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Gačnik J, Živković I, Kotnik J, Božič D, Tassone A, Naccarato A, Pirrone N, Sprovieri F, Steffen A, Horvat M. Comparison of active measurements, lichen biomonitoring, and passive sampling for atmospheric mercury monitoring. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:35800-35810. [PMID: 38740686 PMCID: PMC11136809 DOI: 10.1007/s11356-024-33582-6] [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: 10/04/2023] [Accepted: 05/01/2024] [Indexed: 05/16/2024]
Abstract
The number of atmospheric mercury (Hg) monitoring stations is growing globally. However, there are still many regions and locations where Hg monitoring is limited or non-existent. Expansion of the atmospheric Hg monitoring network could be facilitated by the use of cost-effective monitoring methods. As such, biomonitoring and passive monitoring offer a unique alternative to well-established monitoring by active measurements, since they do not require a power supply and require minimal workload to operate. The use of biomonitoring (lichens and mosses) and passive air samplers (PASs) (various designs with synthetic materials) has been reported in the literature, and comparisons with active measurement methods have also been made. However, these studies compared either biomonitoring or PASs (not both) to only one type of active measurement. In our work, we used transplanted (7 sampling sites) and in situ lichens (8 sampling sites) for biomonitoring, two PASs from different producers (3 sampling sites), and two different active measurement types (continuous and discontinuous active measurements, 1 and 8 sampling sites, respectively) to evaluate their effectiveness as monitoring methods. In the 9-month sampling campaign, 3 sampling locations with different characteristics (unpolluted, vicinity of a cement plant, and vicinity of a former Hg mine) were used. The results obtained with lichens and PASs clearly distinguished between sampling locations with different Hg concentrations; using both PASs and lichens together increased the confidence of our observations. The present work shows that biomonitoring and passive sampling can be effectively used to identify areas with elevated atmospheric Hg concentrations. The same can be said for discontinuous active measurements; however, the discrepancy between atmospheric Hg concentrations derived from PASs and discontinuous active measurements should be further investigated in the future.
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Affiliation(s)
- Jan Gačnik
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Igor Živković
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Jože Kotnik
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Dominik Božič
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Antonella Tassone
- Institute of Atmospheric Pollution Research, National Research Council, Rende, Italy
| | - Attilio Naccarato
- Institute of Atmospheric Pollution Research, National Research Council, Rende, Italy
- Department of Chemistry and Chemical Technologies, University of Calabria, Rende, Italy
| | - Nicola Pirrone
- Institute of Atmospheric Pollution Research, National Research Council, Rende, Italy
| | - Francesca Sprovieri
- Institute of Atmospheric Pollution Research, National Research Council, Rende, Italy
| | - Alexandra Steffen
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Canada
| | - Milena Horvat
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana, Slovenia.
- Jožef Stefan International Postgraduate School, Ljubljana, Slovenia.
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Zhu W, Li Z, Li P, Sommar J, Fu X, Feng X, Yu B, Zhang W, Reis AT, Pereira E. Legacy Mercury Re-emission and Subsurface Migration at Contaminated Sites Constrained by Hg Isotopes and Chemical Speciation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:5336-5346. [PMID: 38472090 DOI: 10.1021/acs.est.3c07276] [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: 03/14/2024]
Abstract
The re-emission and subsurface migration of legacy mercury (Hg) are not well understood due to limited knowledge of the driving processes. To investigate these processes at a decommissioned chlor-alkali plant, we used mercury stable isotopes and chemical speciation analysis. The isotopic composition of volatilized Hg(0) was lighter compared to the bulk total Hg (THg) pool in salt-sludge and adjacent surface soil with mean ε202HgHg(0)-THg values of -3.29 and -2.35‰, respectively. Hg(0) exhibited dichotomous directions (E199HgHg(0)-THg = 0.17 and -0.16‰) of mass-independent fractionation (MIF) depending on the substrate from which it was emitted. We suggest that the positive MIF enrichment during Hg(0) re-emission from salt-sludge was overall controlled by the photoreduction of Hg(II) primarily ligated by Cl- and/or the evaporation of liquid Hg(0). In contrast, O-bonded Hg(II) species were more important in the adjacent surface soils. The migration of Hg from salt-sludge to subsurface soil associated with selective Hg(II) partitioning and speciation transformation resulted in deep soils depleted in heavy isotopes (δ202Hg = -2.5‰) and slightly enriched in odd isotopes (Δ199Hg = 0.1‰). When tracing sources using Hg isotopes, it is important to exercise caution, particularly when dealing with mobilized Hg, as this fraction represents only a small portion of the sources.
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Affiliation(s)
- Wei Zhu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå SE-90183, Sweden
| | - Zhonggen Li
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
- School of Resources and Environment, Zunyi Normal College, Zunyi 563006, China
| | - Ping Li
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jonas Sommar
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Xuewu Fu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ben Yu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Wei Zhang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Ana T Reis
- EPIUnit─Instituto de Saúde Pública, Universidade do Porto, Porto 4050-600, Portugal
- Laboratório para a Investigação Integrativa e Translacional em Saúde Populacional (ITR), Porto 4050-600, Portugal
| | - Eduarda Pereira
- LAQV-REQUIMTE─Associated Laboratory for Green Chemistry, University of Aveiro, Aveiro 3810-193, Portugal
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Zhu S, Wang Y, Hursthouse A, Luo W, Maher WA. Modelling selenium behavior in aquatic systems: a review of status, challenges, and opportunities. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:12832-12840. [PMID: 38277100 DOI: 10.1007/s11356-024-32091-w] [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: 06/05/2023] [Accepted: 01/16/2024] [Indexed: 01/27/2024]
Abstract
Selenium (Se) is an essential element for aquatic organisms as well as humans. It can be toxic to organisms depending on its concentration and chemical speciation; thus, considerable efforts have been made to unravel the biogeochemical cycling of Se in aquatic systems. Mathematical models provide an important tool to better understand the fate of Se in different environment compartments. However, a comprehensive review of modeling Se in aquatic systems with current challenges and opportunities is missing. To fill this gap, we firstly summarize the processes governing Se cycling in aquatic systems, including particle adsorption and desorption, diffusion, biological uptake, redox reactions, and volatilization. Then, we critically review the available models, identifying the compartments modelled, environmental factors considered, and the Se species and geochemical processes used in each model, providing an assessment of their advantages and limitations. Data availability for modeling studies is investigated, highlighting how to better quantify the redox reactions, estimate of Se loadings, and mass balance. For the modeling of Se cycling in aquatic systems, the ability of the models to link sources to biota concentrations under a range of hydrodynamic conditions and with mechanistic representations of transport, transformation, and uptake processes is required. The majority of the current models can conduct this task; however, to better present the uptake processes of Se in the food web, two-way coupling of the Se cycling model with a food web model is recommended.
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Affiliation(s)
- Senlin Zhu
- College of Hydraulic Science and Engineering, Yangzhou University, Yangzhou, China.
| | - Yanping Wang
- School of Geographical Science, Nantong University, Nantong, China
| | - Andrew Hursthouse
- School of Computing, Engineering & Physical Sciences, University of the West of Scotland, Paisley, Scotland, PA1 2BE, UK
| | - Wenguang Luo
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, 430072, Hubei, China
| | - William A Maher
- Research School of Earth Sciences, Australian National University, Canberra, ACT, 2601, Australia
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Kim YG, Kwon SY, Washburn SJ, Hong Y, Han SH, Lee M, Park JH. Environmental forensics approach to source investigation in a mercury contaminated river: Insights from mercury stable isotopes. JOURNAL OF HAZARDOUS MATERIALS 2024; 461:132559. [PMID: 37729710 DOI: 10.1016/j.jhazmat.2023.132559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 08/10/2023] [Accepted: 09/12/2023] [Indexed: 09/22/2023]
Abstract
Environmental forensics approach was applied to assess the efficacy of mercury (Hg) stable isotopes for source screening and decision-making in the Hyeongsan River, South Korea. Four Hg contamination scenarios were identified- atmospheric Hg emissions from a steel manufacturing industry, upstream riverine Hg transport, and industrial Hg releases and historical landfill collapse from Gumu Creek. The absence of significant Hg isotope difference between the Hyeongsan River sediments (δ202Hg; -0.46 ± 0.17‰, Δ199Hg; -0.04 ± 0.06‰) and the Gumu Creek sediment (δ202Hg; -0.39 ± 0.26‰, Δ199Hg; -0.04 ± 0.03‰) confirm that Hg source is originated from Gumu Creek. The heterogeneous Hg distribution throughout Gumu Creek and statistically similar Hg isotope ratios between Gumu Creek and solid waste cores from the landfill suggests that the landfill collapse is the dominant source to the Hyeongsan-Gumu system. Present Hg releases is also possible given the elevated and matching Δ199Hg between some riverine sediments and wastewater sampled from the landfill. The ternary mixing model estimates that the landfill collapse and wastewater releases contribute 61 ± 25 % and 22 ± 11 %, and the regional background, reflecting terrestrial runoff using deep sediment cores, explain 17 ± 24 % of Hg to the riverine sediment. We suggest that Hg isotopes can be used for routine source screening in areas where Hg sources are unknown.
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Affiliation(s)
- Young Gwang Kim
- Division of Environmental Science and Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang 37673, South Korea
| | - Sae Yun Kwon
- Division of Environmental Science and Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang 37673, South Korea; Institute for Convergence Research and Education in Advanced Technology, Yonsei University, 85 Songdogwahak-Ro, Yeonsu-Gu, Incheon 21983, South Korea.
| | - Spencer J Washburn
- Geosyntec Consultants, Inc., 100 Washington Ave. S, Suite 1590, Minneapolis, MN 55401, USA
| | - Yongseok Hong
- Department of Environmental Engineering, Korea University Sejong Campus, 2511 Sejong-Ro, Sejong City 30019, South Korea
| | - Seung Hee Han
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-Ro, Buk-Gu, Gwangju 61005, South Korea
| | - Mikyung Lee
- Water Environmental Engineering Research Division, National Institute of Environmental Research, 42 Hwangyeong-Ro, Seo-Gu, Incheon 22689, South Korea
| | - Ji Hyoung Park
- Water Environmental Engineering Research Division, National Institute of Environmental Research, 42 Hwangyeong-Ro, Seo-Gu, Incheon 22689, South Korea
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Hu J, Zheng L, Liu S, Chen Y, Li C, Ni J, Chen Y, An S. Quantifying the impacts of coal mining activities on topsoil using Hg stable isotope: A case study of Guqiao mining area, Huainan City. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 335:122378. [PMID: 37586683 DOI: 10.1016/j.envpol.2023.122378] [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: 05/09/2023] [Revised: 07/30/2023] [Accepted: 08/12/2023] [Indexed: 08/18/2023]
Abstract
The Hg released from coal mining activities can endanger soil ecosystems and pose a risk to human health. Understanding the accumulation characteristics of mercury (Hg) in coal mining soil is important for effectively controlling Hg emissions and developing measures for the prevention and control of Hg contamination. To identify the potential sources of Hg in soils, the Hg concentration and isotopic composition characteristics of raw coal and different topsoil types from the areas surrounding a coal mine were determined in this study. The results showed that Hg in coal mainly exists mainly in the form of inorganic Hg, and Hg has experienced Hg2+ photoreduction prior to incorporating into coal. In addition, the composition of Hg isotopes differed significantly among different topsoil types, and the δ202Hg value of the farmland soil exhibited large negative excursions compared to the coal mining soil. The ternary mixed model further revealed the presence of substantial differences in potential Hg sources among the two regions, with the coal mining soil being greatly disturbed by anthropogenic activity, and the relative contributions of Hg from raw coal, coal gangue, and background soil to coal mining soil being 33.42%, 34.4%, and 32.19%, respectively. However, Hg from raw coal, coal gangue and background soil contributed 17.04%, 21.46%, and 61.51% of the Hg in the farmland soil, indicating that the accumulation of Hg in farmland soil was derived primarily from the background soil. Our study demonstrated that secondary pollution in soil caused by immense accumulation of solid waste (gangue) by mining activities offers a significant challenge to ecological security. These findings provide new insights into controlling soil Hg in mining areas and further highlight the urgency of strict protective measures for contaminated sites.
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Affiliation(s)
- Jie Hu
- School of Resources and Environmental Engineering, Anhui University, Anhui Province Engineering Laboratory for Mine Ecological Remediation, Hefei, 230601, Anhui, China
| | - Liugen Zheng
- School of Resources and Environmental Engineering, Anhui University, Anhui Province Engineering Laboratory for Mine Ecological Remediation, Hefei, 230601, Anhui, China.
| | - Sikui Liu
- School of Resources and Environmental Engineering, Anhui University, Anhui Province Engineering Laboratory for Mine Ecological Remediation, Hefei, 230601, Anhui, China
| | - Yeyu Chen
- School of Resources and Environmental Engineering, Anhui University, Anhui Province Engineering Laboratory for Mine Ecological Remediation, Hefei, 230601, Anhui, China
| | - Chang Li
- School of Resources and Environmental Engineering, Anhui University, Anhui Province Engineering Laboratory for Mine Ecological Remediation, Hefei, 230601, Anhui, China
| | - Jincheng Ni
- School of Resources and Environmental Engineering, Anhui University, Anhui Province Engineering Laboratory for Mine Ecological Remediation, Hefei, 230601, Anhui, China
| | - Yongchun Chen
- National Engineering Laboratory of Coal Mine Ecological Environment Protection, Huainan, 232001, Anhui, China
| | - Shikai An
- National Engineering Laboratory of Coal Mine Ecological Environment Protection, Huainan, 232001, Anhui, China
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Liu YR, Guo L, Yang Z, Xu Z, Zhao J, Wen SH, Delgado-Baquerizo M, Chen L. Multidimensional Drivers of Mercury Distribution in Global Surface Soils: Insights from a Global Standardized Field Survey. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:12442-12452. [PMID: 37506289 DOI: 10.1021/acs.est.3c04313] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2023]
Abstract
Soil stores a large amount of mercury (Hg) that has adverse effects on human health and ecosystem safety. Significant uncertainties still exist in revealing environmental drivers of soil Hg accumulation and predicting global Hg distribution owing to the lack of field data from global standardized analyses. Here, we conducted a global standardized field survey and explored a holistic understanding of the multidimensional environmental drivers of Hg accumulation in global surface soils. Hg content in surface soils from our survey ranges from 3.8 to 618.2 μg kg-1 with an average of 74.0 μg kg-1 across the globe. Atmospheric Hg deposition, particularly vegetation-induced elemental Hg0 deposition, is the major source of surface soil Hg. Soil organic carbon serves as the major substrate for sequestering Hg in surface soils and is significantly influenced by agricultural management, litterfall, and elevation. For human activities, changing land-use could be a more important contributor than direct anthropogenic emissions. Our prediction of a new global Hg distribution highlights the hot spots (high Hg content) in East Asia, the Northern Hemispheric temperate/boreal regions, and tropical areas, while the cold spots (low Hg content) are in arid regions. The holistic understanding of multidimensional environmental drivers helps to predict the Hg distribution in global surface soils under a changing global environment.
