1
|
Elgiar TR, Lyman SN, Andron TD, Gratz L, Hallar AG, Horvat M, Vijayakumaran Nair S, O'Neil T, Volkamer R, Živković I. Traceable Calibration of Atmospheric Oxidized Mercury Measurements. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:10706-10716. [PMID: 38850513 DOI: 10.1021/acs.est.4c02209] [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: 06/10/2024]
Abstract
Most previous measurements of oxidized mercury were collected using a method now known to be biased low. In this study, a dual-channel system with an oxidized mercury detection limit of 6-12 pg m-3 was deployed alongside a permeation tube-based automated calibrator at a mountain top site in Steamboat Springs Colorado, USA, in 2021 and 2022. Permeation tubes containing elemental mercury and mercury halides were characterized via an International System of Units (SI)-traceable gravimetric method and gas chromatography/mass spectrometry before deployment in the calibrator. The dual-channel system recovered 97 ± 4 and 100 ± 8% (±standard deviation) of injected elemental mercury and HgBr2, respectively. Total Hg permeation rates and Hg speciation from the gravimetric method, the chromatography system, the dual-channel system, and an independent SI-traceable measurement method performed at the Jožef Stefan Institute laboratory were all comparable within the respective uncertainties of each method. These are the first measurements of oxidized mercury at low environmental concentrations that have been verified against an SI-traceable calibration system in field conditions while sampling ambient air, and they show that accurate, routinely calibrated oxidized mercury measurements are achievable.
Collapse
Affiliation(s)
- Tyler R Elgiar
- Bingham Research Center, Utah State University, Vernal, Utah 84078, United States
| | - 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
| | - Teodor D Andron
- JoŽef Stefan Institute, Ljubljana 1000, Slovenia
- JoŽef Stefan International Postgraduate School, Ljubljana 1000, Slovenia
| | - Lynne Gratz
- Reed College, Portland, Oregon 97202, United States
| | - A Gannet Hallar
- Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah 84112, United States
| | - Milena Horvat
- JoŽef Stefan Institute, Ljubljana 1000, Slovenia
- JoŽef Stefan International Postgraduate School, Ljubljana 1000, Slovenia
| | - Sreekanth Vijayakumaran Nair
- JoŽef Stefan Institute, Ljubljana 1000, Slovenia
- JoŽef Stefan International Postgraduate School, Ljubljana 1000, Slovenia
| | - Trevor O'Neil
- Bingham Research Center, Utah State University, Vernal, Utah 84078, United States
| | - Rainer Volkamer
- Department of Chemistry & CIRES, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Igor Živković
- JoŽef Stefan Institute, Ljubljana 1000, Slovenia
- JoŽef Stefan International Postgraduate School, Ljubljana 1000, Slovenia
| |
Collapse
|
2
|
Gustin MS, Dunham-Cheatham SM, Osterwalder S, Magand O, Dommergue A. What is the utility of measuring gaseous Hg II dry deposition using Aerohead samplers?: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 907:167895. [PMID: 37866618 DOI: 10.1016/j.scitotenv.2023.167895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/15/2023] [Accepted: 10/15/2023] [Indexed: 10/24/2023]
Abstract
The most efficient way to quantify HgII inputs to ecosystems is to measure wet and dry deposition. Wet deposition of HgII is determined by measuring Hg concentrations and the volume of precipitation. Dry deposition of HgII is determined through direct measurement and/or determined indirectly by measuring air concentrations and using model-generated deposition velocities. Here, data collected using an Aerohead sampler holding cation exchange membranes are summarized, and the utility of this method for understanding dry deposition, and other measurements and processes is discussed. This analysis includes information from publications, and recent data collected at Guadalupe Mountains National Park, Texas, USA, and Amsterdam Island, Southern Indian Ocean. This method primarily measures gaseous HgII and little particulate-bound Hg. The Aerohead method is useful for looking at large-scale trends in deposition, verifying Hg depletion events, calculating dry deposition velocities for compounds with specific chemistry, and identification of sources of HgII. At numerous locations in the western USA, deposition rates were greater at higher elevations due to elevated concentrations associated with long-range transport of atmospheric pollution. When used in tandem with the Reactive Mercury Active System or a dual-channel system, more accurate deposition velocities - that vary as a function of GOM compound chemistry - can be calculated.
Collapse
Affiliation(s)
- Mae Sexauer Gustin
- Department of Natural Resources and Environmental Science, University of Nevada, Reno.
| | - Sarrah M Dunham-Cheatham
- College of Biotechnology, Natural Resources and Environmental Science, University of Nevada, Reno
| | - Stefan Osterwalder
- Univ. Grenoble Alpes, CNRS, INRAE, IRD, Grenoble INP (Institute of Engineering and Management Univ. Grenoble Alpes), IGE, 38000 Grenoble, France; Department of Environmental Systems Science (D-USYS), Institute of Agricultural Sciences, ETH Zurich, Zurich, Switzerland
| | - Olivier Magand
- Observatoire des Sciences de l'Univers à La Réunion (OSU-R), UAR 3365, CNRS, Université de La Réunion, Météo France, 97744 Saint-Denis, La Réunion, France
| | - Aurélien Dommergue
- Univ. Grenoble Alpes, CNRS, INRAE, IRD, Grenoble INP (Institute of Engineering and Management Univ. Grenoble Alpes), IGE, 38000 Grenoble, France
| |
Collapse
|
3
|
Gustin MS, Dunham-Cheatham SM, Allen N, Choma N, Johnson W, Lopez S, Russell A, Mei E, Magand O, Dommergue A, Elgiar T. Observations of the chemistry and concentrations of reactive Hg at locations with different ambient air chemistry. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 904:166184. [PMID: 37586514 DOI: 10.1016/j.scitotenv.2023.166184] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Revised: 08/07/2023] [Accepted: 08/07/2023] [Indexed: 08/18/2023]
Abstract
The Hg research community needs methods to more accurately measure atmospheric Hg concentrations and chemistry. The Reactive Mercury Active System (RMAS) uses cation exchange, nylon, and PTFE membranes to determine reactive mercury (RM), gaseous oxidized mercury, and particulate-bound mercury (PBM) concentrations and chemistry. New data for Atlanta, Georgia (NRGT) demonstrated that particulate-bound Hg was dominant and the chemistry was primarily N and S HgII compounds. At Great Salt Lake, Utah (GSL), RM was predominately PBM, with NS > organics > halogen > O HgII compounds. At Guadalupe Mountains National Park, Texas (GUMO), halogenated compound concentrations were lowest when air interacting with the site was primarily derived from the Midwest, and highest when the air was sourced from Mexico. At Amsterdam Island, Southern Indian Ocean, compounds were primarily halogenated with some N, S, and organic HgII compounds potentially associated with biological activity. The GEOS-Chem model was applied to see if it predicted measurements at five field sites. Model values were higher than observations at GSL, slightly lower at NRGT, and observations were an order of magnitude higher than modeled values for GUMO and Reno, Nevada. In general, data collected from 13 locations indicated that N, S, and organic RM compounds were associated with city and forest locations, halogenated compounds were sourced from the marine boundary layer, and O compounds were associated with long-range transport. Data being developed currently, and in the past, suggest there are multiple forms of RM that modelers must consider, and PBM is an important component of RM.
Collapse
Affiliation(s)
- Mae Sexauer Gustin
- Department of Natural Resources & Environmental Science, University of Nevada, Reno, NV, USA.
| | | | - Natalie Allen
- Department of Natural Resources & Environmental Science, University of Nevada, Reno, NV, USA
| | - Nicole Choma
- Department of Natural Resources & Environmental Science, University of Nevada, Reno, NV, USA
| | - William Johnson
- Department of Geology & Geophysics, University of Utah, Salt Lake City, UT, USA
| | - Sam Lopez
- Department of Geology & Geophysics, University of Utah, Salt Lake City, UT, USA
| | - Armistead Russell
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Eric Mei
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Olivier Magand
- Univ. Grenoble Alpes, CNRS, INRAE, IRD, Grenoble INP(1), IGE, 38000 Grenoble, France; Observatoire des Sciences de l'Univers à La Réunion (OSU-R), UAR 3365, CNRS, Université de La Réunion, Météo France, 97744 Saint-Denis, La Réunion, France
| | - Aurélien Dommergue
- Univ. Grenoble Alpes, CNRS, INRAE, IRD, Grenoble INP(1), IGE, 38000 Grenoble, France
| | - Tyler Elgiar
- Bingham Research Center, Utah State University, Vernal, UT, USA
| |
Collapse
|
4
|
Magand O, Angot H, Bertrand Y, Sonke JE, Laffont L, Duperray S, Collignon L, Boulanger D, Dommergue A. Over a decade of atmospheric mercury monitoring at Amsterdam Island in the French Southern and Antarctic Lands. Sci Data 2023; 10:836. [PMID: 38016986 PMCID: PMC10684586 DOI: 10.1038/s41597-023-02740-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 11/09/2023] [Indexed: 11/30/2023] Open
Abstract
The Minamata Convention, a global and legally binding treaty that entered into force in 2017, aims to protect human health and the environment from harmful mercury (Hg) effects by reducing anthropogenic Hg emissions and environmental levels. The Conference of the Parties is to periodically evaluate the Convention's effectiveness, starting in 2023, using existing monitoring data and observed trends. Monitoring atmospheric Hg levels has been proposed as a key indicator. However, data gaps exist, especially in the Southern Hemisphere. Here, we present over a decade of atmospheric Hg monitoring data at Amsterdam Island (37.80°S, 77.55°E), in the remote southern Indian Ocean. Datasets include gaseous elemental and oxidised Hg species ambient air concentrations from either active/continuous or passive/discrete acquisition methods, and annual total Hg wet deposition fluxes. These datasets are made available to the community to support policy-making and further scientific advancements.
Collapse
Affiliation(s)
- Olivier Magand
- Observatoire des Sciences de l'Univers à La Réunion (OSU-R), UAR 3365, CNRS, Université de La Réunion, Météo France, 97744, Saint-Denis, La Réunion, France
- Univ. Grenoble Alpes, CNRS, INRAE, IRD, Grenoble INP, IGE, Grenoble, France
| | - Hélène Angot
- Univ. Grenoble Alpes, CNRS, INRAE, IRD, Grenoble INP, IGE, Grenoble, France.
| | - Yann Bertrand
- Univ. Grenoble Alpes, CNRS, INRAE, IRD, Grenoble INP, IGE, Grenoble, France
| | - Jeroen E Sonke
- Géosciences Environnement Toulouse, CNRS/IRD, Université Paul Sabatier Toulouse 3, Toulouse, France
| | - Laure Laffont
- Géosciences Environnement Toulouse, CNRS/IRD, Université Paul Sabatier Toulouse 3, Toulouse, France
| | - Solène Duperray
- Univ. Grenoble Alpes, CNRS, INRAE, IRD, Grenoble INP, IGE, Grenoble, France
| | - Léa Collignon
- Univ. Grenoble Alpes, CNRS, INRAE, IRD, Grenoble INP, IGE, Grenoble, France
| | | | - Aurélien Dommergue
- Univ. Grenoble Alpes, CNRS, INRAE, IRD, Grenoble INP, IGE, Grenoble, France.
| |
Collapse
|
5
|
Dunham-Cheatham SM, Lyman S, Gustin MS. Comparison and calibration of methods for ambient reactive mercury quantification. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 856:159219. [PMID: 36202360 DOI: 10.1016/j.scitotenv.2022.159219] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 09/28/2022] [Accepted: 09/30/2022] [Indexed: 06/16/2023]
Abstract
Gaseous oxidized mercury (GOM) is the dominant form of atmospheric mercury (Hg) deposited and sequestered within ecosystems. Thus, accurate, calibrated measurements of GOM are needed. Here, two active membrane-based collection systems (RMAS) were used to determine GOM and particulate-bound Hg (PBM), as well as reactive Hg (RM = GOM + PBM), and compared with two dual-channel systems (DCS) and a Tekran 2537/1130 speciation system. The DCS measured operationally defined GOM by difference, using concentrations of gaseous elemental Hg (GEM) and total gaseous Hg. One DCS was linked to a custom-built, automated calibration system that permeated GEM, HgBr2, or HgCl2. The five systems were co-located for one-year to develop a dataset that would allow for understanding limitations of each system, and assessing measurement accuracy and long-term precision of the calibrator. The Tekran system measured ~14.5 % of the GOM measured by the other systems. The USU and UNR DCS and RMAS were significantly correlated, but the DCS was 50 and 30 % higher, respectively, than the RMAS. The calibrator performed consistently in the field and lab, and the DCS fully recovered GOM injected by the calibrator. Since the uncalibrated DCS measured the same concentrations as the calibrated DCS, they are both accurate methods for measuring RM and/or GOM. Some loss occurred from the RMAS membranes. SYNOPSIS: Accurate and calibrated measurements of atmospheric reactive mercury using membranes and two dual-channel systems.
