams
- Center for Environmental Biotechnology, University of Tennessee, 1416 Circle Drive, Knoxville, TN, 37996-1605, USA
| | - Susan M Pfiffner
- Center for Environmental Biotechnology, University of Tennessee, 1416 Circle Drive, Knoxville, TN, 37996-1605, USA
| | - Elizaveta M Rivkina
- Soil Cryology Laboratory, Institute of Physicochemical and Biological Problems in Soil Science, Russian Academy of Sciences, Pushchino, Russia, 142290
| | - Karen G Lloyd
- Department of Microbiology, University of Tennessee, Knoxville, TN, 37996, USA
| | - Tatiana A Vishnivetskaya
- Center for Environmental Biotechnology, University of Tennessee, 1416 Circle Drive, Knoxville, TN, 37996-1605, USA.
- Soil Cryology Laboratory, Institute of Physicochemical and Biological Problems in Soil Science, Russian Academy of Sciences, Pushchino, Russia, 142290.
- Department of Microbiology, University of Tennessee, Knoxville, TN, 37996, USA.
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23
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Zhang L, Yin Y, Sun Y, Liang X, Graham DE, Pierce EM, Löffler FE, Gu B. Inhibition of Methylmercury and Methane Formation by Nitrous Oxide in Arctic Tundra Soil Microcosms. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:5655-5665. [PMID: 36976621 PMCID: PMC10100821 DOI: 10.1021/acs.est.2c09457] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 03/03/2023] [Accepted: 03/16/2023] [Indexed: 06/18/2023]
Abstract
Climate warming causes permafrost thaw predicted to increase toxic methylmercury (MeHg) and greenhouse gas [i.e., methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O)] formation. A microcosm incubation study with Arctic tundra soil over 145 days demonstrates that N2O at 0.1 and 1 mM markedly inhibited microbial MeHg formation, methanogenesis, and sulfate reduction, while it slightly promoted CO2 production. Microbial community analyses indicate that N2O decreased the relative abundances of methanogenic archaea and microbial clades implicated in sulfate reduction and MeHg formation. Following depletion of N2O, both MeHg formation and sulfate reduction rapidly resumed, whereas CH4 production remained low, suggesting that N2O affected susceptible microbial guilds differently. MeHg formation strongly coincided with sulfate reduction, supporting prior reports linking sulfate-reducing bacteria to MeHg formation in the Arctic soil. This research highlights complex biogeochemical interactions in governing MeHg and CH4 formation and lays the foundation for future mechanistic studies for improved predictive understanding of MeHg and greenhouse gas fluxes from thawing permafrost ecosystems.
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Affiliation(s)
- Lijie Zhang
- Environmental
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department
of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, United States
| | - Yongchao Yin
- Biosciences
Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Center
for Environmental Biotechnology, University
of Tennessee, Knoxville, Tennessee 37996, United States
- Department
of Microbiology, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Yanchen Sun
- Center
for Environmental Biotechnology, University
of Tennessee, Knoxville, Tennessee 37996, United States
- Department
of Civil and Environmental Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Xujun Liang
- Environmental
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - David E. Graham
- Biosciences
Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Eric M. Pierce
- Environmental
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Frank E. Löffler
- Biosciences
Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Center
for Environmental Biotechnology, University
of Tennessee, Knoxville, Tennessee 37996, United States
- Department
of Microbiology, University of Tennessee, Knoxville, Tennessee 37996, United States
- Department
of Civil and Environmental Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
- Department
of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Baohua Gu
- Environmental
Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department
of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, Tennessee 37996, United States
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24
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Yuan T, Zhang P, Song Z, Huang S, Wang X, Zhang Y. Buffering effect of global vegetation on the air-land exchange of mercury: Insights from a novel terrestrial mercury model based on CESM2-CLM5. ENVIRONMENT INTERNATIONAL 2023; 174:107904. [PMID: 37012193 DOI: 10.1016/j.envint.2023.107904] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 03/04/2023] [Accepted: 03/26/2023] [Indexed: 06/19/2023]
Abstract
The vegetation uptake of atmospheric elemental mercury [Hg(0)] and its subsequent littering are critical processes of the terrestrial Hg cycles. There is a large uncertainty in the estimated global fluxes of these processes due to the knowledge gap in the underlying mechanisms and their relationship with environmental factors. Here, we develop a new global model based on the Community Land Model Version 5 (CLM5-Hg) as an independent component of the Community Earth System Model 2 (CESM2). We explore the global pattern of gaseous elemental Hg [Hg(0)] uptake by vegetation and the spatial distribution of litter Hg concentration constrained by observed datasets as well as its driving mechanism. The annual vegetation uptake of Hg(0) is estimated as 3132 Mg yr-1, which is considerably higher than previous global models. The scheme of dynamic plant growth including stomatal activities substantially improves the estimation for global terrestrial distribution of Hg, compared to the leaf area index (LAI) based scheme that is often used by previous models. We find the global distribution of litter Hg concentrations driven by vegetation uptake of atmospheric Hg(0), which are simulated to be higher in East Asia (87 ng/g) than in the Amazon region (63 ng/g). Meanwhile, as a significant source for litter Hg, the formation of structural litter (cellulose litter + lignin litter) results in a lagging effect between Hg(0) deposition and litter Hg concentration, implying the buffering effect of vegetation on the air-land exchange of Hg. This work highlights the importance of vegetation physiology and environmental factors in understanding the vegetation sequestration of atmospheric Hg globally, and calls for greater efforts to protect forests and afforestation.