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Affiliation(s)
- 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
| | - Long Guo
- College of Resources and Environment and State Environmental Protection Key Laboratory of Soil Health and Green Remediation, Huazhong Agricultural University, Wuhan 430070, China
| | - Ziming Yang
- Department of Chemistry, Oakland University, Rochester, Michigan 48309, United States
| | - Zeng Xu
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, Shanghai 200241, China
| | - Jiating Zhao
- Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Shu-Hai Wen
- College of Resources and Environment and State Environmental Protection Key Laboratory of Soil Health and Green Remediation, Huazhong Agricultural University, Wuhan 430070, China
| | - Manuel Delgado-Baquerizo
- Laboratorio de Biodiversidad y Funcionamiento Ecosistemico, Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Sevilla 41012, Spain
- Unidad Asociada CSIC-UPO (BioFun), Universidad Pablo de Olavide, Sevilla 41013, Spain
| | - Long Chen
- Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, Shanghai 200241, China
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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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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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Nawab J, Ghani J, Rehman SAU, Idress M, Luqman M, Khan S, Asghar A, Rahman Z. Biomonitoring of mercury in water, sediments, and fish (brown and rainbow trout) from remote alpine lakes located in the Himalayas, Pakistan. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:81021-81036. [PMID: 35727512 DOI: 10.1007/s11356-022-21340-5] [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: 11/12/2021] [Accepted: 06/03/2022] [Indexed: 06/15/2023]
Abstract
Mercury (Hg) contamination of aquatic ecological units and subsequent bioaccumulation are major environmental problems of international scope. Moreover, the biogeochemistry of Hg in the remote alpine lakes aquatic ecosystem in the Himalayas remains largely unexplored. The current study investigated Hg concentrations in different environmental compartments such as water, fish, and sediments in the remote alpine lakes (RALs) including Glacial-fed Lake, Ice melting-fed Lake, and Rain-fed Lake in northern areas of Pakistan. The mean concentration of Hg in Rain-fed Lake water was (1.07 µg L-1), Ice melting-fed Lake (1.16 µg L-1), and Glacial-fed Lake (1.95 µg L-1). For fish muscle tissues, mean concentration of Hg was 1.02 mg kg-1 in the Rain-fed Lake, and 1.2 mg kg-1 for the Ice melting-fed Lake, and 1.51 mg kg-1 in the Glacial-fed Lake. Meanwhile, 0.27 mg kg-1 was observed for sediments in the Rain-fed Lake, 0.33 mg kg-1 for the Ice melting-fed Lake, and 0.38 mg kg-1 for the Glacial-fed Lake, respectively. Chronic daily intake (CDI) and potential health quotient (PHQ) for water showed high health risk in Glacial-fed Lake and low in Rain-fed Lake (PHQ < 1). The target hazard quotient (THQ) values for both the Brown and Rainbow trout in all the studied lakes water were less than 1, indicating no health risk. Furthermore, the Hg level showed high level of contamination in the sediments of all the studied lakes (190 ≤ RI < 380). Overall, Glacial-fed Lake water was more polluted with Hg, as compared to Rain-fed Lake and Ice melting-fed Lake. In the light of the abovementioned results, further research work is urgently needed to shed light on the biological and geochemical monitoring of Hg in arid high-altitude ecosystems along with source identification, mercury speciation, and other potential pollutants.
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Affiliation(s)
- Javed Nawab
- Department of Environmental Sciences, Kohat University of Science and Technology, Kohat, Pakistan.
- Department of Environmental Sciences, Abdul Wali Khan University Mardan, Mardan, Pakistan.
| | - Junaid Ghani
- Department of Biological, Geological and Environmental Sciences, Alma Mater Studiorum University of Bologna, 40126, Bologna, Italy
| | - Syed Aziz Ur Rehman
- Department of Environmental Sciences, University of Veterinary and Animal Sciences, Lahore, 54000, Punjab, Pakistan
| | - Muhammad Idress
- Department of Environmental Sciences, Abdul Wali Khan University Mardan, Mardan, Pakistan
| | - Muhammad Luqman
- Department of Environmental Sciences, University of Veterinary and Animal Sciences, Lahore, 54000, Punjab, Pakistan
| | - Sardar Khan
- Department of Environmental Sciences, University of Peshawar, Peshawar, 25120, Pakistan
| | - Ali Asghar
- Department of Environmental Sciences, Abdul Wali Khan University Mardan, Mardan, Pakistan
| | - Ziaur Rahman
- Department of Microbiology, Abdul Wali Khan University Mardan, Mardan, Pakistan
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Taylor VF, Landis JD, Janssen SE. Tracing the sources and depositional history of mercury to coastal northeastern U.S. lakes. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2022; 24:1805-1820. [PMID: 36065894 DOI: 10.1039/d2em00214k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Mercury (Hg) deposition was reconstructed in sediment cores from lakes in two coastal U.S. National Parks: Acadia National Park (ANP) and Cape Cod National Seashore (CCNS), to fill an important spatial gap in Hg deposition records and to explore changing sources of Hg and processes affecting Hg accumulation in these coastal sites. Recent Hg deposition chronology was assessed using (1) a newly developed lead-210 (210Pb) based sediment age model which employs 7Be to constrain deposition and sediment mixing of 210Pb-excess, (2) coinciding Pb flux and isotope ratios (206Pb/207Pb), and (3) Hg isotope ratios and their response to changes in Hg flux. At both sites, Hg flux increased substantially from pre-1850 levels, with accumulation in ANP peaking in the 1970s, whereas in CCNS, Hg levels were highest in recent sediments. Negative values of δ202Hg and Δ199Hg indicated terrestrially-derived Hg was a major constituent of Hg flux to Sargent Mountain Pond, ANP, although recent decreases in Hg flux were in agreement with precipitation Hg records, indicating a rapid watershed response. By contrast, δ202Hg and Δ199Hg profiles in Long Pond, CNNS reflect direct Hg deposition, but disturbances in the sedimentary record were indicated by bomb fallout radionuclide inventories and by peaks in both Pb and Hg isotope depth profiles. These cores provided poor reconstructions of atmospheric deposition and reveal responses that are decoupled from emissions reduction due to complex post-depositional redistribution of atmospheric metals including Hg. The application of multiple tracers of Hg deposition provide insight into the sources and pathways governing Hg accumulation in these lakes.
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Affiliation(s)
- Vivien F Taylor
- Department of Earth Science, 6105 Fairchild Hall, Dartmouth College, Hanover, NH 03755, USA.
| | - Joshua D Landis
- Department of Earth Science, 6105 Fairchild Hall, Dartmouth College, Hanover, NH 03755, USA.
| | - Sarah E Janssen
- U.S. Geological Survey Upper Midwest Water Science Center, Mercury Research Lab, 1 Gifford Pinchot Dr, Madison, WI 53726, USA
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11
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Lyman SN, Elgiar T, Gustin MS, Dunham-Cheatham SM, David LM, Zhang L. Evidence against Rapid Mercury Oxidation in Photochemical Smog. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:11225-11235. [PMID: 35877386 DOI: 10.1021/acs.est.2c02224] [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: 06/15/2023]
Abstract
Mercury pollution is primarily emitted to the atmosphere, and atmospheric transport and chemical processes determine its fate in the environment, but scientific understanding of atmospheric mercury chemistry is clouded in uncertainty. Mercury oxidation by atomic bromine in the Arctic and the upper atmosphere is well established, but less is understood about oxidation pathways in conditions of anthropogenic photochemical smog. Many have observed rapid increases in oxidized mercury under polluted conditions, but it has not been clearly demonstrated that these increases are the result of local mercury oxidation. We measured elemental and oxidized mercury in an area that experienced abundant photochemical activity (ozone >100 ppb) during winter inversion (i.e., cold air pools) conditions that restricted entrainment of air from the oxidized mercury-rich upper atmosphere. Under these conditions, oxidized mercury concentrations decreased day-upon-day, even as ozone and other pollutants increased dramatically. A box model that incorporated rapid kinetics for reactions of elemental mercury with ozone and OH radical overestimated observed oxidized mercury, while incorporation of slower, more widely accepted reaction rates did not. Our results show that rapid gas-phase mercury oxidation by ozone and OH in photochemical smog is unlikely.
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Affiliation(s)
- Seth N Lyman
- Bingham Research Center, Utah State University, Vernal, Utah 84078, United States
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322, United States
| | - Tyler Elgiar
- Bingham Research Center, Utah State University, Vernal, Utah 84078, United States
| | - Mae Sexauer Gustin
- Department of Natural Resources and Environmental Science, University of Nevada, Reno, Reno, Nevada 89557, United States
| | - Sarrah M Dunham-Cheatham
- Department of Natural Resources and Environmental Science, University of Nevada, Reno, Reno, Nevada 89557, United States
| | - Liji M David
- Bingham Research Center, Utah State University, Vernal, Utah 84078, United States
| | - Lei Zhang
- School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
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12
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Mason RP, Coulibaly M, Hansen G, Inman H, Myer PK, Yao KM. An examination of mercury levels in the coastal environment and fish of Cote d'Ivoire. CHEMOSPHERE 2022; 300:134609. [PMID: 35430197 DOI: 10.1016/j.chemosphere.2022.134609] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 04/04/2022] [Accepted: 04/11/2022] [Indexed: 06/14/2023]
Abstract
Artisanal and small-scale gold mining (ASGM), energy production and other industrial inputs are a major source of anthropogenic mercury (Hg) to the aquatic environment globally, and these inputs have led to environmental contamination and human exposure. While studies have documented the effects of Hg inputs to rivers and marine waters of the West African region, estuarine waters of Cote d'Ivoire have been understudied, besides the waters surrounding Abidjan. To fill this gap, and to examine the potential for human exposure to methylmercury (MeHg), we measured the concentrations of total Hg, MeHg, and ancillary parameters in water (dissolved and particulate phases), sediment and fish to determine the extent of environmental impact and the potential for MeHg exposure for people consuming these fish. Levels of Hg and MeHg in sediment were elevated in the vicinity of the urban environment (up to 0.3 ng/g dry weight (dw) MeHg and 623 ng/g dw total Hg) and lowest in the more remote estuarine environments. Measurements of Hg in tuna and other larger pelagic coastal species indicated that levels were elevated but comparable to other North Atlantic regions. However, levels of Hg in fish, even smaller estuarine species, were such that the rural and urban populations are potentially being exposed to unsafe levels of MeHg, primarily as a result of the relatively high fish consumption in Cote d'Ivoire compared to other countries. Overall, both local point sources and the transport of Hg used in interior ASGM activities are the sources for Hg contamination to these coastal waters.
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Affiliation(s)
- R P Mason
- Department of Marine Sciences, University of Connecticut, Groton, CT, USA.
| | - M Coulibaly
- Ecole Normale Superieure (ENS), Abidjan, Cote d'Ivoire
| | - G Hansen
- Department of Marine Sciences, University of Connecticut, Groton, CT, USA
| | - H Inman
- Department of Marine Sciences, University of Connecticut, Groton, CT, USA
| | - P K Myer
- Department of Marine Sciences, University of Connecticut, Groton, CT, USA
| | - K M Yao
- Oceanographic Institute, Abidjan, Cote d'Ivoire
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13
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Sun R, Hintelmann H, Wiklund JA, Evans MS, Muir D, Kirk JL. Mercury Isotope Variations in Lake Sediment Cores in Response to Direct Mercury Emissions from Non-Ferrous Metal Smelters and Legacy Mercury Remobilization. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:8266-8277. [PMID: 35616385 DOI: 10.1021/acs.est.2c02692] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Nature archives record atmospheric mercury (Hg) depositions from directly emitted Hg and re-emitted legacy Hg. Tracing the legacy versus newly deposited Hg is still, however, challenging. Here, we measured Hg isotope compositions in three dated sediment cores at different distances from the Flin Flon smelter, the largest Canadian Hg sources to the atmosphere during the 1930s-2000s. During the smelter's operative period, Hg isotope compositions showed limited variations in the near-field lake (<10 km) sediments but were rather variable in middle- (20-75 km) and far-field lake (∼800 km) sediments. Only the post-2000 sediments in middle/far-field lakes showed significantly negative Hg isotope shifts, while sediments from the 1970s-1990s had Hg isotope values resembling those of near-field lake post-1930 sediments. We suggest that the smelter's peak Hg emissions during the 1970s-1990s, which coincided with the deployment of a super stack in the mid-1970s, largely increased the long-range dispersion of smelter plumes. For the top post-2000 sediments, the fugitive dust from ore tailings and terrestrial legacy Hg re-emissions dominated Hg deposition in near-field lakes and middle/far-field lakes, respectively. Our study demonstrates that legacy Hg remobilization now exports substantial amounts of Hg to ecosystems, highlighting the need for aggressive remediation measures of Hg-contaminated sites.