Collapse
Affiliation(s)
- Sarrah M Dunham-Cheatham
- Department of Natural Resources & Environmental Science, University of Nevada, Reno, 1664 N. Virginia Street, Mail Stop 186, Reno, NV 89557, USA.
| | - Seth Lyman
- Bingham Research Center, Utah State University, 320 N Aggie Blvd, Vernal, UT 84078, USA; Department of Chemistry and Biochemistry, Utah State University, 0300 Old Main Hill, Logan, UT 84322, USA
| | - Mae Sexauer Gustin
- Department of Natural Resources & Environmental Science, University of Nevada, Reno, 1664 N. Virginia Street, Mail Stop 186, Reno, NV 89557, USA
| |
Collapse
|
6
|
Zhang L, Zhang G, Zhou P, Zhao Y. A Review of Dry Deposition Schemes for Speciated Atmospheric Mercury. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2022; 110:16. [PMID: 36525086 DOI: 10.1007/s00128-022-03641-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 10/20/2022] [Indexed: 06/17/2023]
Abstract
This study reviewed the existing framework of dry deposition schemes for speciated atmospheric mercury. As the most commonly used methods for mercury dry deposition estimation, the big-leaf resistance scheme for gaseous oxidized mercury (GOM), the size distribution regarded resistance scheme for particulate bound mercury (PBM), and the bidirectional air-surface exchange scheme for gaseous elemental mercury (GEM) were introduced in detail. Sensitivity analysis were conducted to quantitatively identify the key parameters for the estimation of speciated mercury dry deposition velocities. The dry deposition velocity of GOM was found to be sensitive to the wind speed and some land use related parameters. The chemical forms of GOM could have a significant impact on the dry deposition velocity. The dry deposition velocity of PBM is sensitive to the mass fraction of PBM in coarse particles, while that of GEM is most sensitive to air temperature. Future research needs were proposed accordingly.
Collapse
Affiliation(s)
- Lei Zhang
- School of the Environment and State Key Laboratory of Pollution Control and Resource Reuse, Nanjing University, 163 Xianlin Avenue, Nanjing, 210023, Jiangsu, China.
- Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology (CICAEET), Nanjing University of Information Science and Technology, Nanjing, 210044, Jiangsu, China.
| | - Guichen Zhang
- School of the Environment and State Key Laboratory of Pollution Control and Resource Reuse, Nanjing University, 163 Xianlin Avenue, Nanjing, 210023, Jiangsu, China
| | - Peisheng Zhou
- School of the Environment and State Key Laboratory of Pollution Control and Resource Reuse, Nanjing University, 163 Xianlin Avenue, Nanjing, 210023, Jiangsu, China
| | - Yu Zhao
- School of the Environment and State Key Laboratory of Pollution Control and Resource Reuse, Nanjing University, 163 Xianlin Avenue, Nanjing, 210023, Jiangsu, China
- Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology (CICAEET), Nanjing University of Information Science and Technology, Nanjing, 210044, Jiangsu, China
| |
Collapse
|
7
|
Year-round trace gas measurements in the central Arctic during the MOSAiC expedition. Sci Data 2022; 9:723. [PMID: 36434022 PMCID: PMC9700757 DOI: 10.1038/s41597-022-01769-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 10/11/2022] [Indexed: 11/26/2022] Open
Abstract
Despite the key role of the Arctic in the global Earth system, year-round in-situ atmospheric composition observations within the Arctic are sparse and mostly rely on measurements at ground-based coastal stations. Measurements of a suite of in-situ trace gases were performed in the central Arctic during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition. These observations give a comprehensive picture of year-round near-surface atmospheric abundances of key greenhouse and trace gases, i.e., carbon dioxide, methane, nitrous oxide, ozone, carbon monoxide, dimethylsulfide, sulfur dioxide, elemental mercury, and selected volatile organic compounds (VOCs). Redundancy in certain measurements supported continuity and permitted cross-evaluation and validation of the data. This paper gives an overview of the trace gas measurements conducted during MOSAiC and highlights the high quality of the monitoring activities. In addition, in the case of redundant measurements, merged datasets are provided and recommended for further use by the scientific community.
Collapse
|
8
|
Davis M, Lu J. Calibration Sources for Gaseous Oxidized Mercury: A Review of Source Design, Performance, and Operational Parameters. Crit Rev Anal Chem 2022:1-10. [PMID: 36223220 DOI: 10.1080/10408347.2022.2131373] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Mercury is a neurotoxin that, unlike many localized industrial pollutants, spreads globally through atmospheric transport. Mercury in the atmosphere is operationally partitioned into gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM), and particulate-bound mercury (TPM). Although GOM makes up only a small fraction of Hg in the free troposphere under normal conditions, its role in the dry and wet deposition of mercury makes GOM a significant species for understanding the transport and fate of mercury in the atmosphere. Although instruments for atmospheric mercury speciation are commercially available, significant uncertainty is associated with the current speciation methods, from sample collection to calibration, for GOM measurements. This paper examines the custom-made calibration sources that have been developed for GOM measuring instruments, evaluates the factors influencing the source performance, and synthesizes recommendations for the design and operation of GOM calibration sources in the future.
Collapse
Affiliation(s)
- Matthew Davis
- Department of Chemistry and Biology, Ryerson University, Toronto, Canada
| | - Julia Lu
- Department of Chemistry and Biology, Ryerson University, Toronto, Canada
| |
Collapse
|
9
|
Tang Y, Wang S, Li G, Han D, Liu K, Li Z, Wu Q. Elevated Gaseous Oxidized Mercury Revealed by a Newly Developed Speciated Atmospheric Mercury Monitoring System. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:7707-7715. [PMID: 35607915 DOI: 10.1021/acs.est.2c01011] [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
Gaseous oxidized mercury (Hg2+) monitoring is one of the largest challenges in the mercury research field, where existing methods cannot simultaneously satisfy the measurement requirements of both accuracy and time precision, especially in high-particulate environments. Here, we verified that dual-stage cation exchange membrane (CEM) sampler is incapable of gaseous elemental mercury (Hg0) uptake even if particulate matter is trapped on CEM, whereas the Hg2+ capture efficiency of the sampler is more than 90%. We then developed a Cation Exchange Membrane-Coupled Speciated Atmospheric Mercury Monitoring System (CSAMS) by coupling the dual-stage CEM sampler with the commercial Tekran 2537/1130/1135 system and configuring a new sampling and analysis procedure, so as to improve the monitoring accuracy of Hg2+ and ensure the simultaneous measurement of Hg0, Hg2+, and Hgp in 2 h time resolution. We deployed the CSAMS in urban Beijing in September 2021 and observed an unprecedented elevated Hg2+ during the daytime with an average amplitude of 510 pg m-3. Using a zero-dimensional box model, the elevated Hg2+ production rate was attributed to high atmospheric oxidant concentrations, Hg0 heterogeneous and interfacial oxidation processes on the surface of atmospheric particles, or potential unknown oxidants.
Collapse
Affiliation(s)
- Yi Tang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Shuxiao Wang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
- State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Guoliang Li
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Deming Han
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Kaiyun Liu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Zhijian Li
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Qingru Wu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
- State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| |
Collapse
|
10
|
Angot H, Rutkowski E, Sargent M, Wofsy SC, Hutyra LR, Howard D, Obrist D, Selin NE. Atmospheric mercury sources in a coastal-urban environment: a case study in Boston, Massachusetts, USA. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2021; 23:1914-1929. [PMID: 34739015 DOI: 10.1039/d1em00253h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Mercury (Hg) is an environmental toxicant dangerous to human health and the environment. Its anthropogenic emissions are regulated by global, regional, and local policies. Here, we investigate Hg sources in the coastal city of Boston, the third largest metropolitan area in the Northeastern United States. With a median of 1.37 ng m-3, atmospheric Hg concentrations measured from August 2017 to April 2019 were at the low end of the range reported in the Northern Hemisphere and in the range reported at North American rural sites. Despite relatively low ambient Hg concentrations, we estimate anthropogenic emissions to be 3-7 times higher than in current emission inventories using a measurement-model framework, suggesting an underestimation of small point and/or nonpoint emissions. We also test the hypothesis that a legacy Hg source from the ocean contributes to atmospheric Hg concentrations in the study area; legacy emissions (recycling of previously deposited Hg) account for ∼60% of Hg emitted annually worldwide (and much of this recycling takes place through the oceans). We find that elevated concentrations observed during easterly oceanic winds can be fully explained by low wind speeds and recirculating air allowing for accumulation of land-based emissions. This study suggests that the influence of nonpoint land-based emissions may be comparable in size to point sources in some regions and highlights the benefits of further top-down studies in other areas.
Collapse
Affiliation(s)
- Hélène Angot
- Institute for Data, Systems, and Society, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Extreme Environments Research Laboratory, École Polytechnique Fédérale de Lausanne (EPFL) Valais, Wallis, Sion, Switzerland
| | - Emma Rutkowski
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Maryann Sargent
- School of Engineering and Applied Science, Harvard University, Cambridge, MA, USA
| | - Steven C Wofsy
- School of Engineering and Applied Science, Harvard University, Cambridge, MA, USA
| | - Lucy R Hutyra
- Department of Earth and Environment, Boston University, Boston, MA, USA
| | - Dean Howard
- Department of Environmental, Earth, and Atmospheric Sciences, University of Massachusetts-Lowell, MA, USA
- Institute of Arctic and Alpine Research, University of Colorado Boulder, Boulder, CO, USA
| | - Daniel Obrist
- Department of Environmental, Earth, and Atmospheric Sciences, University of Massachusetts-Lowell, MA, USA
| | - Noelle E Selin
- Institute for Data, Systems, and Society, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| |
Collapse
|
11
|
Wu X, Duan Y, Meng J, Geng X, Shen A, Hu J. Experimental Study on the Mercury Removal of a H 2S-Modified Fe 2O 3 Adsorbent. Ind Eng Chem Res 2021. [DOI: 10.1021/acs.iecr.1c01998] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xinyu Wu
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Jiangsu 210096, China
| | - Yufeng Duan
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Jiangsu 210096, China
| | - Jialin Meng
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Jiangsu 210096, China
| | - Xinze Geng
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Jiangsu 210096, China
| | - Ao Shen
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Jiangsu 210096, China
| | - Jiwei Hu
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Jiangsu 210096, China
| |
Collapse
|
12
|
Gačnik J, Živković I, Ribeiro Guevara S, Jaćimović R, Kotnik J, Horvat M. Validating an Evaporative Calibrator for Gaseous Oxidized Mercury. SENSORS 2021; 21:s21072501. [PMID: 33916694 PMCID: PMC8038396 DOI: 10.3390/s21072501] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/30/2021] [Accepted: 04/01/2021] [Indexed: 11/20/2022]
Abstract
Understanding atmospheric mercury chemistry is the key for explaining the biogeochemical cycle of mercury and for improving the predictive capability of computational models. Increased efforts are being made to ensure comparable Hg speciation measurements in the air through establishing metrological traceability. While traceability for elemental mercury has been recently set, this is by no means the case for gaseous oxidized mercury (GOM). Since a calibration unit suitable for traceable GOM calibrations based on evaporation of HgCl2 solution was recently developed, the purpose of our work was to extensively evaluate its performance. A highly specific and sensitive 197Hg radiotracer was used for validation over a wide range of concentrations. By comparing experimental and calculated values, we obtained recoveries for the calibration unit. The average recoveries ranged from 88.5% for 1178 ng m−3 HgCl2 gas concentration to 39.4% for 5.90 ng m−3 HgCl2 gas concentration. The losses were due to the adsorption of oxidized Hg on the inner walls of the calibrator and tubing. An adsorption isotherm was applied to estimate adsorption enthalpy (ΔHads); a ΔHads value of −12.33 kJ mol−1 was obtained, suggesting exothermal adsorption. The results of the calibrator performance evaluation suggest that a newly developed calibration unit is only suitable for concentrations of HgCl2 higher than 1 µg m−3. The concentration dependence of recoveries prevents the system from being used for calibration of instruments for ambient GOM measurements. Moreover, the previously assessed uncertainty of this unit at µg m−3 level (2.0%, k = 2) was re-evaluated by including uncertainty related to recovery and was found to be 4.1%, k = 2. Calibrator performance was also evaluated for HgBr2 gas calibration; the recoveries were much lower for HgBr2 gas than for HgCl2 gas even at a high HgBr2 gas concentration (>1 µg m−3). As HgBr2 is often used as a proxy for various atmospheric HgBr species, the suitability of the unit for such calibration must be further developed.