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Affiliation(s)
- Tengfei Yuan
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Peng Zhang
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Zhengcheng Song
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Shaojian Huang
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Xun Wang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Yanxu Zhang
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu 210023, China; Frontiers Science Center for Critical Earth Material Cycling, Nanjing University, Nanjing 210023, China.
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25
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Langer M, von Deimling TS, Westermann S, Rolph R, Rutte R, Antonova S, Rachold V, Schultz M, Oehme A, Grosse G. Thawing permafrost poses environmental threat to thousands of sites with legacy industrial contamination. Nat Commun 2023; 14:1721. [PMID: 36977724 PMCID: PMC10050325 DOI: 10.1038/s41467-023-37276-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 03/09/2023] [Indexed: 03/30/2023] Open
Abstract
Industrial contaminants accumulated in Arctic permafrost regions have been largely neglected in existing climate impact analyses. Here we identify about 4500 industrial sites where potentially hazardous substances are actively handled or stored in the permafrost-dominated regions of the Arctic. Furthermore, we estimate that between 13,000 and 20,000 contaminated sites are related to these industrial sites. Ongoing climate warming will increase the risk of contamination and mobilization of toxic substances since about 1100 industrial sites and 3500 to 5200 contaminated sites located in regions of stable permafrost will start to thaw before the end of this century. This poses a serious environmental threat, which is exacerbated by climate change in the near future. To avoid future environmental hazards, reliable long-term planning strategies for industrial and contaminated sites are needed that take into account the impacts of cimate change.
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Affiliation(s)
- Moritz Langer
- Permafrost Research Section, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Potsdam, Germany.
- Department of Earth Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.
| | - Thomas Schneider von Deimling
- Permafrost Research Section, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
- Geography Department, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Sebastian Westermann
- Department of Geosciences, University of Oslo, Oslo, Norway
- Centre for Biogeochemistry in the Anthropocene, University of Oslo, Oslo, Norway
| | - Rebecca Rolph
- Permafrost Research Section, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
- Geography Department, Humboldt-Universität zu Berlin, Berlin, Germany
| | | | - Sofia Antonova
- Permafrost Research Section, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
| | - Volker Rachold
- German Arctic Office, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
| | | | - Alexander Oehme
- Permafrost Research Section, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
- Geography Department, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Guido Grosse
- Permafrost Research Section, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
- Institute of Geosciences, University of Potsdam, Potsdam, Germany
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26
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Zhou P, Liu W, Zhang X, Wang J. Evaluating Permafrost Degradation in the Tuotuo River Basin by MT-InSAR and LSTM Methods. SENSORS (BASEL, SWITZERLAND) 2023; 23:1215. [PMID: 36772259 PMCID: PMC9919772 DOI: 10.3390/s23031215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 01/09/2023] [Accepted: 01/13/2023] [Indexed: 06/18/2023]
Abstract
Permafrost degradation can significantly affect vegetation, infrastructure, and sustainable development on the Qinghai-Tibet Plateau (QTP). The permafrost on the QTP faces a risk of widespread degradation due to climate change and ecosystem disturbances; thus, monitoring its changes is critical. In this study, we conducted a permafrost surface deformation prediction over the Tuotuo River tributary watershed in the southwestern part of the QTP using the Long Short-Term Memory model (LSTM). The LSTM model was applied to the deformation information derived from a time series of Multi-Temporal Interferometry Synthetic Aperture Radar (MT-InSAR). First, we designed a quadtree segmentation-based Small BAseline Subset (SBAS) to monitor the seasonal permafrost deformation from March 2017 to April 2022. Then, the types of frozen soil were classified using the spatio-temporal deformation information and the temperature at the top of the permafrost. Finally, the time-series deformation trends of different types of permafrost were predicted using the LSTM model. The results showed that the deformation rates in the Tuotuo River Basin ranged between -80 to 60 mm/yr. Permafrost, seasonally frozen ground, and potentially degraded permafrost covered 7572.23, 900.87, and 921.70 km2, respectively. The LSTM model achieved high precision for frozen soil deformation prediction at the point scale, with a root mean square error of 4.457 mm and mean absolute error of 3.421 mm. The results demonstrated that deformation monitoring and prediction using MT-InSAR technology integrated with the LSTM model can be used to accurately identify types of permafrost over a large region and quantitatively evaluate its degradation trends.