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Affiliation(s)
- Ruoyu Sun
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
- Water Quality Centre, Trent University, Peterborough, Ontario K9J 7B8, Canada
| | - Holger Hintelmann
- Water Quality Centre, Trent University, Peterborough, Ontario K9J 7B8, Canada
| | - Johan A Wiklund
- Aquatic Contaminants Research Division, Environment and Climate Change Canada, Burlington, Ontario L7R 4A6, Canada
| | - Marlene S Evans
- Watershed Hydrology and Ecology Research Division, Environment and Climate Change Canada, Saskatoon, Saskatchewan S7N 3H5, Canada
| | - Derek Muir
- Aquatic Contaminants Research Division, Environment and Climate Change Canada, Burlington, Ontario L7R 4A6, Canada
| | - Jane L Kirk
- Aquatic Contaminants Research Division, Environment and Climate Change Canada, Burlington, Ontario L7R 4A6, Canada
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14
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Cossa D, Knoery J, Bănaru D, Harmelin-Vivien M, Sonke JE, Hedgecock IM, Bravo AG, Rosati G, Canu D, Horvat M, Sprovieri F, Pirrone N, Heimbürger-Boavida LE. Mediterranean Mercury Assessment 2022: An Updated Budget, Health Consequences, and Research Perspectives. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:3840-3862. [PMID: 35244390 DOI: 10.1021/acs.est.1c03044] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Mercury (Hg) and especially its methylated species (MeHg) are toxic chemicals that contaminate humans via the consumption of seafood. The most recent UNEP Global Mercury Assessment stressed that Mediterranean populations have higher Hg levels than people elsewhere in Europe. The present Critical Review updates current knowledge on the sources, biogeochemical cycling, and mass balance of Hg in the Mediterranean and identifies perspectives for future research especially in the context of global change. Concentrations of Hg in the Western Mediterranean average 0.86 ± 0.27 pmol L-1 in the upper water layer and 1.02 ± 0.12 pmol L-1 in intermediate and deep waters. In the Eastern Mediterranean, Hg measurements are in the same range but are too few to determine any consistent oceanographical pattern. The Mediterranean waters have a high methylation capacity, with MeHg representing up to 86% of the total Hg, and constitute a source of MeHg for the adjacent North Atlantic Ocean. The highest MeHg concentrations are associated with low oxygen water masses, suggesting a microbiological control on Hg methylation, consistent with the identification of hgcA-like genes in Mediterranean waters. MeHg concentrations are twice as high in the waters of the Western Basin compared to the ultra-oligotrophic Eastern Basin waters. This difference appears to be transferred through the food webs and the Hg content in predators to be ultimately controlled by MeHg concentrations of the waters of their foraging zones. Many Mediterranean top-predatory fish still exceed European Union regulatory Hg thresholds. This emphasizes the necessity of monitoring the exposure of Mediterranean populations, to formulate adequate mitigation strategies and recommendations, without advising against seafood consumption. This review also points out other insufficiencies of knowledge of Hg cycling in the Mediterranean Sea, including temporal variations in air-sea exchange, hydrothermal and cold seep inputs, point sources, submarine groundwater discharge, and exchanges between margins and the open sea. Future assessment of global change impacts under the Minamata Convention Hg policy requires long-term observations and dedicated high-resolution Earth System Models for the Mediterranean region.
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Affiliation(s)
- Daniel Cossa
- Université Grenoble Alpes, ISTerre, CS 40700, 38058 Grenoble Cedex 9, France
| | - Joël Knoery
- Ifremer, Centre Atlantique de Nantes, BP 44311, 44980 Nantes, France
| | - Daniela Bănaru
- Aix Marseille Université, CNRS/INSU, Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, 13288 Marseille, France
| | - Mireille Harmelin-Vivien
- Aix Marseille Université, CNRS/INSU, Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, 13288 Marseille, France
| | - Jeroen E Sonke
- Géosciences Environnement Toulouse, CNRS/Observatoire Midi-Pyrénées (OMP)/Université de Toulouse, 31400 Toulouse, France
| | - Ian M Hedgecock
- Istituto sull'inquinamento atmosferico, CNR-IIA, 87036 Rende, Italy
| | | | - Ginevra Rosati
- Istituto Nazionale di Oceanografia e di Geofisca Sperimentale (OGS), 34010 Trieste, Italy
| | - Donata Canu
- Istituto Nazionale di Oceanografia e di Geofisca Sperimentale (OGS), 34010 Trieste, Italy
| | | | | | - Nicola Pirrone
- Istituto sull'inquinamento atmosferico, CNR-IIA, 87036 Rende, Italy
| | - Lars-Eric Heimbürger-Boavida
- Aix Marseille Université, CNRS/INSU, Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, 13288 Marseille, France
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15
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Cooke CA, Curtis JH, Kenney WF, Drevnick P, Siegel PE. Caribbean Lead and Mercury Pollution Archived in a Crater Lake. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:1736-1742. [PMID: 35034441 DOI: 10.1021/acs.est.1c06791] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Lead and mercury have long histories of anthropogenic use and release to the environment extending into preindustrial times. Yet, the timing, magnitude, and persistence of preindustrial emissions remain enigmatic, especially for mercury. Here, we quantify tropical lead and mercury deposition over the past ∼3000 years using a well-dated sediment core from a small crater lake (Lake Antoine, Grenada). Preindustrial increases in lead and mercury concentrations can be explained by varying inputs of watershed mineral and organic matter, which in turn reflect climate-driven changes in the lake level. We find no evidence that preindustrial lead and mercury use raised deposition rates in this remote ecosystem, and our results underscore the need to carefully evaluate common normalization approaches for changing lithogenic inputs and sedimentation rates. Industrial-era lead and mercury accumulation rates in Lake Antoine have been accelerated by land use and land cover change within the crater rim, yet global industrial pollution remains evident. After correcting for watershed inputs, we find that recent atmospheric lead and mercury deposition rates averaged 2925 and 24 μg/m2/y, respectively, which are in close agreement with monitoring data. Our results challenge recent assessments suggesting preindustrial mercury use raised atmospheric deposition rates globally, highlighting the unique nature of 20th Century industrial pollution.
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Affiliation(s)
- Colin A Cooke
- Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta T6G 2E3, Canada
- Environment and Parks, Government of Alberta, Edmonton, Alberta T5J 5C6, Canada
| | - Jason H Curtis
- Department of Geological Sciences, University of Florida, Gainesville, Florida 32611, United States
| | - William F Kenney
- Land Use and Environmental Change Institute, University of Florida, Gainesville, Florida 32611, United States
| | - Paul Drevnick
- Environment and Parks, Government of Alberta, Calgary, Alberta T2L 2K8, Canada
| | - Peter E Siegel
- Department of Anthropology, Montclair State University, Montclair, New Jersey 07043, United States
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17
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Evidence that Pacific tuna mercury levels are driven by marine methylmercury production and anthropogenic inputs. Proc Natl Acad Sci U S A 2022; 119:2113032119. [PMID: 34983875 PMCID: PMC8764691 DOI: 10.1073/pnas.2113032119] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/02/2021] [Indexed: 01/17/2023] Open
Abstract
Pacific Ocean tuna is among the most-consumed seafood products but contains relatively high levels of the neurotoxin methylmercury. Limited observations suggest tuna mercury levels vary in space and time, yet the drivers are not well understood. Here, we map mercury concentrations in skipjack tuna across the Pacific Ocean and build generalized additive models to quantify the anthropogenic, ecological, and biogeochemical drivers. Skipjack mercury levels display a fivefold spatial gradient, with maximum concentrations in the northwest near Asia, intermediate values in the east, and the lowest levels in the west, southwest, and central Pacific. Large spatial differences can be explained by the depth of the seawater methylmercury peak near low-oxygen zones, leading to enhanced tuna mercury concentrations in regions where oxygen depletion is shallow. Despite this natural biogeochemical control, the mercury hotspot in tuna caught near Asia is explained by elevated atmospheric mercury concentrations and/or mercury river inputs to the coastal shelf. While we cannot ignore the legacy mercury contribution from other regions to the Pacific Ocean (e.g., North America and Europe), our results suggest that recent anthropogenic mercury release, which is currently largest in Asia, contributes directly to present-day human mercury exposure.
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18
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Milić D, Bubanja N, Ninkov J, Milić S, Vasin J, Luković J. Phytoremediation potential of the naturally occurring wetland species in protected Long Beach in Ulcinj, Montenegro. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 797:148995. [PMID: 34303239 DOI: 10.1016/j.scitotenv.2021.148995] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 07/06/2021] [Accepted: 07/08/2021] [Indexed: 06/13/2023]
Abstract
Long Beach, situated in southern Montenegro, is subject to considerable biogenic and abiogenic influences. Thus, analyzing total heavy metal content in soil and plants in this region is, while challenging, highly important in order to assess the level for determining the soil degradation level and the phytoremediation potential of naturally growing salt marsh species. This area together with a Bojana river and backshore forms a real vegetation mosaic where habitats of various types coexist. Therefore, it represents good model system. In the present study, the levels of As, Al, B, Cd, Co, Cr, Cu, Hg, Fe, Mn, Mo, Ni, Pb and Zn in coastal soils as well as in eight salt marsh plants: Bolboschoenus maritimus, Juncus acutus, Juncus anceps, Juncus articulatus, Juncus gerardii, Juncus maritimus, Scirpus holoschoenus and Schoenus nigricans, were investigated in order to identify the plant species that can be used for the remediation of polluted sites, especially those located along the coastline. The obtained results show that species J. gerardii, J. articulatus and B. maritimus can be clearly separated from J. acutus, J. anceps, J. maritimus, S. holoschoenus and Sh. nigricans based on the degree of heavy metal accumulation in various organs. Moreover, analyses revealed that the bioaccumulation factor of underground organs is significantly higher relative to that of the aboveground parts for almost all investigated metals and species. The bioaccumulation factor had the highest value in the underground organs of J. gerardii and B. maritimus, where a value of 3.37 was measured for B and 2.54 for Hg, respectively. Hence, as all investigated species are "underground accumulators" for most of the analyzed metals, they could be useful for phytostabilization and phytoremediation of B and Hg in particular. Moreover, each plant species can be used in the phytoremediation process targeting specific heavy metals.
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Affiliation(s)
- Dubravka Milić
- University of Novi Sad, Faculty of Sciences, Department of Biology and Ecology, Trg Dositeja Obradovica 2, Novi Sad 21000, Serbia.
| | - Nada Bubanja
- Natural History Museum of Montenegro, Trg Vojvode Bećir Bega Osmanagića 16, Podgorica, Montenegro.
| | - Jordana Ninkov
- Institute of Field and Vegetable Crops, Maksima Gorkog 30, 21000 Novi Sad, Serbia.
| | - Stanko Milić
- Institute of Field and Vegetable Crops, Maksima Gorkog 30, 21000 Novi Sad, Serbia.
| | - Jovica Vasin
- Institute of Field and Vegetable Crops, Maksima Gorkog 30, 21000 Novi Sad, Serbia.
| | - Jadranka Luković
- University of Novi Sad, Faculty of Sciences, Department of Biology and Ecology, Trg Dositeja Obradovica 2, Novi Sad 21000, Serbia.
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Malcata Martins B, O'Driscoll NJ, Mallory ML, Canário J. A Review of Freshwater Invertebrates as Biomonitors of Methylmercury: the Importance of More Complete Physical and Chemical Reporting. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2021; 107:801-808. [PMID: 34081149 DOI: 10.1007/s00128-021-03274-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 05/20/2021] [Indexed: 06/12/2023]
Abstract
Methylmercury (MeHg) is a toxic and bioaccumulative organo-metallic compound that is naturally produced in many ecosystems. Organisms that occupy the lower trophic positions in food webs may be key factors in the assessment of MeHg biomagnification between ecosystems. Here we present a review of the peer-reviewed literature examining MeHg bioaccumulation in freshwater invertebrates, focused principally on insects. This review aims to characterize the invertebrates that bioaccumulate higher MeHg concentrations and therefore pose a higher risk to upper trophic levels and to clarify which ecosystems are more susceptible to bioaccumulation in lower trophic levels. However, we found that few studies provided robust environmental data (notably water chemistry) as part of their papers, dramatically limiting our ability to test for factors that might contribute to different concentrations of MeHg in invertebrates. We highlight the importance of providing physical and chemical characteristics of study sites in publications examining MeHg bioaccumulation and biomagnification. Adopting the proposed recommendations will improve the available information for future mercury risk assessment analyses.
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Affiliation(s)
- Beatriz Malcata Martins
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001, Lisboa, Portugal.
| | - Nelson J O'Driscoll
- Department of Earth and Environmental Science, K.C. Irving Environmental Science Center, Acadia University, Wolfville, NS, B4P 2R6, Canada
| | - Mark L Mallory
- Department of Biology, Acadia University, Wolfville, NS, B4P 2R6, Canada
| | - João Canário
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001, Lisboa, Portugal
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Li C, Shen J, Zhang J, Lei P, Kong Y, Zhang J, Tang W, Chen T, Xiang X, Wang S, Zhang W, Zhong H. The silver linings of mercury: Reconsideration of its impacts on living organisms from a multi-timescale perspective. ENVIRONMENT INTERNATIONAL 2021; 155:106670. [PMID: 34090260 DOI: 10.1016/j.envint.2021.106670] [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: 03/16/2021] [Revised: 04/28/2021] [Accepted: 05/24/2021] [Indexed: 06/12/2023]
Abstract
Research on mercury (Hg), a naturally occurring element in Earth's lithosphere, has been extremely hot in the past few decades due to the outbreak of a series of disastrous poisoning incidents. However, such studies might provide us a biased view towards Hg if no thorough review about its long-term effects on living organisms from a multi-timescale perspective was performed. Hg might have played a mysterious role in critical intervals (e.g., mass extinction and oceanic anoxia events) in several geologic periods due to the elevated Hg levels induced by volcanism whereas it has long been used for various purposes in human history. Therefore, it is necessary to go through previous studies and historical records of different timescales (100 to 106 yr). In this work, we conducted a thorough review of Hg knowledge at three different timescales, i.e., geologic periods (106 yr), human history (103 yr), and contemporary history (100 yr), summarizing recent advances and indicated potential research gaps. By doing so, we demonstrated that it is possible to achieve safe and sustainable Hg applications despite the current Hg crisis. However, such silver linings depend on a better understanding of ecosystem dynamics. Besides, considering the possible dire consequences of erupted Hg levels as suggested in geological periods, swift actions to mitigate the impacts of anthropogenic activities on the Hg cycle will be another key point. Overall, this review presented a unique perspective of Hg combining different timescales, shedding light on the importance of a better understanding of the global ecosystem as a whole and maintaining the sustainability of planet Earth in the future.
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Affiliation(s)
- Chengjun Li
- Institute of Environmental Research at Greater Bay Area, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Jun Shen
- State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, Hubei 430074, China
| | - Jin Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Pei Lei
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Yaqi Kong
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Jichao Zhang
- Institute of Environmental Research at Greater Bay Area, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Wenli Tang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Tianyu Chen
- School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China
| | - Xin Xiang
- School of Information Management, Nanjing University, Nanjing 210023, China
| | - Shuxiao Wang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Wei Zhang
- Institute of Environmental Research at Greater Bay Area, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China.
| | - Huan Zhong
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China; Environmental and Life Sciences Program (EnLS), Trent University, Peterborough, Ontario, Canada.