Collapse
Affiliation(s)
- Jan Gačnik
- Jožef Stefan International Postgraduate School, Jamova Cesta 39, 1000 Ljubljana, Slovenia;
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia; (I.Ž.); (R.J.); (J.K.)
| | - Igor Živković
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia; (I.Ž.); (R.J.); (J.K.)
| | - Sergio Ribeiro Guevara
- Laboratorio de Análisis por Activación Neutrónica, Centro Atómico Bariloche, Av. Bustillo km 9.5, Bariloche 8400, Argentina;
| | - Radojko Jaćimović
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia; (I.Ž.); (R.J.); (J.K.)
| | - Jože Kotnik
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia; (I.Ž.); (R.J.); (J.K.)
| | - Milena Horvat
- Jožef Stefan International Postgraduate School, Jamova Cesta 39, 1000 Ljubljana, Slovenia;
- Department of Environmental Sciences, Jožef Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia; (I.Ž.); (R.J.); (J.K.)
- Correspondence: ; Tel.: +386-1-588-53-55
| |
Collapse
|
13
|
Gustin MS, Dunham-Cheatham SM, Zhang L, Lyman S, Choma N, Castro M. Use of Membranes and Detailed HYSPLIT Analyses to Understand Atmospheric Particulate, Gaseous Oxidized, and Reactive Mercury Chemistry. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:893-901. [PMID: 33404225 DOI: 10.1021/acs.est.0c07876] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The atmosphere is the primary pathway by which mercury enters ecosystems. Despite the importance of atmospheric deposition, concentrations and chemistry of gaseous oxidized (GOM) and particulate-bound (PBM) mercury are poorly characterized. Here, three membranes (cation exchange (CEM), nylon, and poly(tetrafluoroethylene) (PTFE) membranes) were used as a means for quantification of concentrations and identification of the chemistry of GOM and PBM. Detailed HYSPLIT analyses were used to determine sources of oxidants forming reactive mercury (RM = PBM + GOM). Despite the coarse sampling resolution (1-2 weeks), a gradient in chemistry was observed, with halogenated compounds dominating over the Pacific Ocean, and continued influence from the marine boundary layer in Nevada and Utah with a periodic occurrence in Maryland. Oxide-based RM compounds arrived at continental locations via long-range transport. Nitrogen, sulfur, and organic RM compounds correlated with regional and local air masses. RM concentrations were highest over the ocean and decreased moving from west to east across the United States. Comparison of membrane concentrations demonstrated that the CEM provided a quantitative measure of RM concentrations and PTFE membranes were useful for collecting PBM. Nylon membranes do not retain all compounds with equal efficiency in ambient air, and an alternate desorption surface is needed.
Collapse
Affiliation(s)
- Mae Sexauer Gustin
- Department of Natural Resources and Environmental Science, University of Nevada, Reno, Nevada 89557, United States
| | - Sarrah M Dunham-Cheatham
- Department of Natural Resources and Environmental Science, University of Nevada, Reno, Nevada 89557, United States
| | - Lei Zhang
- School of the Environment, Nanjing University, Nanjing 210023, Jiangsu, China
| | - Seth Lyman
- Bingham Research Center, Utah State University, Vernal, Utah 84322, United States
| | - Nicole Choma
- Department of Natural Resources and Environmental Science, University of Nevada, Reno, Nevada 89557, United States
| | - Mark Castro
- Appalachian Laboratory, University of Maryland Center for Environmental Science, Frostburg, Maryland 21532, United States
| |
Collapse
|
14
|
Miller MB, Howard DA, Pierce AM, Cook KR, Keywood M, Powell J, Gustin MS, Edwards GC. Atmospheric reactive mercury concentrations in coastal Australia and the Southern Ocean. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 751:141681. [PMID: 32861947 DOI: 10.1016/j.scitotenv.2020.141681] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 08/11/2020] [Accepted: 08/11/2020] [Indexed: 06/11/2023]
Abstract
Mercury (Hg), especially reactive Hg (RM), data from the Southern Hemisphere (SH) are limited. In this study, long-term measurements of both gaseous elemental Hg (GEM) and RM were made at two ground-based monitoring locations in Australia, the Cape Grim Baseline Air Pollution Station (CGBAPS) in Tasmania, and the Macquarie University Automatic Weather Station (MQAWS) in Sydney, New South Wales. Measurements were also made on board the Australian RV Investigator (RVI) during an ocean research voyage to the East Antarctic coast. GEM was measured using the standard Tekran® 2537 series analytical platform, and RM was measured using cation exchange membranes (CEM) in a filter-based sampling method. Overall mean RM concentrations at CGBAPS and MQAWS were 15.9 ± 6.7 pg m-3 and 17.8 ± 6.6 pg m-3, respectively. For the 10-week austral summer period on RVI, mean RM was 23.5 ± 6.7 pg m-3. RM concentrations at CGBAPS were seasonally invariable, while those at MQAWS were significantly different between summer and winter due to seasonal changes in synoptic wind patterns. During the RVI voyage, RM concentrations were relatively enhanced along the Antarctic coast (up to 30 pg m-3) and GEM concentrations were variable (0.2 to 0.9 ng m-3), suggesting periods of enrichment and depletion. Both RM and GEM concentrations were relatively lower while transiting the Southern Ocean farther north of Antarctica. RM concentrations measured in this study were higher in comparison to most other reported measurements of RM in the global marine boundary layer (MBL), especially for remote SH locations. As observations of GEM and RM concentrations inform global ocean-atmosphere model simulations of the atmospheric Hg budget, our results have important implications for understanding of total atmospheric Hg (TAM).
Collapse
Affiliation(s)
- Matthieu B Miller
- Department of Environmental Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW 2113, Australia.
| | - Dean A Howard
- Institute of Arctic and Alpine Research, University of Colorado Boulder, Boulder, CO 80303, United States
| | - Ashley M Pierce
- Department of Environmental Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW 2113, Australia
| | - Kellie R Cook
- Department of Environmental Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW 2113, Australia
| | - Melita Keywood
- Centre for Australian Climate and Weather Research, Australian Commonwealth Scientific and Industrial Research Organization, Melbourne, VIC, Australia
| | - Jennifer Powell
- Centre for Australian Climate and Weather Research, Australian Commonwealth Scientific and Industrial Research Organization, Melbourne, VIC, Australia
| | - Mae S Gustin
- Department of Natural Resources and Environmental Sciences, University of Nevada, Reno, NV 89557, United States
| | - Grant C Edwards
- Department of Environmental Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW 2113, Australia
| |
Collapse
|
15
|
Abstract
This review focuses on providing the history of measurement efforts to quantify and characterize the compounds of reactive mercury (RM), and the current status of measurement methods and knowledge. RM collectively represents gaseous oxidized mercury (GOM) and that bound to particles. The presence of RM was first recognized through measurement of coal-fired power plant emissions. Once discovered, researchers focused on developing methods for measuring RM in ambient air. First, tubular KCl-coated denuders were used for stack gas measurements, followed by mist chambers and annular denuders for ambient air measurements. For ~15 years, thermal desorption of an annular KCl denuder in the Tekran® speciation system was thought to be the gold standard for ambient GOM measurements. Research over the past ~10 years has shown that the KCl denuder does not collect GOM compounds with equal efficiency, and there are interferences with collection. Using a membrane-based system and an automated system—the Detector for Oxidized mercury System (DOHGS)—concentrations measured with the KCl denuder in the Tekran speciation system underestimate GOM concentrations by 1.3 to 13 times. Using nylon membranes it has been demonstrated that GOM/RM chemistry varies across space and time, and that this depends on the oxidant chemistry of the air. Future work should focus on development of better surfaces for collecting GOM/RM compounds, analytical methods to characterize GOM/RM chemistry, and high-resolution, calibrated measurement systems.
Collapse
|
16
|
Lyman SN, Gratz LE, Dunham-Cheatham SM, Gustin MS, Luippold A. Improvements to the Accuracy of Atmospheric Oxidized Mercury Measurements. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:13379-13388. [PMID: 33075225 DOI: 10.1021/acs.est.0c02747] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We developed a cation-exchange membrane-based dual-channel system to measure elemental and oxidized mercury and deployed it with an automated calibration system and the University of Nevada, Reno-Reactive Mercury Active System (UNR-RMAS) at a rural/suburban field site in Colorado during the summer of 2018. Unlike oxidized mercury measurements collected via the widely used KCl denuder method, the dual-channel system was able to quantitatively recover HgCl2 and HgBr2 injected by the calibrator into the ambient sample air and compared well with the UNR-RMAS measurements. The system measured at 10 min intervals and had a 3-h average detection limit for oxidized mercury of 33 pg m-3. It was able to detect day-to-day variability and diel cycles in oxidized mercury (0 to 200 pg m-3) and will be an important tool for future studies of atmospheric mercury. We used a gravimetric method to independently determine the total mercury permeation rate from the permeation tubes. Permeation rates derived from the gravimetric method matched the permeation rates observed via mercury measurement devices to within 25% when the mercury permeation rate was relatively high (up to 30 pg s-1), but the agreement decreased for lower permeation rates, probably because of increased uncertainty in the gravimetric measurements.
Collapse
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 84322-0305, United States
| | - Lynne E Gratz
- Environmental Studies Program, Colorado College, Colorado Springs, Colorado 80903-3298, United States
| | - Sarrah M Dunham-Cheatham
- Department of Natural Resources and Environmental Science, University of Nevada-Reno, Reno, Nevada 89557, United States
| | - Mae Sexauer Gustin
- Department of Natural Resources and Environmental Science, University of Nevada-Reno, Reno, Nevada 89557, United States
| | - Adriel Luippold
- Department of Natural Resources and Environmental Science, University of Nevada-Reno, Reno, Nevada 89557, United States
| |
Collapse
|
17
|
Gustin MS, Bank MS, Bishop K, Bowman K, Branfireun B, Chételat J, Eckley CS, Hammerschmidt CR, Lamborg C, Lyman S, Martínez-Cortizas A, Sommar J, Tsui MTK, Zhang T. Mercury biogeochemical cycling: A synthesis of recent scientific advances. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 737:139619. [PMID: 32783819 PMCID: PMC7430064 DOI: 10.1016/j.scitotenv.2020.139619] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 05/20/2020] [Indexed: 05/23/2023]
Abstract
The focus of this paper is to briefly discuss the major advances in scientific thinking regarding: a) processes governing the fate and transport of mercury in the environment; b) advances in measurement methods; and c) how these advances in knowledge fit in within the context of the Minamata Convention on Mercury. Details regarding the information summarized here can be found in the papers associated with this Virtual Special Issue of STOTEN.
