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Gustin MS, Dunham-Cheatham SM, Lyman S, Horvat M, Gay DA, Gačnik J, Gratz L, Kempkes G, Khalizov A, Lin CJ, Lindberg SE, Lown L, Martin L, Mason RP, MacSween K, Vijayakumaran Nair S, Nguyen LSP, O'Neil T, Sommar J, Weiss-Penzias P, Zhang L, Živković I. Measurement of Atmospheric Mercury: Current Limitations and Suggestions for Paths Forward. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:12853-12864. [PMID: 38982755 DOI: 10.1021/acs.est.4c06011] [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: 07/11/2024]
Abstract
Mercury (Hg) researchers have made progress in understanding atmospheric Hg, especially with respect to oxidized Hg (HgII) that can represent 2 to 20% of Hg in the atmosphere. Knowledge developed over the past ∼10 years has pointed to existing challenges with current methods for measuring atmospheric Hg concentrations and the chemical composition of HgII compounds. Because of these challenges, atmospheric Hg experts met to discuss limitations of current methods and paths to overcome them considering ongoing research. Major conclusions included that current methods to measure gaseous oxidized and particulate-bound Hg have limitations, and new methods need to be developed to make these measurements more accurate. Developing analytical methods for measurement of HgII chemistry is challenging. While the ultimate goal is the development of ultrasensitive methods for online detection of HgII directly from ambient air, in the meantime, new surfaces are needed on which HgII can be quantitatively collected and from which it can be reversibly desorbed to determine HgII chemistry. Discussion and identification of current limitations, described here, provide a basis for paths forward. Since the atmosphere is the means by which Hg is globally distributed, accurately calibrated measurements are critical to understanding the Hg biogeochemical cycle.
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Affiliation(s)
- Mae Sexauer Gustin
- College of Biotechnology, Natural Resources & Environmental Science, University of Nevada, Reno, Nevada 89557, United States
| | - Sarrah M Dunham-Cheatham
- College of Biotechnology, Natural Resources & Environmental Science, University of Nevada, Reno, Nevada 89557, United States
| | - Seth 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
| | - Milena Horvat
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana SI-1000, Slovenia
- Jožef Stefan International Postgraduate School, Jožef Stefan Institute, Ljubljana SI-1000, Slovenia
| | - David A Gay
- Wisconsin State Laboratory of Hygiene, University of Wisconsin Madison, Madison, Wisconsin 53707-7996, United States
| | - Jan Gačnik
- College of Biotechnology, Natural Resources & Environmental Science, University of Nevada, Reno, Nevada 89557, United States
| | - Lynne Gratz
- Chemistry Department and Environmental Studies Program, Reed College, Portland, Oregon 97202, United States
| | | | - Alexei Khalizov
- New Jersey Institute of Technology, Newark, New Jersey 07102, United States
| | - Che-Jen Lin
- Lamar University, Beaumont, Texas 77710, United States
| | - Steven E Lindberg
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Livia Lown
- College of Biotechnology, Natural Resources & Environmental Science, University of Nevada, Reno, Nevada 89557, United States
| | - Lynwill Martin
- South Africa Weather Service, Cape Town 7525, South Africa
| | - Robert Peter Mason
- Department of Marine Sciences, University of Connecticut, Groton, Connecticut 06340, United States
| | - Katrina MacSween
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change, Toronto, Ontario M3H 5T4, Canada
| | - Sreekanth Vijayakumaran Nair
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana SI-1000, Slovenia
- Jožef Stefan International Postgraduate School, Jožef Stefan Institute, Ljubljana SI-1000, Slovenia
| | - Ly Sy Phu Nguyen
- Faculty of Environment, University of Science, Vietnam National University, Ho Chi Minh City 700000,Vietnam
| | - Trevor O'Neil
- Bingham Research Center, Utah State University, Vernal, Utah 84078, United States
| | - Jonas Sommar
- Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550009, China
| | - Peter Weiss-Penzias
- University of California-Santa Cruz, Santa Cruz, California 95064, United States
| | - Lei Zhang
- School of the Environment, Nanjing University, Nanjing 210023, China
| | - Igor Živković
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana SI-1000, Slovenia
- Jožef Stefan International Postgraduate School, Jožef Stefan Institute, Ljubljana SI-1000, Slovenia
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2