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21
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Panagos P, Jiskra M, Borrelli P, Liakos L, Ballabio C. Mercury in European topsoils: Anthropogenic sources, stocks and fluxes. ENVIRONMENTAL RESEARCH 2021; 201:111556. [PMID: 34171371 PMCID: PMC8503384 DOI: 10.1016/j.envres.2021.111556] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 06/10/2021] [Accepted: 06/16/2021] [Indexed: 05/29/2023]
Abstract
Mercury (Hg) is one of the most dangerous pollutants worldwide. In the European Union (EU), we recently estimated the Hg distribution in topsoil using 21,591 samples and a series of geo-physical inputs. In this manuscript, we investigate the impact of mining activities, chrol-alkali industries and other diffuse pollution sources as primary anthropogenic sources of Hg hotspots in the EU. Based on Hg measured soil samples, we modelled the Hg pool in EU topsoils, which totals about 44.8 Gg, with an average density of 103 g ha-1. As a following step, we coupled the estimated Hg stocks in topsoil with the pan-European assessment of soil loss due to water erosion and sediment distribution. In the European Union and UK, we estimated that about 43 Mg Hg yr-1 are displaced by water erosion and c. a. 6 Mg Hg yr-1 are transferred with sediments to river basins and eventually released to coastal Oceans. The Mediterranean Sea receives almost half (2.94 Mg yr-1) of the Hg fluxes to coastal oceans and it records the highest quantity of Hg sediments. This is the result of elevated soil Hg concentration and high erosion rates in the catchments draining into the Mediterranean Sea. This work contributes to new knowledge in support of the policy development in the EU on the Zero Pollution Action Plan and the Sustainable Development Goal (SDGs) 3.9 and 14.1, which both have as an objective to reduce soil pollution by 2030.
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Affiliation(s)
- Panos Panagos
- European Commission, Joint Research Centre (JRC), Ispra, Italy.
| | - Martin Jiskra
- Environmental Geosciences, University of Basel, Switzerland
| | - Pasquale Borrelli
- Department of Earth and Environmental Sciences, University of Pavia, 27100, Pavia, Italy
| | - Leonidas Liakos
- European Commission, Joint Research Centre (JRC), Ispra, Italy
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Yevugah LL, Darko G, Bak J. Does mercury emission from small-scale gold mining cause widespread soil pollution in Ghana? ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 284:116945. [PMID: 33906042 DOI: 10.1016/j.envpol.2021.116945] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 03/10/2021] [Accepted: 03/11/2021] [Indexed: 06/12/2023]
Abstract
The use of mercury in small-scale gold mining is globally the largest anthropogenic source of mercury in the environment. In countries like Ghana, where small-scale gold mining is a highly important economic sector, the activity is also expected to cause local pollution. This study is based on a hypothesis that the mining activity in Ghana is causing more widespread soil pollution also outside active mining sites, and that the main part of regional differences in soil concentrations of mercury might come from pollution. Little systematic and dependable data has been collected to assess the extent of mercury contamination of soils in areas outside active mining areas. The regional aspect of mercury pollution from mining has not been studied in Ghana or other countries with a large small-scale gold mining sector. Systematic collection of soil samples on a 25 × 25 km2 net covering the entire country was carried out to ensure the representativeness of data and to allow calculation of spatial trends. The soil concentrations found in one-third of the country, where most intensive mining takes place, are three times higher than concentrations in the rest of the country. This difference cannot be explained by sources of natural variation in mercury concentrations but can be explained by decades of atmospheric deposition. It is therefore likely that the mining activity has caused a more widespread increase in soil concentrations, also outside active mining sites. The mercury concentrations found are on average 0.024 mg kg-1, which is low compared to published studies from other countries and regions and estimated world averages. All measured concentrations are well below soil quality criteria for human health. The build-up of soil concentrations in the mining area is still problematic because mercury is a hazardous substance in the environment.
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Affiliation(s)
- Lily Lisa Yevugah
- Department of Geomatic Engineering, College of Engineering. Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Godfred Darko
- Department of Chemistry, College of Science. Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Jesper Bak
- Aarhus University, Department of Bioscience, Velsoevej 25, 8600, Silkeborg, Denmark.
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Chronological Trends and Mercury Bioaccumulation in an Aquatic Semiarid Ecosystem under a Global Climate Change Scenario in the Northeastern Coast of Brazil. Animals (Basel) 2021; 11:ani11082402. [PMID: 34438859 PMCID: PMC8388643 DOI: 10.3390/ani11082402] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/03/2021] [Accepted: 08/09/2021] [Indexed: 11/17/2022] Open
Abstract
Simple Summary Managing aquatic systems is becoming increasingly complex due to human impacts, multiple and competing water needs and climate variability. Considering the Hg concentration present in the top layers of sediment (~20 cm around 30 to 40 years) with the outer layers in the tree cores tree rings cores and in the sediment’s cores from Pacoti estuary and the Ceará estuary, overall data indicate an increase in mercury in recent years. A positive and significant correlation (p < 0.05) was revealed between Hg trends in sediments and Hg trends in annular tree rings. This shared Hg pattern reflects local environmental conditions. The results of this work reinforce the indicators previously described in the semiarid NE region of Brazil, showing that global climate change and some anthropogenic factors are key drivers to Hg exposure and biomagnification for wildlife and humans. Possible climate-induced shifts in these aquatic systems highlight the need for accurate and regionally specific metrics of change in the past in response to climate and for improved understanding of response to climate factors. These processes are inducing a greater mobilization of bioavailable Hg, which could allow an acceleration of the biogeochemical transformation of Hg. Abstract Due to global warming, in the northeastern semiarid coastal regions of Brazil, regional and global drivers are responsible for decreasing continental runoff and increasing estuarine water residence time, which promotes a greater mobilization of bioavailable mercury (Hg) and allows increasing fluxes and/or bioavailability of this toxic trace element and an acceleration of biogeochemical transformation of Hg. In this work, an application of dendrochemistry analysis (annular tree rings analysis) was developed for the reconstruction of the historical pattern of mercury contamination in a contaminated area, quantifying chronological Hg contamination trends in a tropical semiarid ecosystem (Ceará River Estuary, northeastern coast of Brazil) through registration of mercury concentration on growth rings in specimens of Rhizophora mangle L. and using the assessment in sediments as a support for the comparison of profiles of contamination. The comparison with sediments from the same place lends credibility to this type of analysis, as well as the relationship to the historical profile of contamination in the region, when compared with local data about industries and ecological situation of sampling sites. In order to evaluate the consequences of the described increase in Hg bioavailability and bioaccumulation in aquatic biota, and to assess the biological significance of Hg concentrations in sediments to fish and wildlife, muscle and liver from a bioindicator fish species, S. testudineus, were also analyzed. The results of this work reinforce the indicators previously described in the semiarid NE region of Brazil, which showed that global climate change and some anthropogenic factors are key drivers of Hg exposure and biomagnification for wildlife and humans. Considering the Hg concentration present in the top layers of sediment (~20 cm around 15 to 20 years) with the outer layers in the tree ring cores and in the sediment’s cores from Pacoti estuary and the Ceará estuary, overall the data indicate an increase in mercury in recent years in the Hg surface sediments, especially associated with the fine sediment fraction, mainly due to the increased capacity of small particles to adsorb Hg. There was revealed a positive and significant correlation (p < 0.05) between Hg trends in sediments and Hg trends in annular tree rings. This shared Hg pattern reflects local environmental conditions. The Hg concentration values in S. testudineus from both study areas are not restrictive to human consumption, being below the legislated European limit for Hg in foodstuffs. The results from S. testudineus muscles analysis suggest a significant and linear increase in Hg burden with increasing fish length, indicating that the specimens are accumulating Hg as they grow. The results from both rivers show an increase in BSAF with fish growth. The [Hg] liver/[Hg] muscles ratio >1, which indicates that the S. testudineus from both study areas are experiencing an increase in Hg bioavailability. Possible climate-induced shifts in these aquatic systems processes are inducing a greater mobilization of bioavailable Hg, which could allow an acceleration of the biogeochemical transformation of Hg.
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24
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Wang X, Yuan W, Lin CJ, Wu F, Feng X. Stable mercury isotopes stored in Masson Pinus tree rings as atmospheric mercury archives. JOURNAL OF HAZARDOUS MATERIALS 2021; 415:125678. [PMID: 33765566 DOI: 10.1016/j.jhazmat.2021.125678] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 02/28/2021] [Accepted: 03/14/2021] [Indexed: 06/12/2023]
Abstract
The accuracy of mercury (Hg) dendrochemistry has been questioned because significant knowledge gaps exist in understanding the Hg translocation and mobility in tree-ring. In this study, we evaluated Hg concentrations and isotopic profiles in the tree-ring at a Hg artisanal mining site and a control site with the documented local Hg production inventory. Results show that the Hg concentration accumulated in tree-ring fails to reconstruct the temporal trend of Hg production due to confounded tree physiological and environmental factors, specifically, the radial translocation and tree age effects occurring during the fast-growing period. The temporal profiles of δ202Hg exhibit pronounced tree-specific variabilities due to the complexity of Hg isotopic mass dependent fractionation during atmospheric Hg uptake and translocation in vegetation. The Hg odd-MIF (mass independent fractionation) profiles in tree-ring can reconstruct a decadal-scale temporal trend of the atmospheric Hg0 pollution level, and also be used as a tracer to distinguish the emission source shifts of atmospheric Hg0. However, the radial translocation would result in uncertainties at the higher resolution because of the mixing of odd-MIF signatures with active rings. Caution should be taken and additional supporting evidence collected from independent methods should be used for verifying the tree-ring records.
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Affiliation(s)
- Xun Wang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; College of Resources and Environment, Southwest University, Chongqing 400715, China.
| | - Wei Yuan
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Che-Jen Lin
- Center for Advances in Water and Air Quality, Lamar University, Beaumont 77710, USA; Department of Civil and Environmental Engineering, Lamar University, Beaumont 77710, USA
| | - Fei Wu
- Key Laboratory for Information System of Mountainous Area and Protection of Ecological Environment of Guizhou Province, Guizhou Normal University, Guiyang 550001, China
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; Center for Excellence in Quaternary Science and Global Change, Chinese Academy of Sciences, Xian 710061, China.
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25
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Mercury contamination of seabird and sea duck eggs from high Arctic Greenland. Polar Biol 2021. [DOI: 10.1007/s00300-021-02864-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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26
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Corella JP, Sierra MJ, Garralón A, Millán R, Rodríguez-Alonso J, Mata MP, de Vera AV, Moreno A, González-Sampériz P, Duval B, Amouroux D, Vivez P, Cuevas CA, Adame JA, Wilhelm B, Saiz-Lopez A, Valero-Garcés BL. Recent and historical pollution legacy in high altitude Lake Marboré (Central Pyrenees): A record of mining and smelting since pre-Roman times in the Iberian Peninsula. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 751:141557. [PMID: 32882549 DOI: 10.1016/j.scitotenv.2020.141557] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 08/05/2020] [Accepted: 08/05/2020] [Indexed: 06/11/2023]
Abstract
We have analyzed potential harmful trace elements (PHTE; Pb, Hg, Zn, As and Cu) on sediment cores retrieved from lake Marboré (LM) (2612 m a.s.l, 42°41'N; 0° 2'E). PHTE variability allowed us to reconstruct the timing and magnitude of trace metal pollutants fluxes over the last 3000 years in the Central Pyrenees. A statistical treatment of the dataset (PCA) enabled us to discern the depositional processes of PHTE, that reach the lake via direct atmospheric deposition. Indeed, the location of LM above the atmospheric boundary layer makes this lake an exceptional site to record the long-range transport of atmospheric pollutants in the free troposphere. Air masses back-trajectories analyses enabled us to understand the transport pathways of atmospheric pollutants while lead isotopic analyses contributed to evaluate the source areas of metal pollution in SW Europe during the Late Holocene. PHTE variability, shows a clear agreement with the main exploitation phases of metal resources in Southern Europe during the Pre-Industrial Period. We observed an abrupt lead enrichment from 20 to 375 yrs CE mostly associated to silver and lead mining and smelting practices in Southern Iberia during the Roman Empire. This geochemical data suggests that regional atmospheric metal pollution during the Roman times rivalled the Industrial Period. PHTE also increased during the High and Late Middle Ages (10-15th centuries) associated to a reactivation of mining and metallurgy activities in high altitude Pyrenean mining sites during climate amelioration phases. Atmospheric mercury deposition in the Lake Marboré record mostly reflects global emissions, particularly from Almadén mines (central Spain) and slightly fluctuates during the last three millennia with a significant increase during the last five centuries. Our findings reveal a strong mining-related pollution legacy in alpine lakes and watersheds that needs to be considered in management plans for mountain ecosystems as global warming and human pressure effects may contribute to their future degradation.
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Affiliation(s)
- J P Corella
- Universite Grenoble Alpes, CNRS, IRD, IGE, 38000 Grenoble, France; CIEMAT - Environmental Department (DMA), Avenida Complutense 40, E-28040 Madrid, Spain.
| | - M J Sierra
- CIEMAT - Environmental Department (DMA), Avenida Complutense 40, E-28040 Madrid, Spain
| | - A Garralón
- CIEMAT - Environmental Department (DMA), Avenida Complutense 40, E-28040 Madrid, Spain
| | - R Millán
- CIEMAT - Environmental Department (DMA), Avenida Complutense 40, E-28040 Madrid, Spain
| | - J Rodríguez-Alonso
- CIEMAT - Environmental Department (DMA), Avenida Complutense 40, E-28040 Madrid, Spain
| | - M P Mata
- Instituto Geológico y Minero de España, Rios Rosas 23, 28003 Madrid, Spain
| | - A Vicente de Vera
- Pyrenean Institute of Ecology, CSIC, Avda Montañana 1005, 50059 Zaragoza, Spain
| | - A Moreno
- Pyrenean Institute of Ecology, CSIC, Avda Montañana 1005, 50059 Zaragoza, Spain
| | - P González-Sampériz
- Pyrenean Institute of Ecology, CSIC, Avda Montañana 1005, 50059 Zaragoza, Spain
| | - B Duval
- Universite de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, Institut des Sciences Analytiques et de Physico-chimie pour l'Environnement et les matériaux, Pau, France, 64000 Pau, France
| | - D Amouroux
- Universite de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, Institut des Sciences Analytiques et de Physico-chimie pour l'Environnement et les matériaux, Pau, France, 64000 Pau, France
| | - P Vivez
- Centro de Estudios de Sobrarbe, Sociedad Española para la Defensa del Patrimonio Geológico Y Minero, Plaza España, 22340 Boltaña, Huesca, Spain
| | - C A Cuevas
- Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Rocasolano, CSIC, Serrano 119, 28006 Madrid, Spain
| | - J A Adame
- Atmospheric Sounding Station, El Arenosillo Observatory, Atmospheric Research and Instrumentation Branch, National Institute for Aerospace Technology (INTA), Mazagón, Huelva, Spain
| | - B Wilhelm
- Universite Grenoble Alpes, CNRS, IRD, IGE, 38000 Grenoble, France
| | - A Saiz-Lopez
- Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Rocasolano, CSIC, Serrano 119, 28006 Madrid, Spain
| | - B L Valero-Garcés
- Pyrenean Institute of Ecology, CSIC, Avda Montañana 1005, 50059 Zaragoza, Spain
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27
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Carvalho F, Schulte L. Reconstruction of mining activities in the Western Alps during the past 2500 years from natural archives. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 750:141208. [PMID: 32846252 DOI: 10.1016/j.scitotenv.2020.141208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 07/21/2020] [Accepted: 07/21/2020] [Indexed: 06/11/2023]
Abstract
The geochemical analysis of natural archives can improve our knowledge of past mining activities and their environmental imprint. The sedimentary records from the Hasli-Aare floodplain (Bernese Alps) over the last 2500 years were analysed for metals. Evidence of past mining contamination was obtained from the XRF analyses of iron, copper, zinc and lead. These results were analytically and statistically processed to produce a metal content index. Positive metal anomalies indicate four major pulses of contamination coinciding with the end of the Iron Age, from the end of the Roman Period to the Early Medieval Period, the Late Medieval Period, and the Modern Period. These pulses show good agreement with local historical sources of mining in the Hasli-Aare catchment, dating back to the beginning of the 15th century. Furthermore, they are in phase with anthropogenic pollution trends inferred from glacier ice cores, lake sediments and peat bogs across the Western Alps, most notably during the Roman, Late Medieval and Modern Periods. However, close comparison between these records can show some differences, suggesting local variations in mining activities and/or a lag in metal transfer. The reconstructed periods of anthropogenic metal pollution are located in their political, economic and social contexts and compared with the climate periods of central Europe.