Collapse
Affiliation(s)
- Mae Sexauer Gustin
- Department of Natural Resources and Environmental Science, University of Nevada, Reno, NV 89439, USA.
| | - Michael S Bank
- Department of Contaminants and Biohazards, Institute of Marine Research, Bergen, Norway; Department of Environmental Conservation, University of Massachusetts, Amherst, MA 01255, USA
| | - Kevin Bishop
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Box 7050, 75007 Uppsala, Sweden
| | - Katlin 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
| | - Brian Branfireun
- Department of Biology and Centre for Environment and Sustainability, Western University, London, Canada
| | - John Chételat
- Environment and Climate Change Canada, National Wildlife Research Centre, 1125 Colonel By Drive, Ottawa, ON K1A 0H3, Canada
| | - Chris S Eckley
- U.S. Environmental Protection Agency, Region-10, 1200 6th Ave, Seattle, WA 98101, USA
| | - Chad R Hammerschmidt
- Wright State University, Department of Earth and Environmental Sciences, 3640 Colonel Glenn Highway, Dayton, OH 45435, USA
| | - Carl Lamborg
- University of California Santa Cruz, Ocean Sciences Department, 1156 High Street, Santa Cruz, CA 95064, USA
| | - Seth Lyman
- Bingham Research Center, Utah State University, 320 N Aggie Blvd., Vernal, UT, USA
| | - Antonio Martínez-Cortizas
- EcoPast (GI-1553), Facultade de Bioloxía, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Jonas Sommar
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Martin Tsz-Ki Tsui
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27402, USA
| | - Tong Zhang
- College of Environmental Science and Engineering, Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, Nankai University, Tianjin 300350, China
| |
Collapse
|
18
|
Luippold A, Gustin MS, Dunham-Cheatham SM, Castro M, Luke W, Lyman S, Zhang L. Use of Multiple Lines of Evidence to Understand Reactive Mercury Concentrations and Chemistry in Hawai'i, Nevada, Maryland, and Utah, USA. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:7922-7931. [PMID: 32506903 DOI: 10.1021/acs.est.0c02283] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
To advance our understanding of the mercury (Hg) biogeochemical cycle, concentrations and chemistry of gaseous oxidized Hg (GOM), particulate-bound Hg (PBM), and reactive Hg (RM = GOM + PBM) need to be known. The UNR-RMAS 2.0 provides a solution that will advance knowledge. From 11/2017 to 02/2019, the RMAS 2.0 was deployed in Hawai'i, Nevada, Maryland, and Utah to test system performance and develop an understanding of RM at locations impacted by different atmospheric oxidants. Mauna Loa Observatory, Hawai'i, impacted by the free troposphere and the marine boundary layer, had primarily -Br/Cl RM compounds. The Nevada location, directly adjacent to a major interstate highway and experiences inputs from the free troposphere, exhibited -Br/Cl, -N, -S, and organic compounds. In Maryland, compounds observed were -N, -S, and organic-Hg. This site is downwind of coal-fired power plants and located in a forested area. The location in Utah is in a basin impacted by oil and natural gas extraction, multiday wintertime inversion episodes, and inputs from the free troposphere. Compounds were -Br/Cl or -O, -N, and -Br/Cl. The chemical forms of RM identified were consistent with the air source areas, predominant ion chemistry, criterion air pollutants, and meteorology.
Collapse
Affiliation(s)
- Adriel Luippold
- Department of Natural Resources and Environmental Science, University of Nevada, Reno, Nevada 89557, United States
| | - Mae Sexauer Gustin
- Department of Natural Resources and Environmental Science, University of Nevada, Reno, Nevada 89557, United States
| | - Sarrah M Dunham-Cheatham
- Department of Natural Resources and Environmental Science, University of Nevada, Reno, Nevada 89557, United States
| | - Mark Castro
- Appalachian Laboratory, University of Maryland Center for Environmental Science, Frostburg, Maryland 21532, United States
| | - Winston Luke
- Air Resources Laboratory, National Oceanic and Atmospheric Administration, College Park, Maryland 20740, United States
| | - Seth Lyman
- Bingham Research Center, Utah State University, Vernal, Utah 84322, United States
| | - Lei Zhang
- School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| |
Collapse
|
19
|
Sommar J, Osterwalder S, Zhu W. Recent advances in understanding and measurement of Hg in the environment: Surface-atmosphere exchange of gaseous elemental mercury (Hg 0). THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 721:137648. [PMID: 32182462 DOI: 10.1016/j.scitotenv.2020.137648] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 02/26/2020] [Accepted: 02/28/2020] [Indexed: 05/26/2023]
Abstract
The atmosphere is the major transport pathway for distribution of mercury (Hg) globally. Gaseous elemental mercury (GEM, hereafter Hg0) is the predominant form in both anthropogenic and natural emissions. Evaluation of the efficacy of reductions in emissions set by the UN's Minamata Convention (UN-MC) is critically dependent on the knowledge of the dynamics of the global Hg cycle. Of these dynamics including e.g. red-ox reactions, methylation-demethylation and dry-wet deposition, poorly constrained atmosphere-surface Hg0 fluxes especially limit predictability of the timescales of its global biogeochemical cycle. This review focuses on Hg0 flux field observational studies, namely the theory, applications, strengths, and limitations of the various experimental methodologies applied to gauge the exchange flux and decipher active sub-processes. We present an in-depth review, a comprehensive literature synthesis, and methodological and instrumentation advances for terrestrial and marine Hg0 flux studies in recent years. In particular, we outline the theory of a wide range of measurement techniques and detail the operational protocols. Today, the most frequently used measurement techniques to determine the net Hg0 flux (>95% of the published flux data) are dynamic flux chambers for small-scale and micrometeorological approaches for large-scale measurements. Furthermore, top-down approaches based on Hg0 concentration measurements have been applied as tools to better constrain Hg emissions as an independent way to e.g. challenge emission inventories. This review is an up-dated, thoroughly revised edition of Sommar et al. 2013 (DOI: 10.1080/10643389.2012.671733). To the tabulation of >100 cited flux studies 1988-2009 given in the former publication, we have here listed corresponding studies published during the last decade with a few exceptions (2008-2019). During that decade, Hg stable isotope ratios of samples involved in atmosphere-terrestrial interaction is at hand and provide in combination with concentration and/or flux measurements novel constraints to quantitatively and qualitatively assess the bi-directional Hg0 flux. Recent efforts in the development of relaxed eddy accumulation and eddy covariance Hg0 flux methods bear the potential to facilitate long-term, ecosystem-scale flux measurements to reduce the prevailing large uncertainties in Hg0 flux estimates. Standardization of methods for Hg0 flux measurements is crucial to investigate how land-use change and how climate warming impact ecosystem-specific Hg0 sink-source characteristics and to validate frequently applied model parameterizations describing the regional and global scale Hg cycle.
Collapse
Affiliation(s)
- Jonas Sommar
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, China.
| | - Stefan Osterwalder
- Institut des Géosciences de l'Environnement, Université Grenoble Alpes, CNRS, IRD, Grenoble INP, Grenoble, France
| | - Wei Zhu
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| |
Collapse
|
20
|
Bishop K, Shanley JB, Riscassi A, de Wit HA, Eklöf K, Meng B, Mitchell C, Osterwalder S, Schuster PF, Webster J, Zhu W. Recent advances in understanding and measurement of mercury in the environment: Terrestrial Hg cycling. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 721:137647. [PMID: 32197286 DOI: 10.1016/j.scitotenv.2020.137647] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 02/23/2020] [Accepted: 02/28/2020] [Indexed: 06/10/2023]
Abstract
This review documents recent advances in terrestrial mercury cycling. Terrestrial mercury (Hg) research has matured in some areas, and is developing rapidly in others. We summarize the state of the science circa 2010 as a starting point, and then present the advances during the last decade in three areas: land use, sulfate deposition, and climate change. The advances are presented in the framework of three Hg "gateways" to the terrestrial environment: inputs from the atmosphere, uptake in food, and runoff with surface water. Among the most notable advances: These and other advances reported here are of value in evaluating the effectiveness of the Minamata Convention on reducing environmental Hg exposure to humans and wildlife.
Collapse
Affiliation(s)
- Kevin Bishop
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Box 7050, 75007 Uppsala, Sweden.
| | | | - Ami Riscassi
- Department of Environmental Sciences, University of Virginia, P.O. Box 400123, Charlottesville, VA 22904-4123, USA.
| | - Heleen A de Wit
- Norwegian Institute for Water Research, Gaustadalléen 21, NO-0349, Norway.
| | - Karin Eklöf
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Box 7050, 75007 Uppsala, Sweden.
| | - Bo Meng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China.
| | - Carl Mitchell
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada.
| | - Stefan Osterwalder
- Institut des Géosciences de l'Environnement, Université Grenoble Alpes, CNRS, IRD, Grenoble 18 INP, 38000 Grenoble, France.
| | - Paul F Schuster
- U.S. Geological Survey, 3215 Marine Street, Suite E-127, Boulder, CO 80303-1066, USA.
| | - Jackson Webster
- Department of Civil Engineering, California State University, 400 W. 1st Street, 21 95929-0930 Chico, CA, USA.
| | - Wei Zhu
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, 90183 Umeå, Sweden.
| |
Collapse
|
21
|
Tang H, You W, Wang Z, Li C, Zhu C, Cai L, Duan Y. Detrimental effects of SO 2 on gaseous mercury(II) adsorption and retention by CaO-based sorbent traps: Competition and heterogeneous reduction. JOURNAL OF HAZARDOUS MATERIALS 2020; 387:121679. [PMID: 31796365 DOI: 10.1016/j.jhazmat.2019.121679] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 10/15/2019] [Accepted: 11/11/2019] [Indexed: 06/10/2023]
Abstract
Reliable gaseous Hg(II) measurement is crucial to mercury emissions control from coal-fired flue gas, but Hg(II) sampling under SO2 condition could probably increase the uncertainty of sorbent traps. CaO-AcS synthesized from calcium acetate and porous support were previously demonstrated to be effective for Hg(II) trapping under SO2-free condition. This work further evaluated SO2 influence on its Hg(II) retention ability via integrating experimental and DFT computational studies. Increased breakthrough rate of HgCl2 was found in a two-section CaO-AcS trap under SO2 conditions. Significant basicity and porosity loss of CaO-AcS were attributed to the formation of agglomerate CaSO3. Hg0 release from CaO-AcS samples suggested potential reactions between Hg(II) and SO2. The detected HgO and Hg2SO4 species by Hg-TPD in CaO-AcS further confirmed this speculation. Moreover, both competition and reduction effects of SO2 on surface-bound Hg(II) species were substantiated by DFT calculations. SO2 showed a stronger interaction with CaO than HgCl2 because SO2 has a lower LUMO level and can accept electrons easier. Reaction pathways indicated Hg(II) was partially reduced to Hg2SO4 under SO2-deficient condition, or directly reduced to Hg0 under SO2-rich condition. This work fully proposed the SO2 influence mechanisms and improvement countermeasures for practical gaseous Hg(II) sampling.
Collapse
Affiliation(s)
- Hongjian Tang
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu, 210096, China; Department of Chemical and Biomolecular Engineering, National University of Singapore, 117576, Singapore
| | - Wenqin You
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia, 30332, United States
| | - Zewei Wang
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia, 30332, United States
| | - Chunfeng Li
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu, 210096, China
| | - Chun Zhu
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu, 210096, China
| | - Liang Cai
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu, 210096, China
| | - Yufeng Duan
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu, 210096, China.
| |
Collapse
|
22
|
Lyman SN, Cheng I, Gratz LE, Weiss-Penzias P, Zhang L. An updated review of atmospheric mercury. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 707:135575. [PMID: 31784172 DOI: 10.1016/j.scitotenv.2019.135575] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 11/14/2019] [Accepted: 11/15/2019] [Indexed: 06/10/2023]
Abstract
The atmosphere is a key component of the biogeochemical cycle of mercury, acting as a reservoir, transport mechanism, and facilitator of chemical reactions. The chemical and physical behavior of atmospheric mercury determines how, when, and where emitted mercury pollution impacts ecosystems. In this review, we provide current information about what is known and what remains uncertain regarding mercury in the atmosphere. We discuss new ambient, laboratory, and theoretical information about the chemistry of mercury in various atmospheric media. We review what is known about mercury in and on solid- and liquid-phase aerosols. We present recent findings related to wet and dry deposition and spatial and temporal trends in atmospheric mercury concentrations. We also review atmospheric measurement methods that are in wide use and those that are currently under development.