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Affiliation(s)
- Ping Zhou
- School of Geosciences and Resources, China University of Geosciences (Beijing), Beijing 100083, China
| | - Weichao Liu
- School of Geosciences and Resources, China University of Geosciences (Beijing), Beijing 100083, China
| | - Xuefei Zhang
- Land Satellite Remote Sensing Application Center, Ministry of Natural Resources, Beijing 100048, China
| | - Jing Wang
- Zhejiang Laboratory, Research Institute of Intelligent Computing, Hangzhou 311121, China
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27
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Wang Y, Wu P, Zhang Y. Climate-driven changes of global marine mercury cycles in 2100. Proc Natl Acad Sci U S A 2023; 120:e2202488120. [PMID: 36595667 PMCID: PMC9926249 DOI: 10.1073/pnas.2202488120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 11/08/2022] [Indexed: 01/05/2023] Open
Abstract
Human exposure to monomethylmercury (CH3Hg), a potent neurotoxin, is principally through the consumption of seafood. The formation of CH3Hg and its bioaccumulation in marine food webs experience ongoing impacts of global climate warming and ocean biogeochemistry alterations. Employing a series of sensitivity experiments, here we explicitly consider the effects of climate change on marine mercury (Hg) cycling within a global ocean model in the hypothesized twenty-first century under the business-as-usual scenario. Even though the overall prediction is subjected to significant uncertainty, we identify several important climate change impact pathways. Elevated seawater temperature exacerbates elemental Hg (Hg0) evasion, while decreased surface wind speed reduces air-sea exchange rates. The reduced export of particulate organic carbon shrinks the pool of potentially bioavailable divalent Hg (HgII) that can be methylated in the subsurface ocean, where shallower remineralization depth associated with lower productivity causes impairment of methylation activity. We also simulate an increase in CH3Hg photodemethylation potential caused by increased incident shortwave radiation and less attenuation by decreased sea ice and chlorophyll. The model suggests that these impacts can also be propagated to the CH3Hg concentration in the base of the marine food web. Our results offer insight into synergisms/antagonisms in the marine Hg cycling among different climate change stressors.
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Affiliation(s)
- Yujuan Wang
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu210023, China
| | - Peipei Wu
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu210023, China
| | - Yanxu Zhang
- School of Atmospheric Sciences, Nanjing University, Nanjing, Jiangsu210023, China
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Breitmeyer SE, Walsh HL, Blazer VS, Bunnell JF, Burritt PM, Dragon J, Hladik ML, Bradley PM, Romanok KM, Smalling KL. Potential health effects of contaminant mixtures from point and nonpoint sources on fish and frogs in the New Jersey Pinelands. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 851:158205. [PMID: 36028019 DOI: 10.1016/j.scitotenv.2022.158205] [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: 05/16/2022] [Revised: 08/17/2022] [Accepted: 08/18/2022] [Indexed: 06/15/2023]
Abstract
Aquatic ecosystems convey complex contaminant mixtures from anthropogenic pollution on a global scale. Point (e.g., municipal wastewater) and nonpoint sources (e.g., stormwater runoff) are both drivers of contaminant mixtures in aquatic habitats. The objectives of this study were to identify the contaminant mixtures present in surface waters impacted by both point and nonpoint sources, to determine if aquatic biota (amphibian and fish) health effects (testicular oocytes and parasites) occurred at these sites, and to understand if differences in biological and chemical measures existed between point (on-stream) and nonpoint sources (off-stream). To accomplish this, water chemistry, fishes, and frogs were collected from 21 sites in the New Jersey Pinelands, United States. Off-stream sites consisted of 3 reference and 10 degraded wetlands. On-stream sites consisted of two reference lakes and six degraded streams/lakes (four sites above and two sites below wastewater outfalls). Surface water was collected four times at each site and analyzed for 133 organic and inorganic contaminants. One native and five non-native fish species were collected from streams/lakes and native green frogs from wetlands (ponds and stormwater basins). Limited differences in contaminant concentrations were observed in reference and degraded wetlands but for streams/lakes, results indicated that landscape alteration, (upland agricultural and developed land) was the primary driver of contaminant concentrations rather than municipal wastewater. Incidence of estrogenic endocrine disruption (intersex) was species dependent with the highest prevalence observed in largemouth bass and black crappie and the lowest prevalence observed in green frogs and tessellated darters. Parasite prevalence was site and species dependent. Prevalence of eye parasites increased with increasing concentrations of industrial, mycotoxin, and cumulative inorganic contaminants. These findings are critical to support the conservation, protection, and management of a wide range of aquatic species in the Pinelands and elsewhere as habitat loss, alteration, and fragmentation increase with increasing development.