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Affiliation(s)
- F Carvalho
- FluvAlps Research Group, Department of Geography, University of Barcelona, Spain.
| | - L Schulte
- FluvAlps Research Group, Department of Geography, University of Barcelona, Spain
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28
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Rosati G, Solidoro C, Canu D. Mercury dynamics in a changing coastal area over industrial and postindustrial phases: Lessons from the Venice Lagoon. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 743:140586. [PMID: 32659553 DOI: 10.1016/j.scitotenv.2020.140586] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 06/25/2020] [Accepted: 06/26/2020] [Indexed: 06/11/2023]
Abstract
During the industrial period, significant amounts of mercury (Hg) were discharged into the Venice Lagoon. Here, a spatially explicit model was implemented to reconstruct the temporal evolution of the total mercury (HgT) and methylmercury (MeHgT) concentrations in lagoon water and sediments over two centuries (1900-2100), from preindustrial to postindustrial phases. The model simulates the transport and transformations of particulate and dissolved Hg species. It is forced with time-variable Hg inputs and environmental conditions, including scenarios of future atmospheric deposition, reconstructed according to local and global socioeconomic scenarios. Since 1900, ~36 Mg of HgT and ~380 kg of MeHgT were delivered to the lagoon, and stored in the sediments. The deposition of Hg from the water to the seafloor increased during a period of eutrophication (1980s); however, the reverse fluxes increased during a period of high sediment resuspension caused by the unregulated fishing of Manila clams (1990s). In the current postindustrial phase, the lagoon sediments have acted as a secondary source to the lagoon waters, delivering Hg (~38 kg y-1) and MeHg (~0.07 kg y-1). The MeHg inputs from the watershed (~0.28 kg y-1) appear to be higher than the secondary fluxes from the sediments. The estimated HgT export to the Adriatic Sea is ~56 kg y-1. Since HgT and MeHgT outputs slightly exceed inputs, the concentrations are slowly decreasing. While the decreasing trend is maintained in all scenarios, the future level of atmospheric deposition will affect Hg concentrations and sediment recovery times. Though limited by inherent simplifications, this work results show that the reconstruction of historical dynamics using a holistic approach, supported by data, can improve our understanding of the pollutants distribution and the quantification of local emissions. Downscaling from trends predicted at the global scale taking into account for regional differences seems useful to investigate the pollutants fate.
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Affiliation(s)
- Ginevra Rosati
- National Institute of Oceanography and Applied Geophysics - OGS, Trieste, Italy.
| | - Cosimo Solidoro
- National Institute of Oceanography and Applied Geophysics - OGS, Trieste, Italy
| | - Donata Canu
- National Institute of Oceanography and Applied Geophysics - OGS, Trieste, Italy
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29
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Chellman N, Csank A, Gustin MS, Arienzo MM, Vargas Estrada M, McConnell JR. Comparison of co-located ice-core and tree-ring mercury records indicates potential radial translocation of mercury in whitebark pine. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 743:140695. [PMID: 32679494 DOI: 10.1016/j.scitotenv.2020.140695] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 06/05/2020] [Accepted: 06/30/2020] [Indexed: 06/11/2023]
Abstract
Tree-ring records are a potential archive for reconstructing long-term historical trends in atmospheric mercury (Hg) concentrations. Although Hg preserved in tree rings has been shown to be derived largely from the atmosphere, quantitative relationships linking atmospheric concentrations to those in tree rings are limited. In addition, few tree-ring-based Hg records have been evaluated against co-located proxies of atmospheric Hg deposition or direct atmospheric measurements. Here we develop long-term Hg records extending from 1800 to 2018 CE using cores collected from two stands of whitebark pine located near the Upper Fremont Glacier in the Wind River Range, Wyoming, where a long-term record of atmospheric Hg deposition previously was developed from an ice core. The tree ring record showed that Hg concentrations increased beginning in 1800 CE to a broad peak centered at ~1960 CE, before decreasing to present, generally paralleling the ice-core record of Hg deposition. The exact timing and magnitude of the Hg increases in the trees, however, is offset earlier relative to the ice-core record. These discrepancies potentially arise from biotic processes that impact Hg uptake and preservation in whitebark pine, and results from an advection-diffusion model indicate that the temporal differences are consistent with radial movement of Hg within the trees. The forms of atmospheric Hg and seasonality may also impact the Hg record preserved by each archive, but are less likely to affect long-term trends. Further work is needed to assess radial Hg translocation in more controlled studies with larger sample sizes.
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Affiliation(s)
- Nathan Chellman
- Desert Research Institute, Division of Hydrologic Sciences, Reno, NV 89512, United States; Graduate Program of Hydrologic Sciences, University of Nevada, Reno, NV 89557, United States.
| | - Adam Csank
- Department of Geography, University of Nevada, Reno, NV 89557, United States
| | - Mae Sexauer Gustin
- Department of Natural Resources and Environmental Science, University of Nevada, Reno, NV 89557, United States
| | - Monica M Arienzo
- Desert Research Institute, Division of Hydrologic Sciences, Reno, NV 89512, United States
| | - Margarita Vargas Estrada
- Department of Natural Resources and Environmental Science, University of Nevada, Reno, NV 89557, United States
| | - Joseph R McConnell
- Desert Research Institute, Division of Hydrologic Sciences, Reno, NV 89512, United States
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30
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Perkins M, Lane OP, Evers DC, Sauer A, Adams EM, O'Driscoll NJ, Edmunds ST, Jackson AK, Hagelin JC, Trimble J, Sunderland EM. Historical patterns in mercury exposure for North American songbirds. ECOTOXICOLOGY (LONDON, ENGLAND) 2020; 29:1161-1173. [PMID: 31161526 DOI: 10.1007/s10646-019-02054-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/09/2019] [Indexed: 06/09/2023]
Abstract
Methylmercury (MeHg) is a global environmental contaminant that poses significant risks to the health of humans, wildlife, and ecosystems. Assessing MeHg exposure in biota across the landscape and over time is vital for monitoring MeHg pollution and gauging the effectiveness of regulations intended to reduce new mercury (Hg) releases. We used MeHg concentrations measured in museum specimen feathers (collected between 1869 and 2014) and total Hg concentrations (as a proxy for MeHg) of feathers sampled from wild birds (collected between 2008 and 2017) to investigate temporal patterns in exposure over approximately 150 years for North American songbirds. For individual species, we found greater concentrations for samples collected post-2000 compared to those collected during historic times (pre-1900) for six of seven songbird species. Mean feather concentrations measured in samples collected post-2000 ranged between 1.9 and 17 times (mean 6.6) greater than historic specimens. The proportion of individual songbirds with feather concentrations that exceeded modeled toxicity benchmarks increased in samples collected after 1940. Only 2% of individual songbirds collected prior to 1940 had feather concentrations greater than 2.4 μg/g (a toxicity benchmark related to a 10% decrease in nest success) compared to 35% of individuals collected post-1940. Many species included in this study have a vulnerable or near-threatened conservation status, suggesting recovery actions are needed to address mercury pollution.
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Affiliation(s)
- Marie Perkins
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA.
| | - Oksana P Lane
- Biodiversity Research Institute, Portland, ME, 04103, USA
| | - David C Evers
- Biodiversity Research Institute, Portland, ME, 04103, USA
| | - Amy Sauer
- Biodiversity Research Institute, Portland, ME, 04103, USA
| | - Evan M Adams
- Biodiversity Research Institute, Portland, ME, 04103, USA
| | - Nelson J O'Driscoll
- K. C. Irving Environmental Science Centre, Department of Earth and Environmental Sciences, Acadia University, Wolfville, NS, B4P 2R6, Canada
| | | | - Allyson K Jackson
- Department of Environmental Studies, Purchase College, SUNY, Purchase, NY, 10577, USA
| | - Julie C Hagelin
- Alaska Department of Fish and Game, Threatened, Endangered and Diversity Program, Fairbanks, AK, 99701, USA
| | - Jeremiah Trimble
- Museum of Comparative Zoology, Harvard University, Cambridge, MA, 02138, USA
| | - Elsie M Sunderland
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
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31
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Sun R, Yuan J, Sonke JE, Zhang Y, Zhang T, Zheng W, Chen S, Meng M, Chen J, Liu Y, Peng X, Liu C. Methylmercury produced in upper oceans accumulates in deep Mariana Trench fauna. Nat Commun 2020; 11:3389. [PMID: 32636418 PMCID: PMC7341844 DOI: 10.1038/s41467-020-17045-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 06/08/2020] [Indexed: 12/04/2022] Open
Abstract
Monomethylmercury (MMHg) is a potent toxin that bioaccumulates and magnifies in marine food webs. Recent studies show abundant methylated Hg in deep oceans (>1000 m), yet its origin remains uncertain. Here we measured Hg isotope compositions in fauna and surface sediments from the Mariana Trench. The trench fauna at 7000-11000 m depth all have substantially positive mass-independent fractionation of odd Hg isotopes (odd-MIF), which can be generated only in the photic zone via MMHg photo-degradation. Given the identical odd-MIF in trench fauna and North Pacific upper ocean (<1000 m) biota MMHg, we suggest that the accumulated Hg in trench fauna originates exclusively from MMHg produced in upper oceans, which penetrates to depth by sorption to sinking particles. Our findings reveal little in-situ MMHg production in deep oceans and imply that anthropogenic Hg released at the Earth's surface is much more pervasive across deep oceans than was previously thought.
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Affiliation(s)
- Ruoyu Sun
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, 300072, Tianjin, China
| | - Jingjing Yuan
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, 300072, Tianjin, China
| | - Jeroen E Sonke
- Laboratoire Géosciences Environnement Toulouse, CNRS/Institute for Research and Development/Université Paul Sabatier-Toulouse III, 31400, Toulouse, France
| | - Yanxu Zhang
- School of Atmospheric Sciences, Nanjing University, 210023, Jiangsu, 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 Rd., 300350, Tianjin, China
| | - Wang Zheng
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, 300072, Tianjin, China
| | - Shun Chen
- Deep Sea Science Division, Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, 572000, Sanya, Hainan, China
| | - Mei Meng
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, 300072, Tianjin, China
| | - Jiubin Chen
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, 300072, Tianjin, China
| | - Yi Liu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, 300072, Tianjin, China.
| | - Xiaotong Peng
- Deep Sea Science Division, Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, 572000, Sanya, Hainan, China.
| | - Congqiang Liu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, 300072, Tianjin, China
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32
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Bowman KL, Lamborg CH, Agather AM. A global perspective on mercury cycling in the ocean. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 710:136166. [PMID: 32050358 DOI: 10.1016/j.scitotenv.2019.136166] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 12/10/2019] [Accepted: 12/15/2019] [Indexed: 05/20/2023]
Abstract
Mercury (Hg) is a ubiquitous metal in the ocean that undergoes in situ chemical transformations in seawater and marine sediment. Most relevant to public health is the production of monomethyl-Hg, a neurotoxin to humans that accumulates in marine fish and mammals. Here we synthesize 30 years of Hg measurements in the ocean to discuss sources, sinks, and internal cycling of this toxic metal. Global-scale oceanographic survey programs (i.e. CLIVAR and GEOTRACES), refined protocols for clean sampling, and analytical advancements have produced over 200 high-resolution, full-depth profiles of total Hg, methylated Hg, and gaseous elemental Hg throughout the Atlantic, Pacific, Arctic, and Southern Oceans. Vertical maxima of methylated Hg were found in surface waters, near the subsurface chlorophyll maximum, and in low-oxygen thermocline waters. The greatest concentration of Hg in deep water was measured in Antarctic Bottom Water, and in newly formed Labrador Sea Water, Hg showed a decreasing trend over the past 20 years. Distribution of Hg in polar oceans was unique relative to lower latitudes with higher concentrations of total Hg near the surface and vertical trends of Hg speciation driven by water column stratification and seasonal ice cover. Global models of Hg in the ocean require a better understanding of biogeochemical controls on Hg speciation and improved accuracy of methylated Hg measurements within the international community.
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Affiliation(s)
- Katlin L Bowman
- Moss Landing Marine Laboratories, 8272 Moss Landing Road, Moss Landing, CA 95039, USA; University of California Santa Cruz, Ocean Sciences Department, 1156 High Street, Santa Cruz, CA 95064, USA.
| | - Carl H Lamborg
- University of California Santa Cruz, Ocean Sciences Department, 1156 High Street, Santa Cruz, CA 95064, USA.
| | - Alison M Agather
- National Oceanic and Atmospheric Administration, 1325 East West Highway, Silver Spring, MD 20910, USA.