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Božič D, Horvat M. Insights into seasonal variations in mercury isotope composition of lichens. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 340:122740. [PMID: 37865331 DOI: 10.1016/j.envpol.2023.122740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 09/24/2023] [Accepted: 10/12/2023] [Indexed: 10/23/2023]
Abstract
Lichens are commonly used to assess mercury (Hg) concentrations in air because of their cost-effectiveness. However, recent research has revealed temporal variations in the isotopic composition of Hg. Previous work on this topic leaves open questions about the repeatability of data over multiple seasons, different types of sampling (transplantation or in-situ collection), and diverse locations. This study aims to address these issues by conducting a high-frequency sampling campaign of in-situ and transplanted lichens and atmospheric particulate matter (APM). Sampling sites included a range of areas, from pristine to Hg-contaminated sites. Isotopic analysis showed that the isotopic composition of Hg in lichens undergoes mass-dependent fractionation and changes with time. The heaviest isotopic composition was observed in summer and the lightest in winter. These trends were consistent across polluted and unpolluted environments, as well as in both in-situ and transplanted lichens and in APM. The results further indicated towards a correlation between changes in Hg concentrations and isotopic composition in lichens and environmental factors. All of these variables seem to be changing at the same frequency and may have not just correlation but also causation relationship. Environmental factors seem to be influencing the Hg concentrations and isotopic composition. The summer high temperatures might be influencing the heavier isotopic fingerprint observed in lichens during the same season. Similarities with APM-bound Hg suggest a common underlying mechanism. This study highlights the importance of considering temporal and seasonal trends, as well as the method of lichen sampling, when interpreting results. Researchers using lichens as proxies for atmospheric Hg concentrations or isotope ratios should consider these findings when designing their studies.
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Affiliation(s)
- Dominik Božič
- Department of Environmental Science, Jožef Stefan Institute, Jamova Street 39, Ljubljana, Slovenia; Jožef Stefan International Postgraduate School, Jamova Street 39, Ljubljana, Slovenia
| | - Milena Horvat
- Department of Environmental Science, Jožef Stefan Institute, Jamova Street 39, Ljubljana, Slovenia; Jožef Stefan International Postgraduate School, Jamova Street 39, Ljubljana, Slovenia.
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3
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Vreedzaam A, Ouboter P, Hindori-Mohangoo AD, Lepak R, Rumschlag S, Janssen S, Landburg G, Shankar A, Zijlmans W, Lichtveld MY, Wickliffe JK. Contrasting mercury contamination scenarios and site susceptibilities confound fish mercury burdens in Suriname, South America. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 336:122447. [PMID: 37648055 PMCID: PMC10756560 DOI: 10.1016/j.envpol.2023.122447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 08/05/2023] [Accepted: 08/22/2023] [Indexed: 09/01/2023]
Abstract
In Suriname, mercury (Hg) use has recently increased because of gold mining, which has put fish-reliant communities (e.g., Indigenous and Tribal) at risk of enhanced Hg exposure through the riverine fish these communities consume. To quantify how the magnitude of these risks change according to location and time, we measured total mercury (HgT) in fish at sites downstream and upstream of an artisanal and small-scale gold mining (ASGM) operation in 2004-2005 and in 2017-2018. We tested whether fish HgT burdens over dynamic ranges were increased. Surprisingly, our findings did not support broadly increased fish Hg burden over time or that proximity to ASGM was diagnostic to fish HgT-burden. Subsequently, we elected to test the HgT stable isotope ratios on a set of freshly collected 2020 fish to determine whether differences in Hg source and delivery pathways might cofound results. We found that remote unmined sites were more susceptible to gaseous elemental Hg deposition pathways, leading to enhanced risk of contamination, whereas ASGM proximate sites were not. These results highlight that elemental mercury releases from ASGM practices may have significant impact on fish-reliant communities that are far removed from ASGM point source contamination.