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Affiliation(s)
- Sara E Breitmeyer
- U.S. Geological Survey, New Jersey Water Science Center, 3450 Princeton Pike, Suite 110, Lawrenceville, NJ 08648, USA.
| | - Heather L Walsh
- U.S. Geological Survey, Eastern Ecological Science Center, 11649 Leetown Road, Kearneysville, WV 25430, USA
| | - Vicki S Blazer
- U.S. Geological Survey, Eastern Ecological Science Center, 11649 Leetown Road, Kearneysville, WV 25430, USA
| | - John F Bunnell
- New Jersey Pinelands Commission, PO Box 359, 15 Springfield Road, New Lisbon, NJ 08064, USA
| | - Patrick M Burritt
- New Jersey Pinelands Commission, PO Box 359, 15 Springfield Road, New Lisbon, NJ 08064, USA
| | - Jeff Dragon
- New Jersey Pinelands Commission, PO Box 359, 15 Springfield Road, New Lisbon, NJ 08064, USA
| | - Michelle L Hladik
- U.S. Geological Survey, California Water Science Center, 6000 J St, Placer Hall, Sacramento, CA 95819, USA
| | - Paul M Bradley
- U.S. Geological Survey, South Atlantic Water Science Center, 720 Gracern Rd, Suite 129, Columbia, SC 29210, USA
| | - Kristin M Romanok
- U.S. Geological Survey, New Jersey Water Science Center, 3450 Princeton Pike, Suite 110, Lawrenceville, NJ 08648, USA
| | - Kelly L Smalling
- U.S. Geological Survey, New Jersey Water Science Center, 3450 Princeton Pike, Suite 110, Lawrenceville, NJ 08648, USA
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29
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Jonsson S, Mastromonaco MN, Wang F, Bravo AG, Cairns WRL, Chételat J, Douglas TA, Lescord G, Ukonmaanaho L, Heimbürger-Boavida LE. Arctic methylmercury cycling. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 850:157445. [PMID: 35882324 DOI: 10.1016/j.scitotenv.2022.157445] [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: 01/31/2022] [Revised: 07/12/2022] [Accepted: 07/13/2022] [Indexed: 06/15/2023]
Abstract
Anthropogenic mercury (Hg) undergoes long-range transport to the Arctic where some of it is transformed into methylmercury (MeHg), potentially leading to high exposure in some Arctic inhabitants and wildlife. The environmental exposure of Hg is determined not just by the amount of Hg entering the Arctic, but also by biogeochemical and ecological processes occurring in the Arctic. These processes affect MeHg uptake in biota by regulating the bioavailability, methylation and demethylation, bioaccumulation and biomagnification of MeHg in Arctic ecosystems. Here, we present a new budget for pools and fluxes of MeHg in the Arctic and review the scientific advances made in the last decade on processes leading to environmental exposure to Hg. Methylation and demethylation are key processes controlling the pool of MeHg available for bioaccumulation. Methylation of Hg occurs in diverse Arctic environments including permafrost, sediments and the ocean water column, and is primarily a process carried out by microorganisms. While microorganisms carrying the hgcAB gene pair (responsible for Hg methylation) have been identified in Arctic soils and thawing permafrost, the formation pathway of MeHg in oxic marine waters remains less clear. Hotspots for methylation of Hg in terrestrial environments include thermokarst wetlands, ponds and lakes. The shallow sub-surface enrichment of MeHg in the Arctic Ocean, in comparison to other marine systems, is a possible explanation for high MeHg concentrations in some Arctic biota. Bioconcentration of aqueous MeHg in bacteria and algae is a critical step in the transfer of Hg to top predators, which may be dampened or enhanced by the presence of organic matter. Variable trophic position has an important influence on MeHg concentrations among populations of top predator species such as ringed seal and polar bears distributed across the circumpolar Arctic. These scientific advances highlight key processes that affect the fate of anthropogenic Hg deposited to Arctic environments.