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Cooke CA, Martínez-Cortizas A, Bindler R, Sexauer Gustin M. Environmental archives of atmospheric Hg deposition - A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 709:134800. [PMID: 31887515 DOI: 10.1016/j.scitotenv.2019.134800] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 09/30/2019] [Accepted: 10/02/2019] [Indexed: 06/10/2023]
Abstract
Environmental archives offer an opportunity to reconstruct temporal trends in atmospheric Hg deposition at various timescales. Lake sediment and peat have been the most widely used archives; however, new records from ice, tree rings, and the measurement of Hg stable isotopes, are offering new insights into past Hg cycling. Preindustrial Hg deposition has been studied over decadal to millennial timescales extending as far back as the late Pleistocene. Exploitation of mercury deposits (mainly cinnabar) first began during the mid to late Holocene in South America, Europe, and Asia, but increased dramatically during the Colonial era (1532-1900) for silver production. However, evidence for preindustrial Hg pollution is restricted to regions directly downwind or downstream of cinnabar or precious metal mining centers. Excluding these areas, there has been an approximately four-fold increase in atmospheric deposition globally over the industrial era (i.e., since 1800-1850), though regional differences exist, especially during the early 20th Century. Lake sediments, peat, ice, and tree rings are all influenced by (and integrate) a range of processes. For example, lake sediments are influenced by atmospheric deposition, sediment focusing, and the input of allochthonous material from the watershed, peat records reflect atmospheric deposition and biotic uptake, ice cores are a record of Hg scrubbed during precipitation, and tree rings record atmospheric concentrations. No archive represents an absolute record of past Hg deposition or concentrations, and post-depositional transformation of Hg profiles remains an important topic of research. However, natural archives continue to provide important insight into atmospheric Hg cycling over various timescales.
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Affiliation(s)
- Colin A Cooke
- Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta T6G 2E3, Canada; Environmental Monitoring and Science Division, Alberta Environment and Parks, Government of Alberta, Edmonton, Alberta T5J 5C6 Canada.
| | - Antonio Martínez-Cortizas
- EcoPast (GI-1553), Facultade de Bioloxía, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Richard Bindler
- Department of Ecology and Environmental Science, Umeå University, Umeå, Sweden
| | - Mae Sexauer Gustin
- Department of Natural Resources and Environmental Science, University of Nevada-Reno Reno, Nevada 89557, United States
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Wang C, Wang Z, Zhang X. Characteristics of mercury speciation in seawater and emission flux of gaseous mercury in the Bohai Sea and Yellow Sea. ENVIRONMENTAL RESEARCH 2020; 182:109092. [PMID: 32069770 DOI: 10.1016/j.envres.2019.109092] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 12/25/2019] [Accepted: 12/25/2019] [Indexed: 06/10/2023]
Abstract
Four cruises were performed in the Bohai Sea (BS) and Yellow Sea (YS) to ascertain the levels and distributions of gaseous elemental mercury (GEM), dissolved gaseous mercury (DGM), methylmercury (MeHg), and total mercury (THg) during 2012 and 2014. Their concentrations and Hg0 flux exhibited clear spatial-temporal distributions. The GEM level over the BS in spring (2.71 ± 0.49 ng m-3) was significantly higher than that in fall (1.98 ± 0.91 ng m-3). Air masses with elevated GEM mainly originated from northern China. During the two cruises in 2012 over the BS, the mean DGM concentration in spring (35.7 ± 4.6 pg l-1) was comparable to that in fall (32.4 ± 4.6 pg l-1). During the spring cruise of 2014, the mean DGM concentration in the BS (52.8 ± 12.5 pg l-1) was comparable to that in the YS (52.4 ± 14.1 pg l-1), while during the fall cruise of 2014, it was significantly lower in the BS (26.7 ± 14.4 pg l-1) than in the YS (57.2 ± 17.9 pg l-1). DGM represents a small portion of unfiltered THg in the BS (3.95%) and YS (5.12%). The MeHg and MeHg% values were higher in nearshore areas than in open sea, indicating higher productivity in coastal regions. The Hg0 flux in the YS (4.56 ng m-2 h-1) was about twice that in the BS. The annual emission Hg0 fluxes from the BS and YS were 2.71 and 23.68 tons yr-1, respectively.
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Affiliation(s)
- Chunjie Wang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing, 100085, China
| | - Zhangwei Wang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing, 100085, China
| | - Xiaoshan Zhang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing, 100085, China.
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Global warming accelerates uptake of atmospheric mercury in regions experiencing glacier retreat. Proc Natl Acad Sci U S A 2020; 117:2049-2055. [PMID: 31932430 DOI: 10.1073/pnas.1906930117] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
As global climate continues to warm, melting of glaciers releases a large quantity of mercury (Hg) originally locked in ice into the atmosphere and downstream ecosystems. Here, we show an opposite process that captures atmospheric Hg through glacier-to-vegetation succession. Our study using stable isotope techniques at 3 succession sites on the Tibetan Plateau reveals that evolving vegetation serves as an active "pump" to take up gaseous elemental mercury (Hg0) from the atmosphere. The accelerated uptake enriches the Hg pool size in glacier-retreated areas by a factor of ∼10 compared with the original pool size in the glacier. Through an assessment of Hg source-sink relationship observed in documented glacier-retreated areas in the world (7 sites of tundra/steppe succession and 5 sites of forest succession), we estimate that 400 to 600 Mg of Hg has been accumulated in glacier-retreated areas (5‰ of the global land surface) since the Little Ice Age (∼1850). By 2100, an additional ∼300 Mg of Hg will be sequestered from the atmosphere in glacier-retreated regions globally, which is ∼3 times the total Hg mass loss by meltwater efflux (∼95 Mg) in alpine and subpolar glacier regions. The recapturing of atmospheric Hg by vegetation in glacier-retreated areas is not accounted for in current global Hg models. Similar processes are likely to occur in other regions that experience increased vegetation due to climate or land use changes, which need to be considered in the assessment of global Hg cycling.
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Wang X, Yuan W, Feng X, Wang D, Luo J. Moss facilitating mercury, lead and cadmium enhanced accumulation in organic soils over glacial erratic at Mt. Gongga, China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 254:112974. [PMID: 31376600 DOI: 10.1016/j.envpol.2019.112974] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 07/26/2019] [Accepted: 07/26/2019] [Indexed: 06/10/2023]
Abstract
Moss is usually as an initial colonizer in alpine glacier retreated regions. We hypothesized that moss can significantly facilitate the toxic metals accumulation in alpine ecosystems based on its strong ability of absorption and the role in soil development. Hence, we investigated the trace element pool sizes and enrichment factors, especially for mercury (Hg) by using the Hg isotopic compositions to determine the source contributions in a moss-dominated ecosystem over glacial erratic in Eastern Tibetan Plateau. Results show that Hg, lead (Pb) and cadmium (Cd) are highly enriched in organic soils. Specifically, Cd concentration is 5-20 times higher than the safety limit of the acid soil (pH ≤ 5.5) in China. Atmospheric depositions dominantly contribute to the Pb and Cd sources in organic soils, and followed by the moraine particles influences. The lowering pH in organic soils increasing with glacial retreated time results in the desorption of Cd in organic soils. Atmospheric Hg0 uptake by moss predominantly contributes to the Hg sources in organic soils. The average Pb accumulation rate over last 125-year is about 5.6 ± 1.0 mg m-2 yr-1, and for Cd is 0.4 ± 0.1 mg m-2 yr-1, and for Hg0 is 27.6 ± 3.2 μg m-2 yr-1. These elevated accumulation rates are caused by the high moss biomass and elevated atmospheric Hg, Pb and Cd pollution levels in China and neighbouring regions. Our study indicates that the moss not only as the bioindicator, but also plays an important role in the hazardous metal biogeochemical cycling in alpine regions.
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Affiliation(s)
- Xun Wang
- College of Resources and Environment, Southwest University, Chongqing, 400715, China; State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Wei Yuan
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China.
| | - Dingyong Wang
- College of Resources and Environment, Southwest University, Chongqing, 400715, China
| | - Ji Luo
- Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences & Ministry of Water Conservancy, Chengdu, 610041, China
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37
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Goñi-Urriza M, Klopp C, Ranchou-Peyruse M, Ranchou-Peyruse A, Monperrus M, Khalfaoui-Hassani B, Guyoneaud R. Genome insights of mercury methylation among Desulfovibrio and Pseudodesulfovibrio strains. Res Microbiol 2019; 171:3-12. [PMID: 31655199 DOI: 10.1016/j.resmic.2019.10.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 10/10/2019] [Accepted: 10/11/2019] [Indexed: 01/28/2023]
Abstract
Mercury methylation converts inorganic mercury into the toxic methylmercury, and the consequences of this transformation are worrisome for human health and the environment. This process is performed by anaerobic microorganisms, such as several strains related to Pseudodesulfovibrio and Desulfovibrio genera. In order to provide new insights into the molecular mechanisms of mercury methylation, we performed a comparative genomic analysis on mercury methylators and non-methylators from (Pseudo)Desulfovibrio strains. Our results showed that (Pseudo)Desulfovibrio species are phylogenetically and metabolically distant and consequently, these genera should be divided into various genera. Strains able to perform methylation are affiliated with one branch of the phylogenetic tree, but, except for hgcA and hgcB genes, no other specific genetic markers were found among methylating strains. hgcA and hgcB genes can be found adjacent or separated, but proximity between those genes does not promote higher mercury methylation. In addition, close examination of the non-methylator Pseudodesulfovibrio piezophilus C1TLV30 strain, showed a syntenic structure that suggests a recombination event and may have led to hgcB depletion. The genomic analyses identify also arsR gene coding for a putative regulator upstream hgcA. Both genes are cotranscribed suggesting a role of ArsR in hgcA expression and probably a role in mercury methylation.
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Affiliation(s)
- Marisol Goñi-Urriza
- Environmental Microbiology, CNRS/UNIV PAU & PAYS ADOUR/E2S UPPA, Institut des Sciences Analytiques et de Physicochimie pour l'Environnement et les Matériaux, IPREM, UMR5254, Pau, France.
| | - Christophe Klopp
- Plateforme Bioinformatique Genotoul, UR875 Biométrie et Intelligence Artificielle, INRA, Castanet-Tolosan, France.
| | - Magali Ranchou-Peyruse
- Environmental Microbiology, CNRS/UNIV PAU & PAYS ADOUR/E2S UPPA, Institut des Sciences Analytiques et de Physicochimie pour l'Environnement et les Matériaux, IPREM, UMR5254, Pau, France.
| | - Anthony Ranchou-Peyruse
- Environmental Microbiology, CNRS/UNIV PAU & PAYS ADOUR/E2S UPPA, Institut des Sciences Analytiques et de Physicochimie pour l'Environnement et les Matériaux, IPREM, UMR5254, Pau, France.
| | - Mathilde Monperrus
- CNRS/UNIV PAU & PAYS ADOUR/E2S UPPA, Institut des Sciences Analytiques et de Physicochimie pour l'Environnement et les Matériaux, IPREM, UMR5254, Anglet, France.
| | - Bahia Khalfaoui-Hassani
- Environmental Microbiology, CNRS/UNIV PAU & PAYS ADOUR/E2S UPPA, Institut des Sciences Analytiques et de Physicochimie pour l'Environnement et les Matériaux, IPREM, UMR5254, Pau, France.
| | - Rémy Guyoneaud
- Environmental Microbiology, CNRS/UNIV PAU & PAYS ADOUR/E2S UPPA, Institut des Sciences Analytiques et de Physicochimie pour l'Environnement et les Matériaux, IPREM, UMR5254, Pau, France.
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38
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Schudel G, Kaplan R, Adler Miserendino R, Veiga MM, Velasquez-López PC, Guimarães JRD, Bergquist BA. Mercury isotopic signatures of tailings from artisanal and small-scale gold mining (ASGM) in southwestern Ecuador. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 686:301-310. [PMID: 31181517 DOI: 10.1016/j.scitotenv.2019.06.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 06/01/2019] [Accepted: 06/01/2019] [Indexed: 06/09/2023]
Abstract
Artisanal and small-scale gold mining (ASGM) is currently one of the largest anthropogenic sources of mercury (Hg) to the atmosphere and a significant source to downstream terrestrial aquatic systems. Given the potential toxicity of Hg when it is released to aquatic ecosystems, both scientific and regulatory communities have interest in the development of tools and methods for understanding the fate and transport of Hg in the environment. Although Hg isotopes are applied extensively to trace other anthropogenic point sources of Hg in aquatic ecosystems, few studies have used isotopic analyses to investigate the downstream impacts of ASGM. Furthermore, these studies are currently limited by relatively sparse Hg isotopic analyses on ASGM materials. In this study, ASGM samples from Portovelo-Zaruma (Ecuador), representing various stages of the processing of low-grade gold-bearing ores, were analyzed for Hg concentrations and stable isotope ratios. These data were used to assess the isotopic variability of the ASGM endmember and confirm the results of prior isotopic analyses of ASGM materials and downstream sediments from Portovelo-Zaruma. While the Hg concentrations of the ASGM samples varied significantly, isotopic analyses revealed a limited range of signatures that was characterized by relatively heavy mass-dependent fractionation (MDF) with little to no significant mass-independent fractionation (MIF). The signatures of ASGM samples analyzed in this study matched well with previously reported ASGM samples from Portovelo-Zaruma as well as downstream sediments (for up to 120 km). Furthermore, the overall Hg isotopic compositions of potential ASGM endmembers are distinct from typical compositions observed in freshwater ecosystems (e.g., from soil erosion, atmospheric deposition), allowing Hg isotopes to be a powerful tool in tracing downstream Hg contamination from ASGM.
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Affiliation(s)
- Gary Schudel
- University of Toronto, Department of Earth Sciences, 22 Russell Street, Toronto M5S 3B1, ON, Canada
| | - Robert Kaplan
- University of Toronto, Department of Earth Sciences, 22 Russell Street, Toronto M5S 3B1, ON, Canada
| | - Rebecca Adler Miserendino
- University of Toronto, Department of Earth Sciences, 22 Russell Street, Toronto M5S 3B1, ON, Canada; Johns Hopkins University Bloomberg School of Public Health, Department of Environmental Health Sciences, 615 N. Wolfe Street, Baltimore 21205-2103, MD, USA
| | - Marcello M Veiga
- University of British Columbia, Norman B. Keevil Institute of Mining Engineering, Vancouver, BC V6T IZ4, Canada
| | - P Colon Velasquez-López
- Universidad Tecnica de Machala, Avenida Paquisha Km 5,5 via Pasaje-Machala, Machala, El Oro, Ecuador
| | - Jean Remy Davée Guimarães
- Universidade Federal do Rio de Janeiro, Inst. de Biofísica Carlos Chagas Filho, Bloco G, CCS, Ilha do Fundão, Rio de Janeiro 21949-902, Brazil
| | - Bridget A Bergquist
- University of Toronto, Department of Earth Sciences, 22 Russell Street, Toronto M5S 3B1, ON, Canada.