Collapse
Affiliation(s)
- Seth N Lyman
- Bingham Research Center, Utah State University, 320 N Aggie Blvd., Vernal, UT, USA; Department of Chemistry and Biochemistry, Utah State University, 4820 Old Main Hill, Logan, UT, USA.
| | - Irene Cheng
- Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin St., Toronto, Ontario, Canada
| | - Lynne E Gratz
- Environmental Studies Program, Colorado College, 14 East Cache la Poudre St., Colorado Springs, CO, USA
| | - Peter Weiss-Penzias
- Chemistry and Biochemistry Department, University of California, Santa Cruz, 1156 High St, Santa Cruz, CA, USA; Microbiology and Environmental Toxicology Department, University of California, Santa Cruz, 1156 High St, Santa Cruz, CA, USA
| | - Leiming Zhang
- Air Quality Research Division, Environment and Climate Change Canada, 4905 Dufferin St., Toronto, Ontario, Canada
| |
Collapse
|
23
|
Development of methodology to generate, measure, and characterize the chemical composition of oxidized mercury nanoparticles. Anal Bioanal Chem 2019; 412:691-702. [PMID: 31853601 DOI: 10.1007/s00216-019-02279-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 11/09/2019] [Accepted: 11/12/2019] [Indexed: 10/25/2022]
Abstract
The phase of oxidized mercury is critical in the fate, transformation, and bioavailability of mercury species in Earth's ecosystem. There is now evidence that what is measured as gaseous oxidized mercury (GOM) is not only gaseous but also consists of airborne nanoparticles with distinct physicochemical properties. Herein, we present the development of the first method for the consistent and reproducible generation of oxidized mercury nano- and sub-micron particles (~ 5 to 400 nm). Oxidized mercury nanoparticles are generated using two methods, vapor-phase condensation and aqueous nebulization, for three proxies: mercury(II) bromide (HgBr2), mercury(II) chloride (HgCl2), and mercury(II) oxide (HgO). These aerosols are characterized using scanning mobility and optical sizing, high-resolution scanning transmission electron microscopy (STEM), and nano/microparticle interface coupled to soft ionization mercury mass spectrometric techniques. Synthetic nanoparticle stability was studied in aqueous media, and using a microcosm at ambient tropospheric conditions of ~ 740 Torr pressure, room temperature, and at relative humidity of approximately 20%. Analysis of microcosm airborne nanoparticles confirmed that generated synthetic mercury nanoparticles retain their physical properties once in air. KCl-coated denuders, which are currently used globally to measure gaseous mercury compounds, were exposed to generated oxidized mercury nanoparticles. The degree of synthetic mercury nanoparticle capture by KCl-coated denuders and particulate filters was assessed. A significant portion of nanoparticulate and sub-micron particulate mercury was trapped on the KCl-coated denuder and measured as GOM. Finally, we demonstrate the applicability of soft ionization mercury mass spectrometry to the measurement of mercury species present in the gaseous and solid phase. We recommend coupling of this technique with existing methodology for a more accurate representation of mercury biogeochemistry cycling. Graphical Abstract.
Collapse
|
24
|
Gustin MS, Dunham-Cheatham SM, Zhang L. Comparison of 4 Methods for Measurement of Reactive, Gaseous Oxidized, and Particulate Bound Mercury. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:14489-14495. [PMID: 31742397 DOI: 10.1021/acs.est.9b04648] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The atmosphere is an important (1) pathway by which mercury (Hg) is transported around the globe and (2) source of Hg to ecosystems. Thus, understanding Hg atmospheric chemistry is critical for understanding the biogeochemical cycle and impacts to human and ecosystem health. Work over the past 13 years has demonstrated that the standard instrument used to measure atmospheric Hg does not accurately quantify gaseous oxidized mercury (GOM) or particulate bound mercury (PBM). This study focused on comparing four methods for quantifying atmospheric Hg and identifying Hg(II) compounds. Data from two automated systems, the Tekran 2537/1130 system and the University of Nevada, Reno-Dual Channel System (DCS), were compared with two University of Nevada, Reno-Reactive Mercury Active Systems (RMAS 2.0). One RMAS 2.0 included cation exchange membranes (CEMs) and nylon membranes, and the second included a polytetrafluoroethylene (PTFE) membrane upstream of the CEM and nylon membranes. The Tekran system and the DCS underestimated GOM concentrations with respect to that measured using the RMAS 2.0. The RMAS 2.0 with the upstream PTFE provided a means of distinguishing GOM and PBM. Thermal desorption of nylon membrane data identified a variety of GOM and PBM compounds present.
Collapse
Affiliation(s)
- 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
| | - Lei Zhang
- School of the Environment , Nanjing University , Nanjing , Jiangsu 210023 , China
| |
Collapse
|
25
|
Phu Nguyen LS, Zhang L, Lin DW, Lin NH, Sheu GR. Eight-year dry deposition of atmospheric mercury to a tropical high mountain background site downwind of the East Asian continent. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 255:113128. [PMID: 31521990 DOI: 10.1016/j.envpol.2019.113128] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 07/27/2019] [Accepted: 08/27/2019] [Indexed: 06/10/2023]
Abstract
Atmospheric deposition, either dry or wet, has been identified as an important pathway of mercury (Hg) input to terrestrial and aquatic systems. Although East Asia is the major atmospheric Hg emission source region, very few studies have been conducted to quantify atmospheric Hg deposition in its downwind region. In this study, 8-year (2009-2016) atmospheric Hg dry deposition was reported at the Lulin Atmospheric Background Station (LABS), a high mountain forest site in central Taiwan. Dry deposition of speciated Hg was estimated using a bi-directional air-surface flux exchange model for gaseous elemental mercury (GEM) and dry deposition models for gaseous oxidized mercury (GOM) and particulate-bound mercury (PBM), making use of the monitored speciated atmospheric Hg concentrations. Annual total Hg dry deposition ranged from 51.9 to 84.9 μg m-2 yr-1, with a multi-year average of 66.1 μg m-2 yr-1. Among the three forms of atmospheric Hg, GEM was the main contributor to the total dry deposition, contributing about 77.8% to the total, due to the high density of forest canopy as well as the much higher concentration of GEM than GOM and PBM at LABS. Mercury dry deposition is higher in winter and spring than in summer and fall, partly due to the elevated Hg concentrations associated with air masses from East and Southeast Asia where with high atmospheric Hg emissions. The mean annual dry/wet deposition ratio of 2.8 at LABS indicated that Hg deposition to forest landscape was governed by dry rather than wet deposition.
Collapse
Affiliation(s)
- Ly Sy Phu Nguyen
- Department of Atmospheric Sciences, National Central University, Jhongli, 320, Taiwan
| | - Leiming Zhang
- Environment and Climate Change Canada, Toronto, Ontario, Canada
| | - Da-Wei Lin
- Department of Atmospheric Sciences, National Central University, Jhongli, 320, Taiwan
| | - Neng-Huei Lin
- Department of Atmospheric Sciences, National Central University, Jhongli, 320, Taiwan
| | - Guey-Rong Sheu
- Department of Atmospheric Sciences, National Central University, Jhongli, 320, Taiwan.
| |
Collapse
|
26
|
Nguyen LSP, Sheu GR, Lin DW, Lin NH. Temporal changes in atmospheric mercury concentrations at a background mountain site downwind of the East Asia continent in 2006-2016. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 686:1049-1056. [PMID: 31200303 DOI: 10.1016/j.scitotenv.2019.05.425] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/06/2019] [Accepted: 05/28/2019] [Indexed: 06/09/2023]
Abstract
Atmospheric mercury (Hg) has been monitored at the Lulin Atmospheric Background Station (LABS) in Taiwan since April 2006 and is still continuing. Here we reported the trend in gaseous elemental Hg (GEM) concentrations at LABS between April 2006 and December 2016, before the Minamata Convention on Mercury entered into force in 2017. Previous research indicated nighttime (0-8 am) data collected at LABS are better representative of regional influence. Therefore, only nighttime GEM data were used for trend analysis. A significant decreasing trend in GEM at a rate of -1.5% yr-1 (-0.022 ng m-3 yr-1, p < 0.01) was found, comparable to the decreasing trends observed in Europe, North America, South Africa, and over the North Atlantic Ocean. Five major GEM source regions to the LABS were identified, including northern Indochina Peninsula, China, Northeast Asia, the Pacific Ocean, and South China Sea. Significant decreasing trends in GEM were found for air masses coming from northern Indochina Peninsula (-0.042 ng m-3 yr-1, -2.6% yr-1, p < 0.01), China (-0.041 ng m-3 yr-1, -2.4% yr-1, p < 0.01), Northeast Asia (-0.031 ng m-3 yr-1, -2.0% yr-1, p < 0.05), and the Pacific Ocean (-0.022 ng m-3 yr-1, -1.7% yr-1, p < 0.05). Decreasing GEM trend (-0.020 ng m-3 yr-1, -1.5% yr-1), but insignificant (p > 0.05), was also found for air masses coming from South China Sea. The decreasing trends observed with air from the Pacific Ocean and South China Sea indicated declining background GEM concentrations in Northern Hemisphere. Decrease in GEM concentrations at the LABS was in agreement with the reduction in atmospheric Hg export from the East Asia continent caused by changes in Hg emission quantity and speciation, and temporal and spatial distribution in emission sources that have been suggested by recent research. Additionally, changes in the frequency distribution of air mass origins and transport paths may also contribute to the changes in GEM concentrations at LABS.
Collapse
Affiliation(s)
- Ly Sy Phu Nguyen
- Department of Atmospheric Sciences, National Central University, Jhongli 320, Taiwan
| | - Guey-Rong Sheu
- Department of Atmospheric Sciences, National Central University, Jhongli 320, Taiwan.
| | - Da-Wei Lin
- Department of Atmospheric Sciences, National Central University, Jhongli 320, Taiwan
| | - Neng-Huei Lin
- Department of Atmospheric Sciences, National Central University, Jhongli 320, Taiwan
| |
Collapse
|
27
|
Ghoshdastidar AJ, Ariya PA. The Existence of Airborne Mercury Nanoparticles. Sci Rep 2019; 9:10733. [PMID: 31341248 PMCID: PMC6656720 DOI: 10.1038/s41598-019-47086-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 07/05/2019] [Indexed: 11/30/2022] Open
Abstract
Mercury is an important global toxic contaminant of concern that causes cognitive and neuromuscular damage in humans. It is ubiquitous in the environment and can travel in the air, in water, or adsorb to soils, snow, ice and sediment. Two significant factors that influence the fate of atmospheric mercury, its introduction to aquatic and terrestrial environments, and its bioaccumulation and biomagnification in biotic systems are the chemical species or forms that mercury exists as (elemental, oxidized or organic) and its physical phase (solid, liquid/aqueous, or gaseous). In this work, we show that previously unknown mercury-containing nanoparticles exist in the air using high-resolution scanning transmission electron microscopy imaging (HR-STEM). Deploying an urban-air field campaign near a mercury point source, we provide further evidence for mercury nanoparticles and determine the extent to which these particles contain two long suspected forms of oxidized mercury (mercuric bromide and mercuric chloride) using mercury mass spectrometry (Hg-MS). Using optical particle sizers, we also conclude that the conventional method of measuring gaseous oxidized mercury worldwide can trap up to 95% of nanoparticulate mercuric halides leading to erroneous measurements. Finally, we estimate airborne mercury aerosols may contribute to half of the oxidized mercury measured in wintertime Montréal urban air using Hg-MS. These emerging mercury-containing nanoparticle contaminants will influence mercury deposition, speciation and other atmospheric and aquatic biogeochemical mercury processes including the bioavailability of oxidized mercury to biota and its transformation to neurotoxic organic mercury.
Collapse
Affiliation(s)
- Avik J Ghoshdastidar
- Department of Chemistry, McGill University, 801 Sherbrooke St. W., Montreal, QC, H3A 2K6, Canada
| | - Parisa A Ariya
- Department of Chemistry, McGill University, 801 Sherbrooke St. W., Montreal, QC, H3A 2K6, Canada.