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Affiliation(s)
- Arioené Vreedzaam
- Amazon Sustainable Landscapes Program, United Nations Development Programme Suriname, Paramaribo, Suriname
| | - Paul Ouboter
- Institute of Neotropical Wildlife and Environmental Studies, Paramaribo, Suriname
| | | | - Ryan Lepak
- US Environmental Protection Agency Office of Research and Development, Duluth, MN USA
| | - Samantha Rumschlag
- US Environmental Protection Agency Office of Research and Development, Duluth, MN USA
| | - Sarah Janssen
- U.S. Geological Survey, Upper Midwest Water Science Center, USGS Mercury Research Laboratory, Madison, WI 53726, USA
| | - Gwen Landburg
- Environmental Laboratory, Anton de Kom University of Suriname, Paramaribo, Suriname
| | - Arti Shankar
- School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA, USA
| | - Wilco Zijlmans
- Faculty of Medical Sciences, Anton de Kom University of Suriname, Paramaribo, Suriname
| | | | - Jeffrey K Wickliffe
- School of Public Health, University of Alabama at Birmingham, Birmingham, AL, USA.
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4
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Sun R, Cao F, Dai S, Shan B, Qi C, Xu Z, Li P, Liu Y, Zheng W, Chen J. Atmospheric Mercury Isotope Shifts in Response to Mercury Emissions from Underground Coal Fires. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023. [PMID: 37167064 DOI: 10.1021/acs.est.2c08637] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Pollutant emissions from coal fires have caused serious concerns in major coal-producing countries. Great efforts have been devoted to suppressing them in China, notably at the notorious Wuda Coalfield in Inner Mongolia. Recent surveys revealed that while fires in this coalfield have been nearly extinguished near the surface, they persist underground. However, the impacts of Hg volatilized from underground coal fires remain unclear. Here, we measured concentrations and isotope compositions of atmospheric Hg in both gaseous and particulate phases at an urban site near the Wuda Coalfield. The atmospheric Hg displayed strong seasonality in terms of both Hg concentrations (5-7-fold higher in fall than in winter) and isotope compositions. Combining characteristic isotope compositions of potential Hg sources and air mass trajectories, we conclude that underground coal fires were still emitting large amounts of Hg into the atmosphere that have been transported to the adjacent urban area in the prevailing downwind direction. The other local anthropogenic Hg emissions were only evident in the urban atmosphere when the arriving air masses did not pass directly through the coalfield. Our study demonstrates that atmospheric Hg isotope measurement is a useful tool for detecting concealed underground coal fires.
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Affiliation(s)
- Ruoyu Sun
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Fei Cao
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Shifeng Dai
- College of Geoscience and Survey Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China
| | - Bing Shan
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Cuicui Qi
- Anhui Academy of Eco-environmental Science Research, Hefei 230071, China
| | - Zhanjie Xu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Pengfei Li
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Yi Liu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Wang Zheng
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Jiubin Chen
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
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5
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Schneider L, Fisher JA, Diéguez MC, Fostier AH, Guimaraes JRD, Leaner JJ, Mason R. A synthesis of mercury research in the Southern Hemisphere, part 1: Natural processes. AMBIO 2023; 52:897-917. [PMID: 36943620 PMCID: PMC10073387 DOI: 10.1007/s13280-023-01832-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 11/30/2022] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
Recent studies demonstrate a short 3-6-month atmospheric lifetime for mercury (Hg). This implies Hg emissions are predominantly deposited within the same hemisphere in which they are emitted, thus placing increasing importance on considering Hg sources, sinks and impacts from a hemispheric perspective. In the absence of comprehensive Hg data from the Southern Hemisphere (SH), estimates and inventories for the SH have been drawn from data collected in the NH, with the assumption that the NH data are broadly applicable. In this paper, we centre the uniqueness of the SH in the context of natural biogeochemical Hg cycling, with focus on the midlatitudes and tropics. Due to its uniqueness, Antarctica warrants an exclusive review of its contribution to the biogeochemical cycling of Hg and is therefore excluded from this review. We identify and describe five key natural differences between the hemispheres that affect the biogeochemical cycling of Hg: biome heterogeneity, vegetation type, ocean area, methylation hotspot zones and occurence of volcanic activities. We review the current state of knowledge of SH Hg cycling within the context of each difference, as well as the key gaps that impede our understanding of natural Hg cycling in the SH. The differences demonstrate the limitations in using NH data to infer Hg processes and emissions in the SH.