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Affiliation(s)
- Sofi Jonsson
- Department of Environmental Science, Stockholm University, SE-106 91 Stockholm, Sweden.
| | | | - Feiyue Wang
- Centre for Earth Observation Science, and Department of Environment and Geography, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Andrea G Bravo
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar (ICM-CSIC), Barcelona, Spain
| | - Warren R L Cairns
- CNR Institute of Polar Sciences and Ca' Foscari University, Venice, Italy
| | - John Chételat
- Environment and Climate Change Canada, National Wildlife Research Centre, Ottawa, ON, Canada
| | - Thomas A Douglas
- U.S. Army Cold Regions Research and Engineering Laboratory, Fort Wainwright, AK, USA
| | - Gretchen Lescord
- Wildlife Conservation Society Canada and Laurentian University, Vale Living with Lakes Center, Sudbury, Ontario, Canada
| | - Liisa Ukonmaanaho
- Natural Resources Institute Finland (Luke), P.O. Box 2, FI-00791 Helsinki, Finland
| | - Lars-Eric Heimbürger-Boavida
- CNRS/INSU,Aix Marseille Université,Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO), Marseille, France
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Schartup AT, Soerensen AL, Angot H, Bowman K, Selin NE. What are the likely changes in mercury concentration in the Arctic atmosphere and ocean under future emissions scenarios? THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 836:155477. [PMID: 35472347 DOI: 10.1016/j.scitotenv.2022.155477] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 04/12/2022] [Accepted: 04/19/2022] [Indexed: 06/14/2023]
Abstract
Arctic mercury (Hg) concentrations respond to changes in anthropogenic Hg emissions and environmental change. This manuscript, prepared for the 2021 Arctic Monitoring and Assessment Programme Mercury Assessment, explores the response of Arctic Ocean Hg concentrations to changing primary Hg emissions and to changing sea-ice cover, river inputs, and net primary production. To do this, we conduct a model analysis using a 2015 Hg inventory and future anthropogenic Hg emission scenarios. We model future atmospheric Hg deposition to the surface ocean as a flux to the surface water or sea ice using three scenarios: No Action, New Policy (NP), and Maximum Feasible Reduction (MFR). We then force a five-compartment box model of Hg cycling in the Arctic Ocean with these scenarios and literature-derived climate variables to simulate environmental change. No Action results in a 51% higher Hg deposition rate by 2050 while increasing Hg concentrations in the surface water by 22% and <9% at depth. Both "action" scenarios (NP and MFR), implemented in 2020 or 2035, result in lower Hg deposition ranging from 7% (NP delayed to 2035) to 30% (MFR implemented in 2020) by 2050. Under this last scenario, ocean Hg concentrations decline by 14% in the surface and 4% at depth. We find that the sea-ice cover decline exerts the strongest Hg reducing forcing on the Arctic Ocean while increasing river discharge increases Hg concentrations. When modified together the climate scenarios result in a ≤5% Hg decline by 2050 in the Arctic Ocean. Thus, we show that the magnitude of emissions-induced future changes in the Arctic Ocean is likely to be substantial compared to climate-induced effects. Furthermore, this study underscores the need for prompt and ambitious action for changing Hg concentrations in the Arctic, since delaying less ambitious reduction measures-like NP-until 2035 may become offset by Hg accumulated from pre-2035 emissions.
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Affiliation(s)
- Amina T Schartup
- Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA 92093, USA.
| | - Anne L Soerensen
- Department of Environmental Research and Monitoring, Swedish Museum of Natural History, Stockholm, Sweden
| | - Hélène Angot
- Extreme Environments Research Laboratory, École Polytechnique Fédérale de Lausanne (EPFL) Valais Wallis, Sion, Switzerland
| | - Katlin Bowman
- University of California Santa Cruz, Ocean Sciences Department, 1156 High Street, Santa Cruz, CA 95064, USA
| | - Noelle E Selin
- Institute for Data, Systems, and Society, and Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue [E17-381], Cambridge. MA 02139, USA
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31
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Mercury isotope evidence for Arctic summertime re-emission of mercury from the cryosphere. Nat Commun 2022; 13:4956. [PMID: 36002442 PMCID: PMC9402541 DOI: 10.1038/s41467-022-32440-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 07/29/2022] [Indexed: 11/28/2022] Open
Abstract
During Arctic springtime, halogen radicals oxidize atmospheric elemental mercury (Hg0), which deposits to the cryosphere. This is followed by a summertime atmospheric Hg0 peak that is thought to result mostly from terrestrial Hg inputs to the Arctic Ocean, followed by photoreduction and emission to air. The large terrestrial Hg contribution to the Arctic Ocean and global atmosphere has raised concern over the potential release of permafrost Hg, via rivers and coastal erosion, with Arctic warming. Here we investigate Hg isotope variability of Arctic atmospheric, marine, and terrestrial Hg. We observe highly characteristic Hg isotope signatures during the summertime peak that reflect re-emission of Hg deposited to the cryosphere during spring. Air mass back trajectories support a cryospheric Hg emission source but no major terrestrial source. This implies that terrestrial Hg inputs to the Arctic Ocean remain in the marine ecosystem, without substantial loss to the global atmosphere, but with possible effects on food webs. Arctic warming thaws permafrost, leading to enhanced soil mercury transport to the Arctic Ocean. Mercury isotope signatures in arctic rivers, ocean and atmosphere suggest that permafrost mercury is buried in marine sediment and not emitted to the global atmosphere
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32