- Department of Atmospheric and Oceanic Sciences, McGill University, 805 Sherbrooke St. W., Montreal, QC, H3A 0B9, Canada.
| |
Collapse
|
28
|
Tang H, Li C, Duan Y, Zhu C, Cai L. Combined experimental and theoretical studies on adsorption mechanisms of gaseous mercury(II) by calcium-based sorbents: The effect of unsaturated oxygen sites. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 656:937-945. [PMID: 30625679 DOI: 10.1016/j.scitotenv.2018.11.460] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 11/24/2018] [Accepted: 11/30/2018] [Indexed: 06/09/2023]
Abstract
Accurate mercury speciation measurements are critical for developing methods for mercury removal from flue gas, but the lack of reliable adsorbents has made Hg2+ selective retention challenging. Calcium oxide (CaO) loaded on porous support is promising for HgCl2 selective adsorption because of its porosity and alkaline nature. The main hypothesis investigated in this paper is if the capacity of CaO sorbent for HgCl2 selective adsorption is attributed to its basic sites, then this will be drastically impacted by the calcium precursors. We synthesized a suite of CaO/SiO2 sorbents from different precursors, including hydrated calcium oxide (CaO-HS), calcium nitrate tetrahydrate (CaO-NS), and calcium acetate monohydrate (CaO-AcS), to investigate their performance on HgCl2 selective adsorption in a fixed-bed reactor. Compared with CaO-HS and CaO-NS, CaO-AcS was demonstrated to have the strongest affinity for HgCl2 and almost complete breakthrough for Hg0. Advanced porosity and surface basicity of CaO-AcS were confirmed by characterization analysis. CaO (001) and CaO (011) facet as well as surface defects that have different unsaturated O sites were observed using the high resolution transmission electron microscope (HRTEM). Combined theoretical and experimental methods were used to study the interaction mechanisms between HgCl2 and basic sites on CaO-AcS surfaces. Density functional theory (DFT) calculations indicated all CaO surfaces weakly interact with Hg0, while four robust bonding states of HgCl2 were predicted on different basic sites with the intensity in increasing order: Monodentate < Tridendate < Bidentate < Bridging. This was consistent with HgCl2-TPD experiments that demonstrated that the four HgCl2 adsorption configurations on CaO-AcS were attributed to different unsaturated O sites. The findings in this work highlight the application potential of CaO-AcS for gaseous Hg2+ sampling and measurement from coal-fired flue gas.
Collapse
Affiliation(s)
- Hongjian Tang
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu 210096, China
| | - Chunfeng Li
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu 210096, China
| | - Yufeng Duan
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu 210096, China.
| | - Chun Zhu
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu 210096, China
| | - Liang Cai
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu 210096, China
| |
Collapse
|
29
|
Zhou H, Hopke PK, Zhou C, Holsen TM. Ambient mercury source identification at a New York State urban site: Rochester, NY. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 650:1327-1337. [PMID: 30308819 DOI: 10.1016/j.scitotenv.2018.09.040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 08/10/2018] [Accepted: 09/03/2018] [Indexed: 06/08/2023]
Abstract
Gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM), and particle-bound mercury (PBM) were measured continuously in Rochester, NY (NY43) from January 2012 to December 2014. Continuous measurements of ozone (O3), sulfur dioxide (SO2), carbon monoxide (CO), nitrogen oxide (NO), nitrogen dioxide (NO2), particulate matter (PM2.5), and meteorological data were also made at this site. A principal component analysis (PCA) of the resulting 15 variables showed that the ambient mercury in Rochester was primarily produced by non-local sources in contrast to earlier studies that showed that local sources were present. Positive matrix factorization (PMF) analysis of the atmospheric mercury and other pollutant species concentrations showed that transport and atmospheric processes have become the major source of mercury in Rochester. Conditional bivariate probability function (CBPF) and potential source contribution function (PSCF) were used to identify local and distant mercury sources. The results in this study showed that the closure of a coal-fired power plant and promulgation of several fuel quality policies reduced local mercury emissions making long-distance transport the major source of mercury in Rochester.
Collapse
Affiliation(s)
- Hao Zhou
- Institute for a Sustainable Environment, Clarkson University, Potsdam, NY 13699, United States of America
| | - Philip K Hopke
- Institute for a Sustainable Environment, Clarkson University, Potsdam, NY 13699, United States of America; Department of Public Health Sciences, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, United States of America.
| | - Chuanlong Zhou
- Department of Civil and Environmental Engineering, Clarkson University, Potsdam, NY 13699, United States of America
| | - Thomas M Holsen
- Department of Civil and Environmental Engineering, Clarkson University, Potsdam, NY 13699, United States of America
| |
Collapse
|
30
|
Pierce AM, Gustin MS, Christensen JN, Loría-Salazar SM. Use of multiple tools including lead isotopes to decipher sources of ozone and reactive mercury to urban and rural locations in Nevada, USA. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 615:1411-1427. [PMID: 29751446 DOI: 10.1016/j.scitotenv.2017.08.284] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 08/22/2017] [Accepted: 08/28/2017] [Indexed: 06/08/2023]
Abstract
Ambient air particulate matter (<2.5μm in diameter) samples were collected on two different filter types in 2014 and 2015 over 24h periods and analyzed for reactive mercury (gaseous oxidized mercury+particulate bound mercury) concentrations and lead isotopes to determine sources of pollution to three sites in Nevada, USA. Two sites were located on the western edge of Nevada (Reno, urban, 1370m and Peavine Peak, rural, high elevation, 2515m); the third location was ~485km east in rural Great Basin National Park, NV (2061m). Reactive mercury samples were collected on cation exchange membranes simultaneously with lead samples, collected on Teflon membranes. Lead isotopic ratios have previously identified trans-Pacific lead sources based on the 206/207 and 208/207 lead ratios. Influence from trans-Pacific air masses was higher from March to June associated with long-range transport of pollutants. Spring months are well known for increased transport across the Pacific; however, fall months were also influenced by trans-Pacific air masses in this study. Western North American background ozone concentrations have been measured and modeled at 50 to 55ppbv. Median ozone concentrations at both rural sites in Nevada were within this range. Sources leading to enhancements in ozone of 2 to 18ppbv above monthly medians in Nevada included emissions from Eurasia, regional urban centers, and global and regional wildfires, resulting in concentrations close to the USA air quality standard. At the high elevation locations, ozone was derived from pollutants being transported in the free troposphere that originate around the globe; however, Eurasia and Asia were dominant sources to the Western USA. Negative correlations between reactive mercury and percent Asian lead, Northern Eurasia and East Asia trajectories indicated reactive mercury concentrations at the two high elevation sites were produced by oxidants from local, regional, and marine boundary layer sources.
Collapse
Affiliation(s)
- Ashley M Pierce
- Department of Natural Resources and Environmental Sciences, University of Nevada, Reno, NV 89557, USA.
| | - Mae Sexauer Gustin
- Department of Natural Resources and Environmental Sciences, University of Nevada, Reno, NV 89557, USA.
| | - John N Christensen
- Energy Geosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - S Marcela Loría-Salazar
- Atmospheric Science Program, Department of Physics, University of Nevada, Reno, NV 89557, USA
| |
Collapse
|
31
|
Marusczak N, Sonke JE, Fu X, Jiskra M. Tropospheric GOM at the Pic du Midi Observatory-Correcting Bias in Denuder Based Observations. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:863-869. [PMID: 27960251 DOI: 10.1021/acs.est.6b04999] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Gaseous elemental mercury (GEM, Hg) emissions are transformed to divalent reactive Hg (RM) forms throughout the troposphere and stratosphere. RM is often operationally quantified as the sum of particle bound Hg (PBM) and gaseous oxidized Hg (GOM). The measurement of GOM and PBM is challenging and under mounting criticism. Here we intercompare six months of automated GOM and PBM measurements using a Tekran (TK) KCl-coated denuder and quartz regenerable particulate filter method (GOMTK, PBMTK, and RMTK) with RMCEM collected on cation exchange membranes (CEMs) at the high altitude Pic du Midi Observatory. We find that RMTK is systematically lower by a factor of 1.3 than RMCEM. We observe a significant relationship between GOMTK (but not PBMTK) and Tekran flushTK blanks suggesting significant loss (36%) of labile GOMTK from the denuder or inlet. Adding the flushTK blank to RMTK results in good agreement with RMCEM (slope = 1.01, r2 = 0.90) suggesting we can correct bias in RMTK and GOMTK. We provide a bias corrected (*) Pic du Midi data set for 2012-2014 that shows GOM* and RM* levels in dry free tropospheric air of 198 ± 57 and 229 ± 58 pg m-3 which agree well with in-flight observed RM and with model based GOM and RM estimates.
Collapse
Affiliation(s)
- Nicolas Marusczak
- Observatoire Midi-Pyrénées, Laboratoire Géosciences Environnement Toulouse, CNRS/IRD/Université de Toulouse, 14, avenue Édouard Belin, 31400 Toulouse, France
| | - Jeroen E Sonke
- Observatoire Midi-Pyrénées, Laboratoire Géosciences Environnement Toulouse, CNRS/IRD/Université de Toulouse, 14, avenue Édouard Belin, 31400 Toulouse, France
| | - Xuewu Fu
- Observatoire Midi-Pyrénées, Laboratoire Géosciences Environnement Toulouse, CNRS/IRD/Université de Toulouse, 14, avenue Édouard Belin, 31400 Toulouse, France
| | - Martin Jiskra
- Observatoire Midi-Pyrénées, Laboratoire Géosciences Environnement Toulouse, CNRS/IRD/Université de Toulouse, 14, avenue Édouard Belin, 31400 Toulouse, France
| |
Collapse
|
32
|
Cheng I, Zhang L. Uncertainty Assessment of Gaseous Oxidized Mercury Measurements Collected by Atmospheric Mercury Network. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:855-862. [PMID: 28009168 DOI: 10.1021/acs.est.6b04926] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Gaseous oxidized mercury (GOM) measurement uncertainties undoubtedly impact the understanding of mercury biogeochemical cycling; however, there is a lack of consensus on the uncertainty magnitude. The numerical method presented in this study provides an alternative means of estimating the uncertainties of previous GOM measurements. Weekly GOM in ambient air was predicted from measured weekly mercury wet deposition using a scavenging ratio approach, and compared against field measurements of 2-4 hly GOM to estimate the measurement biases of the Tekran speciation instruments at 13 Atmospheric Mercury Network (AMNet) sites. Multiyear average GOM measurements were estimated to be biased low by more than a factor of 2 at six sites, between a factor of 1.5 and 1.8 at six other sites, and below a factor of 1.3 at one site. The differences between predicted and observed were significantly larger during summer than other seasons potentially because of higher ozone concentrations that may interfere with GOM sampling. The analysis data collected over six years at multiple sites suggests a systematic bias in GOM measurements, supporting the need for further investigation of measurement technologies and identifying the chemical composition of GOM.
Collapse
Affiliation(s)
- Irene Cheng
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4 Canada
| | - Leiming Zhang
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4 Canada
| |
Collapse
|
33
|
Pierce AM, Gustin MS. Development of a Particulate Mass Measurement System for Quantification of Ambient Reactive Mercury. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:436-445. [PMID: 27966905 DOI: 10.1021/acs.est.6b04707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The Teledyne Advanced Pollution Instrumentation (TAPI) model 602 BetaPlus particulate system provides nondestructive analysis of particulate matter (PM2.5) mass concentration. This instrument was used to determine if measurements made with cation exchange membranes (CEM) were comparable to standard methods, the β attenuation method at two locations in Reno, NV and an environmental β attenuation method and gravimetric method at Great Basin National Park, NV. TAPI PM2.5 CEM measurements were statistically similar to the other three PM2.5 methods. Once this was established, the second objective, a destructive method for measurement of reactive mercury (RM = gaseous oxidized and particulate bound Hg), was tested. Samples collected at 16.7 L per min (Lpm) for 24 h on CEM from the TAPI were compared to those measured by the University of Nevada, Reno-Reactive Mercury Active System (UNRRMAS, 1 Lpm) CEM and a Tekran 2537/1130/1135 system (7 Lpm). Given the use of CEM in the TAPI and UNRRMAS, we hypothesized that both should collect RM. Due to the high flow rate and different inlets, TAPI data were systematically lower than the UNRRMAS. Correlation between RM concentrations demonstrated that the TAPI may be used to estimate 24 h resolution RM concentrations in Nevada.