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39
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Wang X, Yuan W, Lin CJ, Zhang L, Zhang H, Feng X. Climate and Vegetation As Primary Drivers for Global Mercury Storage in Surface Soil. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:10665-10675. [PMID: 31434480 DOI: 10.1021/acs.est.9b02386] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Soil is the largest Hg reservoir globally. Data of Hg concentration in surface soil are fundamental to understanding environmental Hg cycling. However, present knowledge on the quantity and global distribution of Hg in soil remains deficient. Using stable Hg isotopic analyses and geospatial data, the concentration and global spatial distribution of Hg in surface soil of 0-20 cm depth have been developed. It is estimated that 1088 ± 379 Gg of Hg is stored in surface soil globally. Thirty-two percent of the surface Hg storage resides in tropical/subtropical forest regions, 23% in temperate/boreal forest regions, 28% in grassland and steppe and shrubland, 7% in tundra, and 10% in desert and xeric shrubland. Evidence from Hg isotopic signatures points to atmospheric Hg0 dry deposition through vegetation uptake as the primary source of Hg in surface soil. Given the influence of changing climate on vegetative development, global climate change can act as an important forcing factor for shaping spatial distribution of Hg in surface soil. This active forcing cycle significantly dilutes the impacts caused by Hg release from anthropogenic sources, and needs to be considered in assessing the effectiveness of reducing Hg use and emissions as specified in Minamata Convention on Mercury.
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Affiliation(s)
- Xun Wang
- State Key Laboratory of Environmental Geochemistry , Institute of Geochemistry, Chinese Academy of Sciences , Guiyang 550081 , China
| | - Wei Yuan
- State Key Laboratory of Environmental Geochemistry , Institute of Geochemistry, Chinese Academy of Sciences , Guiyang 550081 , China
- University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Che-Jen Lin
- Center for Advances in Water and Air Quality , Lamar University , Beaumont , Texas 77705 , United States
- Department of Civil and Environmental Engineering , Lamar University , Beaumont , Texas 77705 , United States
| | - Leiming Zhang
- Air Quality Research Division, Science and Technology Branch , Environment and Climate Change Canada , Toronto , Ontario M3H 5T4 , Canada
| | - Hui Zhang
- State Key Laboratory of Environmental Geochemistry , Institute of Geochemistry, Chinese Academy of Sciences , Guiyang 550081 , China
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry , Institute of Geochemistry, Chinese Academy of Sciences , Guiyang 550081 , China
- Center for Excellence in Quaternary Science and Global Change , Chinese Academy of Sciences , Xian 710061 , China
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40
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Roberts S, Kirk JL, Wiklund JA, Muir DCG, Yang F, Gleason A, Lawson G. Mercury and metal(loid) deposition to remote Nova Scotia lakes from both local and distant sources. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 675:192-202. [PMID: 31030127 DOI: 10.1016/j.scitotenv.2019.04.167] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 04/08/2019] [Accepted: 04/11/2019] [Indexed: 06/09/2023]
Abstract
Kejimkujik National Park, in Nova Scotia, Canada, is a sensitive region for metal(loid) contamination, such as mercury, in part due to long-range atmospheric deposition from global and regional industrial centers. The region is remote from industrial centres, but is downwind of major pollution sources in the Eastern United States and Canada, and historically had numerous gold mining sites. Due to a paucity of long-term atmospheric deposition monitoring in this region, little is known about the response of Kejimkujik lakes to multiple changing global, regional and local atmospheric Hg and metal(loid) sources. Here, we used multiple lake sediment cores to reconstruct anthropogenic depositional fluxes of metal(loid)s of concern for the last ~210years. Results showed that Kejimkujik lake sediments are highly enriched in lead (Pb), antimony (Sb) and tin (Sn), with post-industrial metal(loid) concentrations being >4-fold greater than natural baseline levels (prior to ~1800) and moderately enriched in silver (Ag), bismuth (Bi), cadmium (Cd), copper (Cu), mercury (Hg), rubidium (Rb), tellurium (Te), thallium (Tl), vanadium (V), tungsten (W) and zinc (Zn), with post-industrial metal(loid) concentrations being between 1.5 and 4-fold greater than natural baseline levels (prior to ~1800). Lake sediment core reconstructions of total atmospheric Hg deposition matched well with Hg wet deposition monitoring data from the overlapped period (1997-2010) being 9.1±2.7μg/m2/yr and 7.0±0.7μg/m2/yr respectively. Lakes closest to historic gold mining sites show spikes in Ag, Cd, Sb, Tl, Zn and W during mining periods (~1880 and 1950). Most of the enriched metal(loid)s (EF >1.5) (Ag, Bi, Cu, Hg, Pb, Sb, Sn, V and W) do not appear affected by redox and remobilisation issues. For the other enriched metal(loid)s (EF >1.5) (Cd, Tl, and Zn), remobilisation from upper sediments appears to be occurring within these acidic and DOC rich Kejimkujik lakes.
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Affiliation(s)
- S Roberts
- Aquatic Contaminants Research Division, Environment and Climate Change Canada, Burlington, Ontario L7R 4A6, Canada.
| | - J L Kirk
- Aquatic Contaminants Research Division, Environment and Climate Change Canada, Burlington, Ontario L7R 4A6, Canada.
| | - J A Wiklund
- Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - D C G Muir
- Aquatic Contaminants Research Division, Environment and Climate Change Canada, Burlington, Ontario L7R 4A6, Canada
| | - F Yang
- Aquatic Contaminants Research Division, Environment and Climate Change Canada, Burlington, Ontario L7R 4A6, Canada
| | - A Gleason
- Aquatic Contaminants Research Division, Environment and Climate Change Canada, Burlington, Ontario L7R 4A6, Canada
| | - G Lawson
- Aquatic Contaminants Research Division, Environment and Climate Change Canada, Burlington, Ontario L7R 4A6, Canada
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41
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Kurz AY, Blum JD, Washburn SJ, Baskaran M. Changes in the mercury isotopic composition of sediments from a remote alpine lake in Wyoming, USA. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 669:973-982. [PMID: 30970464 DOI: 10.1016/j.scitotenv.2019.03.165] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 03/11/2019] [Accepted: 03/12/2019] [Indexed: 06/09/2023]
Abstract
Mercury (Hg) deposition from the atmosphere has increased dramatically since 1850 and Hg isotope records in lake sediments can be used to identify changes in the sources and cycling of Hg. We collected a sediment core from a remote lake (Lost Lake, Wyoming, USA) and measured vertical variation of Hg concentration and isotopic composition as well as 210Pb and 137Cs activities to establish a chronology. We also analyzed vegetation and soil samples from the watershed which has a small ratio of watershed area to lake surface area (2.06). The Hg flux remains constant from ~1350 to 1850 before increasing steadily to modern values that are approximately four times pre-1850 values. The modern Hg isotopic composition preserved in the sediments is distinct from the Hg isotopic composition of pre-1850 samples with both δ202Hg and Δ199Hg becoming progressively more positive through time, with shifts of +0.37‰ and +0.23‰ respectively. To explain temporal changes in δ202Hg, Δ199Hg, and Hg concentration in the core segments, we estimated a present-day atmospheric endmember based on precipitation and snow samples collected near Lost Lake. The observed change in Hg isotopic values through time cannot be explained solely by addition of anthropogenic Hg with the isotopic composition that has been estimated by others for global anthropogenic emissions. Instead, the isotope variation suggests that the relative importance of redox transformations, whether in the atmosphere, within the lake, or both, have changed since 1850.
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Affiliation(s)
- Aaron Y Kurz
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI 48109, United States.
| | - Joel D Blum
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI 48109, United States
| | - Spencer J Washburn
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI 48109, United States
| | - Mark Baskaran
- Department of Geology, Wayne State University, Detroit, MI 48201, United States
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42
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Mason RP, Baumann Z, Hansen G, Yao KM, Coulibaly M, Coulibaly S. An assessment of the impact of artisanal and commercial gold mining on mercury and methylmercury levels in the environment and fish in Cote d'Ivoire. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 665:1158-1167. [PMID: 30893747 DOI: 10.1016/j.scitotenv.2019.01.393] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 01/28/2019] [Accepted: 01/29/2019] [Indexed: 06/09/2023]
Abstract
Artisanal and small-scale gold mining (ASGM) activities are an important source of mercury (Hg) to the atmosphere globally, and in most countries in West Africa, where gold production has increased dramatically in the last decade from both commercial and ASGM activities. This study focused on examining the concentrations of Hg and methylmercury (MeHg) in water, sediments and fish in four regions associated with gold mining activities in Cote d'Ivoire to assess the potential exposure of the local communities to MeHg from fish consumption. Concentrations of dissolved total Hg and MeHg in water and sediment were elevated at some locations sample and were indicative of local contamination. Several locations had sediment total Hg above 100 ng g-1 and sediment %MeHg ranged from 0.03 to 4.4%. Fish concentrations exceeded 0.3 μg/ g wet wt., especially for carnivores and fish caught in the western region of the country. Bioaccumulation factors, relative to dissolved MeHg, were higher for carnivores than omnivores and varied with region, suggesting other factors besides MeHg concentration alone were impacting uptake and trophic transfer. Given that people in Cote d'Ivoire consume fish at a higher level than other countries, the levels in fish were sufficient to exceed the US EPA's guidance criteria even at average consumption levels, and particularly for people consuming fish at a higher rate. Overall, this study provides compelling evidence that ASGM activities in Cote d'Ivoire are leading to elevated exposure and likely impacting the health of the local populations in regions where such activity is occurring.
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Affiliation(s)
- Robert P Mason
- Dept. Marine Sciences, University of Connecticut, Groton, CT, USA.
| | - Zofia Baumann
- Dept. Marine Sciences, University of Connecticut, Groton, CT, USA
| | - Gunnar Hansen
- Dept. Marine Sciences, University of Connecticut, Groton, CT, USA
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Guédron S, Tolu J, Brisset E, Sabatier P, Perrot V, Bouchet S, Develle AL, Bindler R, Cossa D, Fritz SC, Baker PA. Late Holocene volcanic and anthropogenic mercury deposition in the western Central Andes (Lake Chungará, Chile). THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 662:903-914. [PMID: 30708305 DOI: 10.1016/j.scitotenv.2019.01.294] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 01/22/2019] [Accepted: 01/22/2019] [Indexed: 06/09/2023]
Abstract
Volcanism is one of the major natural processes emitting mercury (Hg) to the atmosphere, representing a significant component of the global Hg budget. The importance of volcanic eruptions for local-scale Hg deposition was investigated using analyses of Hg, inorganic elemental tracers, and organic biomarkers in a sediment sequence from Lake Chungará (4520 m a.s.l.). Environmental change and Hg deposition in the immediate vicinity of the Parinacota volcano were reconstructed over the last 2700 years, encompassing the pre-anthropogenic and anthropogenic periods. Twenty eruptions delivering large amounts of Hg (1 to 457 μg Hg m-2 yr-1 deposited at the timescale of the event) were locally recorded. Peaks of Hg concentration recorded after most of the eruptions were attributed to a decrease in sedimentation rate together with the rapid re-oxidation of gaseous elemental Hg and deposition with fine particles and incorporation into lake primary producers. Over the study period, the contribution of volcanic emissions has been estimated as 32% of the total Hg input to the lake. Sharp depletions in primary production occurred at each eruption, likely resulting from massive volcaniclastic inputs and changes in the lake-water physico-chemistry. Excluding the volcanic deposition periods, Hg accumulation rates rose from natural background values (1.9 ± 0.5 μg m-2 yr-1) by a factor of 2.3 during the pre-colonial mining period (1400-900 yr cal. BP), and by a factor of 6 and 7.6, respectively, during the Hispanic colonial epoch (400-150 yr cal. BP) and the industrial era (~140 yr cal. BP to present). Altogether, the dataset indicates that lake primary production has been the main, but not limiting, carrier for Hg to the sediment. Volcanic activity and climate change are only secondary drivers of local Hg deposition relative to the magnitude of regional and global anthropogenic emissions.
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Affiliation(s)
- S Guédron
- Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, IRD, IFSTTAR, ISTerre, 38000 Grenoble, France; Laboratorio de Hidroquímica, Instituto de Investigaciones Químicas, Universidad Mayor de San Andres, Campus Universitario de Cota Cota, casilla 3161, La Paz, Bolivia.
| | - J Tolu
- Department of Ecology and Environmental Science, Umeå University, Sweden; Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Dübendorf, Switzerland and ETH Zürich, Universitätstrasse 16, CH-8092 Zürich, Switzerland
| | - E Brisset
- Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, IRD, IFSTTAR, ISTerre, 38000 Grenoble, France; IPHES, Institut Català de Paleoecologia Humana i Evolució Social, Tarragona, Spain; Àrea de Prehistòria, Universitat Rovira i Virgili, Tarragona, Spain
| | - P Sabatier
- Environnement, Dynamique et Territoires de Montagne (EDYTEM), Université Savoie Mont Blanc, CNRS, 73373 Le Bourget du Lac, France
| | - V Perrot
- Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, IRD, IFSTTAR, ISTerre, 38000 Grenoble, France
| | - S Bouchet
- LCABIE - Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, IPREM UMR 5254, CNRS et Université de Pau et des Pays de l'Adour, Hélioparc, F-64053 Pau, France; Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Dübendorf, Switzerland and ETH Zürich, Universitätstrasse 16, CH-8092 Zürich, Switzerland
| | - A L Develle
- Environnement, Dynamique et Territoires de Montagne (EDYTEM), Université Savoie Mont Blanc, CNRS, 73373 Le Bourget du Lac, France
| | - R Bindler
- Department of Ecology and Environmental Science, Umeå University, Sweden
| | - D Cossa
- Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, IRD, IFSTTAR, ISTerre, 38000 Grenoble, France
| | - S C Fritz
- Department of Earth and Atmospheric Sciences, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - P A Baker
- Division of Earth and Ocean Sciences, Duke University, Durham, NC, USA
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Corella JP, Saiz-Lopez A, Sierra MJ, Mata MP, Millán R, Morellón M, Cuevas CA, Moreno A, Valero-Garcés BL. Trace metal enrichment during the Industrial Period recorded across an altitudinal transect in the Southern Central Pyrenees. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 645:761-772. [PMID: 30031334 DOI: 10.1016/j.scitotenv.2018.07.160] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 07/03/2018] [Accepted: 07/12/2018] [Indexed: 06/08/2023]
Affiliation(s)
- J P Corella
- Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Rocasolano, CSIC, Serrano 119, 28006 Madrid, Spain.