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Walther EJ, Arthur DE, Cyr A, Fraley KM, Cubbage T, Hinkle E, McMahon J, Westley PAH. Ecotoxicology of mercury in burbot (Lota lota) from interior Alaska and insights towards human health. CHEMOSPHERE 2022; 298:134279. [PMID: 35283142 PMCID: PMC9081214 DOI: 10.1016/j.chemosphere.2022.134279] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 03/03/2022] [Accepted: 03/07/2022] [Indexed: 05/26/2023]
Abstract
Fish consumption has many health benefits, but exposure to contaminants, such as mercury (Hg), in fish tissue can be detrimental to human health. The Tanana River drainage, Alaska, USA supports the largest recreational harvest of burbot (Lota lota) in the state, yet information to evaluate the potential risks of consumption by humans is lacking. To narrow this knowledge gap, we sought to (i) quantify the concentrations of total Hg ([THg]) in burbot muscle and liver tissue and the ratio between the two tissues, (ii) assess the effect of age, length, and sex on [THg] in muscle and liver tissue, (iii) evaluate if [THg] in muscle tissue varied based on trophic information, and (iv) compare observed [THg] to consumption guidelines and statewide baseline data. The mean [THg] was 268.2 ng/g ww for muscle tissue and 62.3 ng/g ww for liver tissue. Both muscle [THg] and liver [THg] values were positively associated with fish length. Trophic information (δ15N and δ13C) was not significantly related to measured [THg] in burbot muscle, which is inconsistent with typical patterns of biomagnification observed in other fishes. All burbot sampled were within the established categories for consumption recommendations determined by the State of Alaska for women of childbearing age and children. Our results provide the necessary first step towards informed risk assessment of burbot consumption in the Tanana drainage and offer parallels to fisheries and consumers throughout the subarctic and Arctic region.
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Affiliation(s)
- Eric J Walther
- Department of Fisheries, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA.
| | - Donald E Arthur
- Department of Fisheries, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA.
| | - Andrew Cyr
- Department of Fisheries, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA; Department of Veterinary Medicine, College of Natural Sciences and Mathematics, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA
| | - Kevin M Fraley
- Arctic Beringia Program, Wildlife Conservation Society, Fairbanks, AK, 99709, USA
| | - Taylor Cubbage
- Department of Fisheries, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA
| | - Elizabeth Hinkle
- Department of Fisheries, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA
| | - Julia McMahon
- Department of Fisheries, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA
| | - Peter A H Westley
- Department of Fisheries, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA.
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Accuracy, Efficiency, and Transferability of a Deep Learning Model for Mapping Retrogressive Thaw Slumps across the Canadian Arctic. REMOTE SENSING 2022. [DOI: 10.3390/rs14122747] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Deep learning has been used for mapping retrogressive thaw slumps and other periglacial landforms but its application is still limited to local study areas. To understand the accuracy, efficiency, and transferability of a deep learning model (i.e., DeepLabv3+) when applied to large areas or multiple regions, we conducted several experiments using training data from three different regions across the Canadian Arctic. To overcome the main challenge of transferability, we used a generative adversarial network (GAN) called CycleGAN to produce new training data in an attempt to improve transferability. The results show that (1) data augmentation can improve the accuracy of the deep learning model but does not guarantee transferability, (2) it is necessary to choose a good combination of hyper-parameters (e.g., backbones and learning rate) to achieve an optimal trade-off between accuracy and efficiency, and (3) a GAN can significantly improve the transferability if the variation between source and target is dominated by color or general texture. Our results suggest that future mapping of retrogressive thaw slumps should prioritize the collection of training data from regions where a GAN cannot improve the transferability.
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34
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Kim J, Kwon SY, Kim K, Han S. Import, export, and speciation of mercury in Kongsfjorden, Svalbard: Influences of glacier melt and river discharge. MARINE POLLUTION BULLETIN 2022; 179:113693. [PMID: 35525059 DOI: 10.1016/j.marpolbul.2022.113693] [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: 02/05/2022] [Revised: 04/07/2022] [Accepted: 04/22/2022] [Indexed: 06/14/2023]
Abstract
The major sources and sinks of total mercury (THg) and methylmercury (MeHg) in Kongsfjorden were estimated based on spreadsheet-based ecological risk assessment for the fate of mercury (SERAFM). SERAFM was parameterized and calibrated to fit Kongsfjorden using the physical properties of the fjord, runoff coefficients of Hg, transformation rate constants of Hg, partition coefficients of Hg, Hg loadings from freshwater, and solid balance parameters. The modeled Hg concentrations in the seawater matched with the measured concentrations, with a mean bias of 12% and a calibration error of 0.035. The mass budget showed that the major THg sources were tidal inflow and glacial runoff, while the major MeHg sources were tidal inflow and in situ methylation in shallow halocline water, which agreed with the distributions of THg and MeHg in seawater. The coupling of observation and fate modeling in Kongsfjorden provides a basic understanding of Hg cycles in the Arctic fjords.