Collapse
Affiliation(s)
- Ashley M Pierce
- Department of Natural Resources and Environmental Sciences, University of Nevada , Reno, 1664 N. Virginia St. Reno, Nevada 89557, United States
| | - Mae Sexauer Gustin
- Department of Natural Resources and Environmental Sciences, University of Nevada , Reno, 1664 N. Virginia St. Reno, Nevada 89557, United States
| |
Collapse
|
34
|
Sexauer Gustin M, Pierce AM, Huang J, Miller MB, Holmes HA, Loria-Salazar SM. Evidence for Different Reactive Hg Sources and Chemical Compounds at Adjacent Valley and High Elevation Locations. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:12225-12231. [PMID: 27801579 DOI: 10.1021/acs.est.6b03339] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The spatial distribution of chemical compounds and concentration of reactive mercury (RM), defined as the sum of gaseous oxidized mercury (GOM) and <3 μm particulate bound mercury (PBM), are poorly characterized. The objective of this study was to understand the chemistry, concentration, and spatial and temporal distribution of GOM at adjacent locations (12 km apart) with a difference in elevation of ∼1000 m. Atmospheric GOM measurements were made with passive and active samplers using membranes, and at one location, a Tekran mercury measurement system was used. The chemistry of GOM varied across time and location. On the basis of data collected, chemistry at the low elevation site adjacent to a highway was primarily influenced by pollutants generated by mobile sources (GOM = nitrogen and sulfur-based compounds), and the high elevation site (GOM = halogen-based compounds) was affected by long-range transport in the free troposphere over the marine boundary layer into Nevada. Data collected at these two locations demonstrate that different GOM compounds exist depending on the oxidants present in the air. Measurements of GOM made by the KCl denuder in the Tekran instrument located at the low elevation site were lower than that measured using membranes by 1.7-13 times. Accurate measurements of atmospheric concentrations and chemistry of RM are necessary for proper assessment of environmental impacts, and field measurements are essential for atmospheric models, which in turn influence policy decisions.
Collapse
Affiliation(s)
- Mae Sexauer Gustin
- Department of Natural Resources and Environmental Science and ‡Atmospheric Sciences Program, Department of Physics University of Nevada-Reno , Reno, Nevada 89557, United States
| | - Ashley M Pierce
- Department of Natural Resources and Environmental Science and ‡Atmospheric Sciences Program, Department of Physics University of Nevada-Reno , Reno, Nevada 89557, United States
| | - Jiaoyan Huang
- Department of Natural Resources and Environmental Science and ‡Atmospheric Sciences Program, Department of Physics University of Nevada-Reno , Reno, Nevada 89557, United States
| | - Matthieu B Miller
- Department of Natural Resources and Environmental Science and ‡Atmospheric Sciences Program, Department of Physics University of Nevada-Reno , Reno, Nevada 89557, United States
| | - Heather A Holmes
- Department of Natural Resources and Environmental Science and ‡Atmospheric Sciences Program, Department of Physics University of Nevada-Reno , Reno, Nevada 89557, United States
| | - S Marcela Loria-Salazar
- Department of Natural Resources and Environmental Science and ‡Atmospheric Sciences Program, Department of Physics University of Nevada-Reno , Reno, Nevada 89557, United States
| |
Collapse
|
35
|
Fu X, Marusczak N, Wang X, Gheusi F, Sonke JE. Isotopic Composition of Gaseous Elemental Mercury in the Free Troposphere of the Pic du Midi Observatory, France. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:5641-5650. [PMID: 27214126 DOI: 10.1021/acs.est.6b00033] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Understanding the sources and transformations of mercury (Hg) in the free troposphere is a critical aspect of global Hg research. Here we present one year of observations of atmospheric Hg speciation and gaseous elemental Hg (GEM) isotopic composition at the high-altitude Pic du Midi Observatory (2860 m above sea level) in France. Biweekly integrated GEM from February 2012 to January 2013 revealed significant variations in δ(202)HgGEM (-0.04‰ to 0.52‰) but not in Δ(199)HgGEM (-0.17‰ to -0.27‰) or Δ(200)HgGEM (-0.10‰ to 0.05‰). δ(202)HgGEM was negatively correlated with CO and reflected air mass origins from Europe (high CO, low δ(202)HgGEM) and from the Atlantic Ocean (low CO, high δ(202)HgGEM). We suggest that the δ(202)HgGEM variations represent mixing of recent low δ(202)HgGEM European anthropogenic emissions with high δ(202)HgGEM northern hemispheric background GEM. In addition, Atlantic Ocean free troposphere air masses showed a positive correlation between δ(202)HgGEM and gaseous oxidized Hg (GOM) concentrations, indicative of mass-dependent Hg isotope fractionation during GEM oxidation. On the basis of atmospheric δ(202)HgGEM and speciated Hg observations, we suggest that the oceanic free troposphere is a reservoir within which GEM is readily oxidized to GOM.
Collapse
Affiliation(s)
- Xuewu Fu
- Observatoire Midi-Pyrénées, Laboratoire Géosciences Environnement Toulouse, CNRS/IRD/Université de Toulouse, 14, avenue Édouard Belin, 31400 Toulouse, France
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences , 46 Guanshui Road 550002, Guiyang, China
| | - Nicolas Marusczak
- Observatoire Midi-Pyrénées, Laboratoire Géosciences Environnement Toulouse, CNRS/IRD/Université de Toulouse, 14, avenue Édouard Belin, 31400 Toulouse, France
| | - Xun Wang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences , 46 Guanshui Road 550002, Guiyang, China
| | - François Gheusi
- Observatoire Midi-Pyrénées, Laboratoire d'Aérologie, CNRS/IRD/Université de Toulouse, 14, avenue Édouard Belin, 31400 Toulouse, France
| | - Jeroen E Sonke
- Observatoire Midi-Pyrénées, Laboratoire Géosciences Environnement Toulouse, CNRS/IRD/Université de Toulouse, 14, avenue Édouard Belin, 31400 Toulouse, France
| |
Collapse
|
36
|
Enrico M, Roux GL, Marusczak N, Heimbürger LE, Claustres A, Fu X, Sun R, Sonke JE. Atmospheric Mercury Transfer to Peat Bogs Dominated by Gaseous Elemental Mercury Dry Deposition. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:2405-12. [PMID: 26849121 DOI: 10.1021/acs.est.5b06058] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Gaseous elemental mercury (GEM) is the dominant form of mercury in the atmosphere. Its conversion into oxidized gaseous and particulate forms is thought to drive atmospheric mercury wet deposition to terrestrial and aquatic ecosystems, where it can be subsequently transformed into toxic methylmercury. The contribution of mercury dry deposition is however largely unconstrained. Here we examine mercury mass balance and mercury stable isotope composition in a peat bog ecosystem. We find that isotope signatures of living sphagnum moss (Δ(199)Hg = -0.11 ± 0.09‰, Δ(200)Hg = 0.03 ± 0.02‰, 1σ) and recently accumulated peat (Δ(199)Hg = -0.22 ± 0.06‰, Δ(200)Hg = 0.00 ± 0.04‰, 1σ) are characteristic of GEM (Δ(199)Hg = -0.17 ± 0.07‰, Δ(200)Hg = -0.05 ± 0.02‰, 1σ), and differs from wet deposition (Δ(199)Hg = 0.73 ± 0.15‰, Δ(200)Hg = 0.21 ± 0.04‰, 1σ). Sphagnum covered during three years by transparent and opaque surfaces, which eliminate wet deposition, continue to accumulate Hg. Sphagnum Hg isotope signatures indicate accumulation to take place by GEM dry deposition, and indicate little photochemical re-emission. We estimate that atmospheric mercury deposition to the peat bog surface is dominated by GEM dry deposition (79%) rather than wet deposition (21%). Consequently, peat deposits are potential records of past atmospheric GEM concentrations and isotopic composition.
Collapse
Affiliation(s)
- Maxime Enrico
- ECOLAB, Université de Toulouse, CNRS, INPT, UPS, France; ENSAT, Avenue de l'Agrobiopole, 31326 Castanet Tolosan, France
- Observatoire Midi-Pyrénées, Laboratoire Géosciences Environnement Toulouse, CNRS/IRD/Université Paul Sabatier Toulouse III , 14 avenue Edouard Belin, 31400 Toulouse, France
| | - Gaël Le Roux
- ECOLAB, Université de Toulouse, CNRS, INPT, UPS, France; ENSAT, Avenue de l'Agrobiopole, 31326 Castanet Tolosan, France
| | - Nicolas Marusczak
- Observatoire Midi-Pyrénées, Laboratoire Géosciences Environnement Toulouse, CNRS/IRD/Université Paul Sabatier Toulouse III , 14 avenue Edouard Belin, 31400 Toulouse, France
| | - Lars-Eric Heimbürger
- Observatoire Midi-Pyrénées, Laboratoire Géosciences Environnement Toulouse, CNRS/IRD/Université Paul Sabatier Toulouse III , 14 avenue Edouard Belin, 31400 Toulouse, France
| | - Adrien Claustres
- ECOLAB, Université de Toulouse, CNRS, INPT, UPS, France; ENSAT, Avenue de l'Agrobiopole, 31326 Castanet Tolosan, France
| | - Xuewu Fu
- Observatoire Midi-Pyrénées, Laboratoire Géosciences Environnement Toulouse, CNRS/IRD/Université Paul Sabatier Toulouse III , 14 avenue Edouard Belin, 31400 Toulouse, France
| | - Ruoyu Sun
- Observatoire Midi-Pyrénées, Laboratoire Géosciences Environnement Toulouse, CNRS/IRD/Université Paul Sabatier Toulouse III , 14 avenue Edouard Belin, 31400 Toulouse, France
| | - Jeroen E Sonke
- Observatoire Midi-Pyrénées, Laboratoire Géosciences Environnement Toulouse, CNRS/IRD/Université Paul Sabatier Toulouse III , 14 avenue Edouard Belin, 31400 Toulouse, France
| |
Collapse
|
37
|
Impact of Measurement Uncertainties on Receptor Modeling of Speciated Atmospheric Mercury. Sci Rep 2016; 6:20676. [PMID: 26857835 PMCID: PMC4746649 DOI: 10.1038/srep20676] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 12/30/2015] [Indexed: 11/21/2022] Open
Abstract
Gaseous oxidized mercury (GOM) and particle-bound mercury (PBM) measurement uncertainties could potentially affect the analysis and modeling of atmospheric mercury. This study investigated the impact of GOM measurement uncertainties on Principal Components Analysis (PCA), Absolute Principal Component Scores (APCS), and Concentration-Weighted Trajectory (CWT) receptor modeling results. The atmospheric mercury data input into these receptor models were modified by combining GOM and PBM into a single reactive mercury (RM) parameter and excluding low GOM measurements to improve the data quality. PCA and APCS results derived from RM or excluding low GOM measurements were similar to those in previous studies, except for a non-unique component and an additional component extracted from the RM dataset. The percent variance explained by the major components from a previous study differed slightly compared to RM and excluding low GOM measurements. CWT results were more sensitive to the input of RM than GOM excluding low measurements. Larger discrepancies were found between RM and GOM source regions than those between RM and PBM. Depending on the season, CWT source regions of RM differed by 40–61% compared to GOM from a previous study. No improvement in correlations between CWT results and anthropogenic mercury emissions were found.
Collapse
|
38
|
Castro MS, Sherwell J. Effectiveness of Emission Controls to Reduce the Atmospheric Concentrations of Mercury. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:14000-14007. [PMID: 26606506 DOI: 10.1021/acs.est.5b03576] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Coal-fired power plants in the United States are required to reduce their emissions of mercury (Hg) into the atmosphere to lower the exposure of Hg to humans. The effectiveness of power-plant emission controls on the atmospheric concentrations of Hg in the United States is largely unknown because there are few long-term high-quality atmospheric Hg data sets. Here, we present the atmospheric concentrations of Hg and sulfur dioxide (SO2) measured from 2006 to 2015 at a relatively pristine location in western Maryland that is several (>50 km) kilometers downwind of power plants in Ohio, Pennsylvania, and West Virginia. Annual average atmospheric concentrations of gaseous oxidized mercury (GOM), SO2, fine particulate mercury (PBM2.5), and gaseous elemental mercury (GEM) declined by 75%, 75%, 43%, and 13%, respectively, and were strongly correlated with power-plant Hg emissions from the upwind states. These results provide compelling evidence that reductions in Hg emissions from power plants in the United States had their intended impact to reduce regional Hg pollution.