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Affiliation(s)
- Larissa Schneider
- School of Culture, History and Language. Australian National University, Coombs Bld 9 Fellows Rd, Acton. Canberra, ACT 2601 Australia
| | - Jenny A. Fisher
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522 Australia
| | - María C. Diéguez
- Instituto de Investigaciones en Biodiversidad y Medioambiente (Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad Nacional del Comahue), 1250 San Carlos de Bariloche (8400), Quintral Argentina
| | - Anne-Hélène Fostier
- Instituto de Química/Unicamp, Rua Josué de Castro, s/n – Cidade Universitária, Campinas, SP 13083-970 Brazil
| | - Jean R. D. Guimaraes
- Lab. de Traçadores, Inst. de Biofísica, Bloco G, CCS (Centro de Ciências da Saúde), Av. Carlos Chagas Filho 373, Rio de Janeiro, Ilha do Fundão CEP 21941-902 Brazil
| | - Joy J. Leaner
- Department of Environmental Affairs and Development Planning, Western Cape Government, 1 Dorp Street, Western Cape, Cape Town, 8001 South Africa
| | - Robert Mason
- Department of Marine Sciences, University of Connecticut, 1080 Shennecossett Road, Groton, CT 06340 USA
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6
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Tate MT, Janssen SE, Lepak RF, Flucke L, Krabbenhoft DP. National-Scale Assessment of Total Gaseous Mercury Isotopes Across the United States. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2023; 128:1-15. [PMID: 37593527 PMCID: PMC10430761 DOI: 10.1029/2022jd038276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 04/01/2023] [Indexed: 08/19/2023]
Abstract
With the 2011 promulgation of the Mercury and Air Toxics Standards by the U.S. Environmental Protection Agency, and the successful negotiation by the United Nations Environment Program of the Minamata Convention, emissions of mercury (Hg) have declined in the United States. While the declines in atmospheric Hg concentrations in North America are encouraging, linking the declines to changing domestic and global source portfolios remains challenging. To address these research gaps, the U.S. Geological Survey initiated the first national-scale effort to establish a baseline of total gaseous mercury stable isotope values at 31 sites distributed across the United States. Results indicated that unique Hg sources, such as Hg evasion from an elemental Hg contaminated site or free tropospheric intrusions in high altitude sites, were distinguishable from background atmospheric values. Minor gradients were observed across the nation, with regions of heavy industrial activity demonstrating lower δ 202 Hg , but no consistent changes in other isotopes such as Δ 199 Hg and Δ 200 Hg were observed. Furthermore, δ 202 Hg was impacted by foliar uptake and senescence but trends varied between forested regions in the northeastern and midwestern United States. These data demonstrate regional emission sources and other environmental variables can impact total gaseous Hg (TGM) isotope values, highlighting the need to characterize atmospheric Hg isotopes over larger geographical areas to evaluate changes related to national and international Hg regulations.
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Affiliation(s)
- Michael T Tate
- Upper Midwest Water Science Center, U.S. Geological Survey, Madison, WI, USA
| | - Sarah E Janssen
- Upper Midwest Water Science Center, U.S. Geological Survey, Madison, WI, USA
| | - Ryan F Lepak
- Center for Computational Toxicology and Exposure, Great Lakes Toxicology and Ecology Division, U.S. Environmental Protection Agency Office of Research and Development, Duluth, MN, USA
| | - Laura Flucke
- Upper Midwest Water Science Center, U.S. Geological Survey, Madison, WI, USA
- University of Wisconsin, Atmospheric and Oceanic Science, Madison, WI, USA
| | - David P Krabbenhoft
- Upper Midwest Water Science Center, U.S. Geological Survey, Madison, WI, USA
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7
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Božič D, Živković I, Hudobivnik MJ, Kotnik J, Amouroux D, Štrok M, Horvat M. Fractionation of mercury stable isotopes in lichens. CHEMOSPHERE 2022; 309:136592. [PMID: 36167212 DOI: 10.1016/j.chemosphere.2022.136592] [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: 05/25/2022] [Revised: 09/02/2022] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
Bio-monitoring of mercury (Hg) in air using transplanted and in-situ lichens was conducted at three locations in Slovenia: (I) the town of Idrija in the area of the former Hg mine, where Hg contamination is well known; (II) Anhovo, a settlement with a cement production plant, which is a source of Hg contamination, and (III) Pokljuka, a part of a national park. Lichens from Pokljuka were transplanted to different sites and sampled four times-once per season, from January 2020 to February 2021. Lichens were set on tree branches, fences, and under cover, allowing them to be exposed to different environmental conditions (e.g., light and rain). The in-situ lichens were sampled at the beginning and the end of the sampling period. The highest concentrations were in the Idrija area, which was consistent with previous research. Significant mass-dependent fractionation has been observed in transplanted lichens during summer period. The δ202Hg changed from -3.0‰ in winter to -1.0‰ in summer and dropped again to the same value in winter the following year. This trend was observed in all samples, except those from the most polluted Idrija sampling site, which was in the vicinity of the former Hg ore-smelting plant. This was likely due to large amounts of Hg originating from polluted soil close to the former smelting plant with a distinct isotopic fingerprint in this local area. The Δ199Hg in transplanted lichens ranged from -0.5‰ to -0.1‰ and showed no seasonal trends. These findings imply that seasonality, particularly in summer months, may affect the isotopic fractionation of Hg and should be considered in the sampling design and data interpretation. This trend was thus described in lichens for the first time. The mechanism behind such change is not yet fully understood.