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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
| | - Sae Yun Kwon
- Division of Environmental Science and Engineering, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
| | - Kitae Kim
- Korea Polar Research Institute (KOPRI), Incheon 21990, Republic of Korea; Department of Polar Science, University of Science and Technology, 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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Multidecadal declines in particulate mercury and sediment export from Russian rivers in the pan-Arctic basin. Proc Natl Acad Sci U S A 2022; 119:e2119857119. [PMID: 35344436 PMCID: PMC9168841 DOI: 10.1073/pnas.2119857119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Russian rivers are the predominant source of riverine mercury to the Arctic Ocean, where methylmercury biomagnifies to high levels in food webs. Pollution controls are thought to have decreased late–20th-century mercury loading to Arctic watersheds, but there are no published long-term observations on mercury in Russian rivers. Here, we present a unique hydrochemistry dataset to determine trends in Russian river particulate mercury concentrations and fluxes in recent decades. Using hydrologic and mercury deposition modeling together with multivariate time series analysis, we determine that 70 to 90% declines in particulate mercury fluxes were driven by pollution reductions and sedimentation in reservoirs. Results suggest that Russian rivers likely dominated over all other sources of mercury to the Arctic Ocean until recently. High levels of methylmercury accumulation in marine biota are a concern throughout the Arctic, where coastal ocean ecosystems received large riverine inputs of mercury (Hg) (40 Mg⋅y−1) and sediment (20 Tg⋅y−1) during the last decade, primarily from major Russian rivers. Hg concentrations in fish harvested from these rivers have declined since the late 20th century, but no temporal data on riverine Hg, which is often strongly associated with suspended sediments, were previously available. Here, we investigate temporal trends in Russian river particulate Hg (PHg) and total suspended solids (TSS) to better understand recent changes in the Arctic Hg cycle and its potential future trajectories. We used 1,300 measurements of Hg in TSS together with discharge observations made by Russian hydrochemistry and hydrology monitoring programs to examine changes in PHg and TSS concentrations and fluxes in eight major Russian rivers between ca. 1975 and 2010. Due to decreases in both PHg concentrations (micrograms per gram) and TSS loads, annual PHg export declined from 47 to 7 Mg⋅y−1 overall and up to 92% for individual rivers. Modeling of atmospheric Hg deposition together with published inventories on reservoir establishment and industrial Hg release point to decreased pollution and sedimentation within reservoirs as predominant drivers of declining PHg export. We estimate that Russian rivers were the primary source of Hg to the Arctic Ocean in the mid to late 20th century.
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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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Tong YJ, Yu LD, Li N, Fu Q, Xu K, Wei J, Ye YX, Xu J, Zhu F, Pawliszyn J, Ouyang G. Ratiometric fluorescent probe for the on-site monitoring of coexisted Hg 2+ and F - in sequence. Anal Chim Acta 2021; 1183:338967. [PMID: 34627509 DOI: 10.1016/j.aca.2021.338967] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 08/05/2021] [Accepted: 08/17/2021] [Indexed: 12/23/2022]
Abstract
The monitoring of mercury and fluoride ions (Hg2+ and F-) has aroused wide concerns owing to the high toxicity of Hg2+ and the duplicitous nature of F- to human health. As far as we known, more than 100 million people in poverty-stricken areas are still at high risk of being over-exposed to Hg2+ and F- via drinking water. Simple and cost-effective luminescent methods are highly promising for on-site water monitoring in rural areas. However, the development of multipurpose luminescent probes that are accurate and sensitive remains challenging. Herein, a new strategy for rationally designing a multipurpose ratiometric probe is present. The obtained probe is consisted of two emission units with energy transfer between them, which exhibit high coordination affinities to the two coexisted toxic targets (Hg2+ and F-), respectively. Thus, two distinct routes for efficiently modulating the energy transfer in the probe are present to trigger the responses to the two targets in sequence. By detecting the shift of the emission color with a smartphone, an on-site water monitoring method is successfully established with the detection limits as low as 2.7 nM for Hg2+ and 1.9 μM for F-. The present study can expend the toolbox for water monitoring in rural regions.