| | - A Saiz-Lopez
- Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Rocasolano, CSIC, Serrano 119, 28006 Madrid, Spain
| | - M J Sierra
- CIEMAT, Department of the Environment (DMA), Avenida Complutense 40, E-28040 Madrid, Spain
| | - M P Mata
- Instituto Geológico y Minero de España, Rios Rosas 23, 28003 Madrid, Spain
| | - R Millán
- CIEMAT, Department of the Environment (DMA), Avenida Complutense 40, E-28040 Madrid, Spain
| | - M Morellón
- CITIMAC, University of Cantabria, Faculty of Science, Avenida de los Castros s/n, 39005 Santander, Spain
| | - C A Cuevas
- Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Rocasolano, CSIC, Serrano 119, 28006 Madrid, Spain
| | - A Moreno
- Pyrenean Institute of Ecology, CSIC, Avda Montañana 1005, 50059 Zaragoza, Spain; Laboratorio Internacional de Cambio Global, CSIC-PUC-UFRJ, Avda Montañana 1005, 50059 Zaragoza, Spain
| | - B L Valero-Garcés
- Pyrenean Institute of Ecology, CSIC, Avda Montañana 1005, 50059 Zaragoza, Spain; Laboratorio Internacional de Cambio Global, CSIC-PUC-UFRJ, Avda Montañana 1005, 50059 Zaragoza, Spain
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45
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Eurasian river spring flood observations support net Arctic Ocean mercury export to the atmosphere and Atlantic Ocean. Proc Natl Acad Sci U S A 2018; 115:E11586-E11594. [PMID: 30478039 DOI: 10.1073/pnas.1811957115] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Midlatitude anthropogenic mercury (Hg) emissions and discharge reach the Arctic Ocean (AO) by atmospheric and oceanic transport. Recent studies suggest that Arctic river Hg inputs have been a potentially overlooked source of Hg to the AO. Observations on Hg in Eurasian rivers, which represent 80% of freshwater inputs to the AO, are quasi-inexistent, however, putting firm understanding of the Arctic Hg cycle on hold. Here, we present comprehensive seasonal observations on dissolved Hg (DHg) and particulate Hg (PHg) concentrations and fluxes for two large Eurasian rivers, the Yenisei and the Severnaya Dvina. We find large DHg and PHg fluxes during the spring flood, followed by a second pulse during the fall flood. We observe well-defined water vs. Hg runoff relationships for Eurasian and North American Hg fluxes to the AO and for Canadian Hg fluxes into the larger Hudson Bay area. Extrapolation to pan-Arctic rivers and watersheds gives a total Hg river flux to the AO of 44 ± 4 Mg per year (1σ), in agreement with the recent model-based estimates of 16 to 46 Mg per year and Hg/dissolved organic carbon (DOC) observation-based estimate of 50 Mg per year. The river Hg budget, together with recent observations on tundra Hg uptake and AO Hg dynamics, provide a consistent view of the Arctic Hg cycle in which continental ecosystems traffic anthropogenic Hg emissions to the AO via rivers, and the AO exports Hg to the atmosphere, to the Atlantic Ocean, and to AO marine sediments.
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Angot H, Hoffman N, Giang A, Thackray CP, Hendricks AN, Urban NR, Selin NE. Global and Local Impacts of Delayed Mercury Mitigation Efforts. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:12968-12977. [PMID: 30376303 PMCID: PMC6377800 DOI: 10.1021/acs.est.8b04542] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Mercury (Hg) is emitted to air by natural and anthropogenic sources, transports and deposits globally, and bioaccumulates to toxic levels in food webs. It is addressed under the global 2017 Minamata Convention, for which periodic effectiveness evaluation is required. Previous analyses have estimated the impact of different regulatory strategies for future mercury deposition. However, analyses using atmospheric models traditionally hold legacy emissions (recycling of previously deposited Hg) constant, and do not account for their possible future growth. Here, using an integrated modeling approach, we investigate how delays in implementing emissions reductions and the associated growing legacy reservoir affect deposition fluxes to ecosystems in different global regions. Assuming nearly constant yearly emissions relative to 2010, each 5-year delay in peak emissions defers by additional extra ca. 4 years the return to year 2010 global deposition. On a global average, each 5-year delay leads to a 14% decrease in policy impacts on local-scale Hg deposition. We also investigate the response of fish contamination in remote lakes to delayed action. We quantify the consequences of delay for limiting the Hg burden of future generations and show that traditional analyses of policy impacts provide best-case estimates.
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Affiliation(s)
- Hélène Angot
- Institute for Data, Systems, and Society , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Nicholas Hoffman
- Department of Earth, Atmospheric, and Planetary Sciences , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Amanda Giang
- Institute for Data, Systems, and Society , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
- Institute for Resources, Environment and Sustainability , University of British Columbia , Vancouver , British Columbia Canada V6T 1Z4
| | - Colin P Thackray
- Harvard John A. Paulson School of Engineering and Applied Sciences , Harvard University , Cambridge , Massachusetts 02138 , United States
| | - Ashley N Hendricks
- Civil and Environmental Engineering Department , Michigan Technological University , Houghton , Michigan 49931 , United States
| | - Noel R Urban
- Civil and Environmental Engineering Department , Michigan Technological University , Houghton , Michigan 49931 , United States
| | - 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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Liu M, Chen L, He Y, Baumann Z, Mason RP, Shen H, Yu C, Zhang W, Zhang Q, Wang X. Impacts of farmed fish consumption and food trade on methylmercury exposure in China. ENVIRONMENT INTERNATIONAL 2018; 120:333-344. [PMID: 30114623 PMCID: PMC6174094 DOI: 10.1016/j.envint.2018.08.017] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 08/02/2018] [Accepted: 08/02/2018] [Indexed: 05/04/2023]
Abstract
The global pollutant mercury (Hg), especially as methylmercury (MeHg), threatens human and ecosystem health. But major contributors of MeHg exposure to people in China remain highly debated. We developed the China Mercury Exposure Assessment (CMEA) model, which incorporates human exposure pathways for MeHg and total Hg (THg), the interregional, including international and interprovincial, food trading as well as human physiology to provide a comprehensive system that can evaluate the pathway of Hg forms to human consumers in China. Based on the CMEA model that employed the most comprehensive and recent data, we have found that the Probable Daily Intake (PDI) of MeHg for the Chinese population was 0.057 (range: 0.036-0.091 as 60% confidence interval) μg·kg-1·day-1, while that of THg was 0.35 (range: 0.22-0.55) μg·kg-1·day-1. MeHg exposure was dominated by fish intake, especially by farm-raised freshwater fish due to higher consumption of these fish. In 2011, fish intake contributed to 56% to the total MeHg exposure, followed by rice (26%). Consumption of farm-raised fish reduced human exposure to MeHg by 33%. On the other hand, interregional food trading increased MeHg exposure of the Chinese population, as a whole, by 7.6%. The international and interprovincial food trades contributed to 5.1% and 22% of MeHg intake, respectively. For the whole China, fish intake related exposure to MeHg was highest for the Eastern and Northeastern populations, while Tibetans were chronically exposed to the highest MeHg from other sources. Our findings highlight the importance of farmed fish and food trade for MeHg exposure.
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Affiliation(s)
- Maodian Liu
- Ministry of Education Laboratory of Earth Surface Process, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China; Department of Marine Sciences, University of Connecticut, 1080 Shennecossett Road, Groton, CT 06340, USA
| | - Long Chen
- Key Laboratory of Geographic Information Science, Ministry of Education, East China Normal University, Shanghai 200241, China; School of Geographic Sciences, East China Normal University, Shanghai 200241, China
| | - Yipeng He
- Ministry of Education Laboratory of Earth Surface Process, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China; Department of Marine Sciences, University of Connecticut, 1080 Shennecossett Road, Groton, CT 06340, USA
| | - Zofia Baumann
- Department of Marine Sciences, University of Connecticut, 1080 Shennecossett Road, Groton, CT 06340, USA
| | - Robert P Mason
- Department of Marine Sciences, University of Connecticut, 1080 Shennecossett Road, Groton, CT 06340, USA
| | - Huizhong Shen
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Chenghao Yu
- Ministry of Education Laboratory of Earth Surface Process, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Wei Zhang
- School of Environment and Natural Resources, Renmin University of China, Beijing 100872, China
| | - Qianggong Zhang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, China
| | - Xuejun Wang
- Ministry of Education Laboratory of Earth Surface Process, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
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48
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Zhu W, Li Z, Li P, Yu B, Lin CJ, Sommar J, Feng X. Re-emission of legacy mercury from soil adjacent to closed point sources of Hg emission. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 242:718-727. [PMID: 30029171 DOI: 10.1016/j.envpol.2018.07.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 07/01/2018] [Accepted: 07/01/2018] [Indexed: 06/08/2023]
Abstract
Mercury (Hg) emissions from point sources to air may disperse over long distance depending on Hg speciation in the plume. A significant fraction of Hg, particularly in its divalent forms, deposits locally and causes pollution to surrounding biomes. The objective of this study was to investigate (1) the historic Hg deposition to the immediate vicinity of an industrial complex that had intentional use of Hg (i.e., chlor-alkali and polyvinyl chloride production) for 5 decades until 2011, and (2) the Hg0 re-emission from soil to air soon after the closure of the facility. The spatial distribution of near-ground Hg0 vapor in air, soil Hg concentration and stable isotope ratio, air-soil Hg0 flux and Hg0 concentration in soil pore-gas were measured. It was found that the surrounding soils are severely contaminated with Hg due to the Hg release of the industrial complex, displaying soil Hg content up to 4.8 μg g-1. A spatial trend of Hg mass dependent isotope fractionation signature (δ202Hg = -2.11‰ to 0.72‰) with respect to the distance from the closed facility was identified, representing a mixing between regional background and industrial Hg sources. Hg release from the industrial operation enhanced surface soil Hg content within a 6.5-km radius from the facility. Inside the facility, residual Hg wastes (i.e., electrolysis sludge and consumed HgCl2 catalyst) represent a strong localized emission source of atmospheric Hg0. Near-ground atmospheric Hg0 concentration and soil Hg0 efflux progressively elevated toward the facility with an increase by 2-3 orders of magnitude compared to the values observed in the off-site background. These results suggest that the natural soil surfaces surrounding the closed industrial facility act as a large nonpoint source emitting legacy deposited Hg as much as the release from naturally enriched mines.
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Affiliation(s)
- Wei Zhu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
| | - Zhonggen Li
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Ping Li
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Ben Yu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Che-Jen Lin
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; Center for Advances in Water and Air Quality, Lamar University, Beaumont, TX 77710, United States; Department of Civil and Environmental Engineering, Lamar University, Beaumont, TX 77710, United States
| | - Jonas Sommar
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
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49
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Outridge PM, Mason RP, Wang F, Guerrero S, Heimbürger-Boavida LE. Updated Global and Oceanic Mercury Budgets for the United Nations Global Mercury Assessment 2018. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:11466-11477. [PMID: 30226054 DOI: 10.1021/acs.est.8b01246] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In support of international efforts to reduce mercury (Hg) exposure in humans and wildlife, this paper reviews the literature concerning global Hg emissions, cycling and fate, and presents revised global and oceanic Hg budgets for the 2018 United Nations Global Mercury Assessment. We assessed two competing scenarios about the impacts of 16th - late 19th century New World silver (Ag) mining, which may be the largest human source of atmospheric Hg in history. Consideration of Ag ore geochemistry, historical documents on Hg use, and comparison of the scenarios against atmospheric Hg patterns in environmental archives, strongly support a "low mining emission" scenario. Building upon this scenario and other published work, the revised global budget estimates human activities including recycled legacy emissions have increased current atmospheric Hg concentrations by about 450% above natural levels (prevailing before 1450 AD). Current anthropogenic emissions to air are 2.5 ± 0.5 kt/y. The increase in atmospheric Hg concentrations has driven a ∼ 300% average increase in deposition, and a 230% increase in surface marine waters. Deeper marine waters show increases of only 12-25%. The overall increase in Hg in surface organic soils (∼15%) is small due to the large mass of natural Hg already present from rock weathering, but this figure varies regionally. Specific research recommendations are made to reduce uncertainties, particularly through improved understanding of fundamental processes of the Hg cycle, and continued improvements in emissions inventories from large natural and anthropogenic sources.
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Affiliation(s)
- P M Outridge
- Geological Survey of Canada , Natural Resources Canada , 601 Booth St. , Ottawa , Ontario K1A 0E8 , Canada
- Center for Earth Observation Science and Department of Environment and Geography , University of Manitoba , Winnipeg , Manitoba R3T 2N2 , Canada
| | - R P Mason
- Department of Marine Sciences , University of Connecticut , 1080 Shennecossett Road , Groton , Connecticut 06340 , United States
| | - F Wang
- Center for Earth Observation Science and Department of Environment and Geography , University of Manitoba , Winnipeg , Manitoba R3T 2N2 , Canada
| | - S Guerrero
- Universidad Metropolitana, Autopista Caracas Guarenas , Caracas 1073 , Venezuela
| | - L E Heimbürger-Boavida
- Aix Marseille Université , CNRS/INSU, Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, 13288 , Marseille , France
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50
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Zhu S, Zhang Z, Žagar D. Mercury transport and fate models in aquatic systems: A review and synthesis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 639:538-549. [PMID: 29800847 DOI: 10.1016/j.scitotenv.2018.04.397] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 04/29/2018] [Accepted: 04/29/2018] [Indexed: 06/08/2023]
Abstract
Mercury contamination in aquatic systems has been an issue to the natural ecosystem and human health. Environmental models have become a valuable decision-making tool and play a significant role in mercury pollution control and management. This paper gives an overview of currently available models for simulating mercury transport and fate in aquatic systems. The mercury transformation mechanisms included in these models were identified, as well as data limitations in the models' application. Future advances in understanding mercury transport, cycling, and biogeochemistry in both water column and sediment will improve the robustness of current modeling applications. Moreover, additional field data are critically needed to better predict the concentrations of multi-phase mercury species in various aquatic systems, including measurements in the water column, benthic sediments, and organisms. Field data are also crucial for model calibration and validation. Without this information it will not be possible to adequately understand the environmental factors controlling mercury fate in aquatic systems. The insufficient quantity of adequate measurements and the unsatisfactory accuracy of mercury models are, in numerous cases, supplemented by mass balances since they diminish the unreliability of models. Mercury science evolves gradually with the advancement of science and technology, which requires that mathematical modeling of mercury transport and transformation should be consistently updated.
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Affiliation(s)
- Senlin Zhu
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Nanjing Hydraulic Research Institute, Nanjing 210029, China
| | - Zhonglong Zhang
- LimnoTech, Environmental Laboratory, Engineer Research and Development Center, Davis, CA 95616, USA.
| | - Dušan Žagar
- Faculty of Civil and Geodetic Engineering, University of Ljubljana, Jamova 2, 1000 Ljubljana, Slovenia
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