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Affiliation(s)
- Dominik Božič
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Street 39, Ljubljana, Slovenia; Jožef Stefan International Postgraduate School, Jamova Street 39, Ljubljana, Slovenia
| | - Igor Živković
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Street 39, Ljubljana, Slovenia
| | - Marta Jagodic Hudobivnik
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Street 39, Ljubljana, Slovenia
| | - Jože Kotnik
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Street 39, Ljubljana, Slovenia
| | - David Amouroux
- The Institute of Analytical Sciences and Physico-Chemistry for Environment and Materials, 2 Avenue Pierre Angot, Pau Cedex 9, France
| | - Marko Štrok
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Street 39, Ljubljana, Slovenia; Jožef Stefan International Postgraduate School, Jamova Street 39, Ljubljana, Slovenia
| | - Milena Horvat
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Street 39, Ljubljana, Slovenia; Jožef Stefan International Postgraduate School, Jamova Street 39, Ljubljana, Slovenia.
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8
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Mercury isotope evidence for Arctic summertime re-emission of mercury from the cryosphere. Nat Commun 2022; 13:4956. [PMID: 36002442 PMCID: PMC9402541 DOI: 10.1038/s41467-022-32440-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 07/29/2022] [Indexed: 11/28/2022] Open
Abstract
During Arctic springtime, halogen radicals oxidize atmospheric elemental mercury (Hg0), which deposits to the cryosphere. This is followed by a summertime atmospheric Hg0 peak that is thought to result mostly from terrestrial Hg inputs to the Arctic Ocean, followed by photoreduction and emission to air. The large terrestrial Hg contribution to the Arctic Ocean and global atmosphere has raised concern over the potential release of permafrost Hg, via rivers and coastal erosion, with Arctic warming. Here we investigate Hg isotope variability of Arctic atmospheric, marine, and terrestrial Hg. We observe highly characteristic Hg isotope signatures during the summertime peak that reflect re-emission of Hg deposited to the cryosphere during spring. Air mass back trajectories support a cryospheric Hg emission source but no major terrestrial source. This implies that terrestrial Hg inputs to the Arctic Ocean remain in the marine ecosystem, without substantial loss to the global atmosphere, but with possible effects on food webs. Arctic warming thaws permafrost, leading to enhanced soil mercury transport to the Arctic Ocean. Mercury isotope signatures in arctic rivers, ocean and atmosphere suggest that permafrost mercury is buried in marine sediment and not emitted to the global atmosphere
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9
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Nipen M, Jørgensen SJ, Bohlin-Nizzetto P, Borgå K, Breivik K, Mmochi AJ, Mwakalapa EB, Quant MI, Schlabach M, Vogt RD, Wania F. Mercury in air and soil on an urban-rural transect in East Africa. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2022; 24:921-931. [PMID: 35583028 DOI: 10.1039/d2em00040g] [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
There are large knowledge gaps concerning concentrations, sources, emissions, and spatial trends of mercury (Hg) in the atmosphere in developing regions of the Southern Hemisphere, particularly in urban areas. Filling these gaps is a prerequisite for assessing the effectiveness of international regulation and for enabling a better understanding of the global transport of Hg in the environment. Here we use a passive sampling technique to study the spatial distribution of gaseous elemental Hg (Hg(0), GEM) and assess emission sources in and around Dar es Salaam, Tanzania's largest city. Included in the study were the city's main municipal waste dumpsite and an e-waste processing facility as potential sources of GEM. To complement the GEM data and for a better overview of the Hg contamination status of Dar es Salaam, soil samples were collected from the same locations where passive air samplers were deployed and analysed for total Hg. Overall, GEM concentrations ranged between <0.86 and 5.34 ng m-3, indicating significant local sources within the urban area. The municipal waste dumpsite and e-waste site had GEM concentrations elevated above the background, at 2.41 and 1.77 ng m-3, respectively. Hg concentrations in soil in the region (range 0.0067 to 0.098 mg kg-1) were low compared to those of other urban areas and were not correlated with atmospheric GEM concentrations. This study demonstrates that GEM is a significant environmental issue in the urban region of Dar es Salaam. Further studies from urban areas in the Global South are needed to better identify sources of GEM.