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Affiliation(s)
- Yuan-Jun Tong
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, 510275, China
| | - Lu-Dan Yu
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, 510275, China
| | - Nan Li
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, 510275, China
| | - Qi Fu
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, 510275, China
| | - Ke Xu
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, 510275, China
| | - Jiajun Wei
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, 510275, China
| | - Yu-Xin Ye
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, 510275, China
| | - Jianqiao Xu
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, 510275, China.
| | - Fang Zhu
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, 510275, China
| | - Janusz Pawliszyn
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L3G1, Canada
| | - Gangfeng Ouyang
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, 510275, China; Chemistry College, Center of Advanced Analysis and Gene Sequencing, Zhengzhou University, Kexue Avenue 100, Zhengzhou, 450001, China; Guangdong Provincial Key Laboratory of Emergency Test for Dangerous Chemicals, Guangdong Institute of Analysis (China National Analytical Center Guangzhou), Guangdong Academy of Sciences, 100 Xianlie Middle Road, Guangzhou, 510070, China
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Roth S, Poulin BA, Baumann Z, Liu X, Zhang L, Krabbenhoft DP, Hines ME, Schaefer JK, Barkay T. Nutrient Inputs Stimulate Mercury Methylation by Syntrophs in a Subarctic Peatland. Front Microbiol 2021; 12:741523. [PMID: 34675906 PMCID: PMC8524442 DOI: 10.3389/fmicb.2021.741523] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 09/13/2021] [Indexed: 11/13/2022] Open
Abstract
Climate change dramatically impacts Arctic and subarctic regions, inducing shifts in wetland nutrient regimes as a consequence of thawing permafrost. Altered hydrological regimes may drive changes in the dynamics of microbial mercury (Hg) methylation and bioavailability. Important knowledge gaps remain on the contribution of specific microbial groups to methylmercury (MeHg) production in wetlands of various trophic status. Here, we measured aqueous chemistry, potential methylation rates (kmeth), volatile fatty acid (VFA) dynamics in peat-soil incubations, and genetic potential for Hg methylation across a groundwater-driven nutrient gradient in an interior Alaskan fen. We tested the hypotheses that (1) nutrient inputs will result in increased methylation potentials, and (2) syntrophic interactions contribute to methylation in subarctic wetlands. We observed that concentrations of nutrients, total Hg, and MeHg, abundance of hgcA genes, and rates of methylation in peat incubations (kmeth) were highest near the groundwater input and declined downgradient. hgcA sequences near the input were closely related to those from sulfate-reducing bacteria (SRB), methanogens, and syntrophs. Hg methylation in peat incubations collected near the input source (FPF2) were impacted by the addition of sulfate and some metabolic inhibitors while those down-gradient (FPF5) were not. Sulfate amendment to FPF2 incubations had higher kmeth relative to unamended controls despite no effect on kmeth from addition of the sulfate reduction inhibitor molybdate. The addition of the methanogenic inhibitor BES (25 mM) led to the accumulation of VFAs, but unlike molybdate, it did not affect Hg methylation rates. Rather, the concurrent additions of BES and molybdate significantly decreased kmeth, suggesting a role for interactions between SRB and methanogens in Hg methylation. The reduction in kmeth with combined addition of BES and molybdate, and accumulation of VFA in peat incubations containing BES, and a high abundance of syntroph-related hgcA sequences in peat metagenomes provide evidence for MeHg production by microorganisms growing in syntrophy. Collectively the results suggest that wetland nutrient regimes influence the activity of Hg methylating microorganisms and, consequently, Hg methylation rates. Our results provide key information about microbial Hg methylation and methylating communities under nutrient conditions that are expected to become more common as permafrost soils thaw.
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Affiliation(s)
- Spencer Roth
- Department of Environmental Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States.,Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States
| | - Brett A Poulin
- Department of Environmental Toxicology, University of California, Davis, Davis, CA, United States
| | - Zofia Baumann
- Department of Marine Sciences, University of Connecticut, Groton, CT, United States
| | - Xiao Liu
- Department of Biological Sciences, University of Massachusetts, Lowell, MA, United States.,Department of Physical and Environmental Sciences, Texas A&M University - Corpus Christi, Corpus Christi, TX, United States
| | - Lin Zhang
- Department of Physical and Environmental Sciences, Texas A&M University - Corpus Christi, Corpus Christi, TX, United States
| | - David P Krabbenhoft
- United States Geological Survey, Upper Midwest Water Science Center, Mercury Research Laboratory, Middleton, WI, United States
| | - Mark E Hines
- Department of Biological Sciences, University of Massachusetts, Lowell, MA, United States
| | - Jeffra K Schaefer
- Department of Environmental Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States
| | - Tamar Barkay
- Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States
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