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Affiliation(s)
- Maja Nipen
- Centre for Biogeochemistry in the Anthropocene, Department of Chemistry, University of Oslo, P.O. Box 1033, 0315 Oslo, Norway.
- NILU-Norwegian Institute for Air Research, P.O. Box 100, 2027 Kjeller, Norway
| | - Susanne Jøntvedt Jørgensen
- Centre for Biogeochemistry in the Anthropocene, Department of Chemistry, University of Oslo, P.O. Box 1033, 0315 Oslo, Norway.
| | | | - Katrine Borgå
- Aquatic Biology and Toxicology and Centre for Biogeochemistry in the Anthropocene, Department of Biosciences, University of Oslo, P.O. Box 1066, 0316 Oslo, Norway
| | - Knut Breivik
- Centre for Biogeochemistry in the Anthropocene, Department of Chemistry, University of Oslo, P.O. Box 1033, 0315 Oslo, Norway.
- NILU-Norwegian Institute for Air Research, P.O. Box 100, 2027 Kjeller, Norway
| | - Aviti John Mmochi
- Institute for Marine Sciences, University of Dar Es Salaam, Zanzibar, Tanzania
| | | | - M Isabel Quant
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265, Military Trail, ON MIC 1A4 Toronto, Canada
| | - Martin Schlabach
- NILU-Norwegian Institute for Air Research, P.O. Box 100, 2027 Kjeller, Norway
| | | | - Frank Wania
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265, Military Trail, ON MIC 1A4 Toronto, Canada
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10
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Snow MA, Feigis M, Lei YD, Mitchell CPJ, Wania F. Development, characterization, and testing of a personal passive sampler for measuring inhalation exposure to gaseous elemental mercury. ENVIRONMENT INTERNATIONAL 2021; 146:106264. [PMID: 33227582 DOI: 10.1016/j.envint.2020.106264] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/02/2020] [Accepted: 11/03/2020] [Indexed: 06/11/2023]
Abstract
Inhalation of gaseous elemental mercury (GEM) is an occupational exposure concern for workers handling elemental mercury or mercury-containing waste. GEM is also often present near historically mercury-contaminated sites, potentially resulting in low-level, chronic exposure of the wider population. Here we introduce a passive sampler for personal GEM monitoring which combines a radial porous diffusive barrier with an activated carbon sorbent. A total mercury analyzer is used to quantify GEM sorbed to the carbon by thermal decomposition, amalgamation, and atomic absorption spectroscopy. A sampling rate of 0.070 m3/day was determined by calibrating the sampler at low and high concentrations. Deployments lasting 8 h result in limits of quantification well below 200 ng/m3. The sampler has a measurement range of at least four orders of magnitude. Derived air concentrations were not statistically significantly different from those obtained by active air sampling but were more precise than those obtained using a personal pump. If properly stored, the sampler maintains low blank levels in high GEM environments. Affordability, sturdiness, simplicity, and the wide availability of total mercury analyzers make this sampler highly suited for monitoring GEM inhalation exposure, including in developing countries.
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Affiliation(s)
- Melanie A Snow
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Michelle Feigis
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Ying Duan Lei
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Carl P J Mitchell
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - Frank Wania
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada.
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