Collapse
Affiliation(s)
- Mark S Castro
- Appalachian Laboratory, University of Maryland Center for Environmental Science , 301 Braddock Road, Frostburg, Maryland 21532, United States
| | - John Sherwell
- Power Plant Research Program, Maryland Department of Natural Resources , Annapolis, Maryland 21401, United States
| |
Collapse
|
39
|
Miller MB, Fine R, Pierce AM, Gustin MS. Identifying sources of ozone to three rural locations in Nevada, USA, using ancillary gas pollutants, aerosol chemistry, and mercury. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 530-531:483-492. [PMID: 25957787 DOI: 10.1016/j.scitotenv.2015.03.146] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Revised: 03/18/2015] [Accepted: 03/22/2015] [Indexed: 06/04/2023]
Abstract
Ozone (O3) is a secondary air pollutant of long standing and increasing concern for environmental and human health, and as such, the US Environmental Protection Agency will revise the National Ambient Air Quality Standard of 75 ppbv to ≤ 70 ppbv. Long term measurements at the Great Basin National Park (GBNP) indicate that O3 in remote areas of Nevada will exceed a revised standard. As part of the Nevada Rural Ozone Initiative, measurements of O3 and other air pollutants were made at 3 remote sites between February 2012 and March 2014, GBNP, Paradise Valley (PAVA), and Echo Peak (ECHO). Exceptionally high concentrations of each air pollutant were defined relative to each site as mixing ratios that exceeded the 90th percentile of all hourly data. Case studies were analyzed for all periods during which mean daily O3 exceeded the 90th percentile concurrently with a maximum 8-h average (MDA8) O3 that was "exceptionally high" for the site (65 ppbv at PAVA, 70 ppbv at ECHO and GBNP), and of potential regulatory significance. An MDA8 ≥ 65 ppbv occurred only five times at PAVA, whereas this occurred on 49 and 65 days at GBNP and ECHO, respectively. The overall correlation between O3 and other pollutants was poor, consistent with the large distance from significant primary emission sources. Mean CO at these locations exceeded concentrations reported for background sites in 2000. Trajectory residence time calculations and air pollutant concentrations indicate that exceedances at GBNP and ECHO were promoted by air masses originating from multiple sources, including wildfires, transport of pollution from southern California and the marine boundary layer, and transport of Asian pollution plumes. Results indicate that the State of Nevada will exceed a revised O3 standard due to sources that are beyond their control.
Collapse
Affiliation(s)
- Matthieu B Miller
- Department of Natural Resources and Environmental Science, University of Nevada-Reno, 1664 N. Virginia St, Reno NV, USA.
| | - Rebekka Fine
- Department of Natural Resources and Environmental Science, University of Nevada-Reno, 1664 N. Virginia St, Reno NV, USA
| | - Ashley M Pierce
- Department of Natural Resources and Environmental Science, University of Nevada-Reno, 1664 N. Virginia St, Reno NV, USA
| | - Mae S Gustin
- Department of Natural Resources and Environmental Science, University of Nevada-Reno, 1664 N. Virginia St, Reno NV, USA.
| |
Collapse
|
40
|
Huang J, Gustin MS. Uncertainties of Gaseous Oxidized Mercury Measurements Using KCl-Coated Denuders, Cation-Exchange Membranes, and Nylon Membranes: Humidity Influences. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:6102-6108. [PMID: 25877790 DOI: 10.1021/acs.est.5b00098] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Quantifying the concentration of gaseous oxidized mercury (GOM) and identifying the chemical compounds in the atmosphere are important for developing accurate local, regional, and global biogeochemical cycles. The major hypothesis driving this work was that relative humidity affects collection of GOM on KCl-coated denuders and nylon membranes, both currently being applied to measure GOM. Using a laboratory manifold system and ambient air, GOM capture efficiency on 3 different collection surfaces, including KCl-coated denuders, nylon membranes, and cation-exchange membranes, was investigated at relative humidity ranging from 25 to 75%. Recovery of permeated HgBr2 on KCl-coated denuders declined by 4-60% during spikes of relative humidity (25 to 75%). When spikes were turned off GOM recoveries returned to 60 ± 19% of permeated levels. In some cases, KCl-coated denuders were gradually passivated over time after additional humidity was applied. In this study, GOM recovery on nylon membranes decreased with high humidity and ozone concentrations. However, additional humidity enhanced GOM recovery on cation-exchange membranes. In addition, reduction and oxidation of elemental mercury during experiments was observed. The findings in this study can help to explain field observations in previous studies.
Collapse
Affiliation(s)
- Jiaoyan Huang
- Department of Natural Resources and Environmental Sciences, University of Nevada-Reno, 1664 North Virginia Street, Reno, Nevada, 89557, United States
| | - Mae Sexauer Gustin
- Department of Natural Resources and Environmental Sciences, University of Nevada-Reno, 1664 North Virginia Street, Reno, Nevada, 89557, United States
| |
Collapse
|
41
|
Deeds DA, Ghoshdastidar A, Raofie F, Guérette ÉA, Tessier A, Ariya PA. Development of a Particle-Trap Preconcentration-Soft Ionization Mass Spectrometric Technique for the Quantification of Mercury Halides in Air. Anal Chem 2015; 87:5109-16. [DOI: 10.1021/ac504545w] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Daniel A. Deeds
- Department
of Atmospheric and Oceanic Sciences, McGill University, Montreal, Quebec H3A 2K6, Canada
| | - Avik Ghoshdastidar
- Department
of Chemistry, McGill University, Montreal, Quebec H3A 2K6, Canada
| | - Farhad Raofie
- Department
of Atmospheric and Oceanic Sciences, McGill University, Montreal, Quebec H3A 2K6, Canada
| | | | - Alain Tessier
- Centre
for Biological Applications of Mass Spectrometry, Concordia University, Montreal, Quebec, Canada
| | - Parisa A. Ariya
- Department
of Atmospheric and Oceanic Sciences, McGill University, Montreal, Quebec H3A 2K6, Canada
- Department
of Chemistry, McGill University, Montreal, Quebec H3A 2K6, Canada
| |
Collapse
|
42
|
Huang J, Gustin MS. Use of passive sampling methods and models to understand sources of mercury deposition to high elevation sites in the Western United States. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:432-41. [PMID: 25485926 DOI: 10.1021/es502836w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
To understand gaseous oxidized mercury (GOM) sources to the Western US, data were collected with passive samplers for ambient GOM concentrations and dry deposition at 10 sites from the coast of the Pacific Ocean to Great Basin National Park. Tests were done to better understand the samplers and the materials used. Measured dry deposition of GOM was significantly higher at sites >2000 m elevation relative to those below due to high GOM concentrations and atmospheric turbulence. At these high elevation sites, GOM dry deposition was higher in spring due to long-range transport from Asia (air parcels from the free troposphere) and some high GOM dry deposition events were related to regional emissions. Dry deposition of GOM at two sites was calculated using the passive sampler data and a multiple-resistance model. A previously developed relationship between the sampling rate of the passive sampler and GOM concentrations was used to estimate dry deposition and a scaling factor of 3 was used to adjust GOM concentrations, due to underestimation by KCl-coated denuder measurements. With the scaling factor of 3, modeled deposition was in the range of results estimated from two different models settings. However, dry deposition did not correlate consistently with either model. The disagreement could be due to uncertainties associated with measurements and/or modeling, or different GOM compounds existing in the atmosphere. If the atmospheric GOM compounds are known, dry deposition velocities could be estimated more accurately. Lastly, we investigated the potential for use of a new sampling material for GOM and checked the efficiency of the passive sampler.
Collapse
Affiliation(s)
- Jiaoyan Huang
- Department of Natural Resources and Environmental Sciences, University of Nevada, Reno , 1664 N. Virginia Street, Reno, Nevada 89557, United States
| | | |
Collapse
|
43
|
McClure CD, Jaffe DA, Edgerton ES. Evaluation of the KCl denuder method for gaseous oxidized mercury using HgBr2 at an in-service AMNet site. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:11437-44. [PMID: 25192054 DOI: 10.1021/es502545k] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
During the summer of 2013, we examined the performance of KCl-coated denuders for measuring gaseous oxidized mercury (GOM) by calibrating with a known source of GOM (i.e., HgBr2) at the North Birmingham SouthEastern Aerosol Research and Characterization (SEARCH) site. We found that KCl-coated denuders have near 95% collection efficiency for HgBr2 in zero air (i.e., air scrubbed of mercury and ozone). However, in ambient air, the efficiency of KCl-coated denuders in capturing HgBr2 dropped to 20-54%. We also found that absolute humidity and ozone each demonstrate a significant inverse correlation with HgBr2 recovery in ambient air. Subsequent laboratory tests with HgBr2 and the KCl-coated denuder show that ozone and absolute humidity cause the release of gaseous elemental Hg from the denuder and thus appear to explain the low recovery in ambient air. Based on these findings, we infer that the KCl denuder method underestimates atmospheric GOM concentrations and a calibration system is needed to accurately measure GOM. The system described in this paper for HgBr2 could be implemented with existing mercury speciation instrumentation and this would improve our knowledge of the response to one potentially important GOM compound.
Collapse
Affiliation(s)
- Crystal D McClure
- Department of Atmospheric Science, University of Washington , 408 ATG Building, Box 351640, Seattle, Washington 98195, United States
| | | | | |
Collapse
|
44
|
A Survey of Mercury in Air and Precipitation across Canada: Patterns and Trends. ATMOSPHERE 2014. [DOI: 10.3390/atmos5030635] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
45
|
Huang J, Lyman SN, Hartman JS, Gustin MS. A review of passive sampling systems for ambient air mercury measurements. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2014; 16:374-392. [PMID: 24362622 DOI: 10.1039/c3em00501a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Atmospheric mercury (Hg) temporal and spatial patterns must be measured accurately in order to adequately understand the role of this pathway as it relates to Hg toxicity and exposure of humans and wildlife to Hg. It is also important to understand the distribution of the different chemical forms (elemental, oxidized, or particle bound) and specific compounds in air (e.g., HgCl2, HgBr2, HgO, Hg(NO3)2, and HgSO4). However, the current automated and passive sampling methods of measurement have limitations and artifacts impacting our ability to achieve this task. Both abiotic and biotic systems have been developed to measure the total gaseous Hg and oxidized Hg compounds (concentration and deposition). This study reviews and compares the performance of previously and currently applied passive sampling systems. Computable fluid dynamic modeling was conducted to gain additional understanding of a gaseous oxidized Hg (GOM) passive sampler. Case studies during which passive samplers were used are also presented to demonstrate the ability of passive samplers to capture atmospheric Hg variation. A network using passive samplers would be useful for monitoring global Hg trends due to the limits of the current automated method.
Collapse
Affiliation(s)
- Jiaoyan Huang
- Department of Natural Resources and Environmental Sciences, University of Nevada, Reno, 1664 N. Virginia Street, Reno, NV 89557, USA.
| | | | | | | |
Collapse
|
46
|
Wright G, Gustin MS, Weiss-Penzias P, Miller MB. Investigation of mercury deposition and potential sources at six sites from the Pacific Coast to the Great Basin, USA. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 470-471:1099-1113. [PMID: 24252197 DOI: 10.1016/j.scitotenv.2013.10.071] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2013] [Revised: 10/17/2013] [Accepted: 10/19/2013] [Indexed: 06/02/2023]
Abstract
The Western Airborne Contaminants Assessment Project showed that USA National Parks had fish mercury (Hg) concentrations above threshold concentrations set for wildlife. Since significant areas of the Western USA are arid, we hypothesized that dry deposition would be important. The primary question was whether sources of Hg were local and thus, easily addressed, or regional (from within the United States), or global (long range transport), and more difficult to address. To investigate this, surrogate surfaces and passive samplers for the measurement of GOM deposition and concentration, respectively, were deployed from the coast of California to the eastern edge of Nevada. Meteorological data, back trajectory modeling, and ozone concentrations were applied to better understand potential sources of Hg. Lowest seasonal mean Hg deposition (0.2 to 0.4 ng m(-2)h(-1)) was observed at low elevation (<100 m) Pacific Coast sites. Highest values were recorded at Lick Observatory, a high elevation coastal site (1,279 m), and Great Basin National Park (2,062 m) in rural eastern Nevada (1.5 to 2.4 ng m(-2)h(-1)). Intermediate values were recorded in Yosemite and Sequoia National Parks (0.9 to 1.2 ng m(-2)h(-1)). Results indicate that local, regional and global sources of air pollution, specifically oxidants, are contributing to observed deposition. At Great Basin National Park air chemistry was influenced by regional urban and agricultural emissions and free troposphere inputs. Dry deposition contributed ~2 times less Hg than wet deposition at the coastal locations, but 3 to 4 times more at the higher elevation sites. Based on the spatial trends, oxidation in the marine boundary layer or ocean sources contributed ~0.4 ng m(-2)h(-1) at the coastal locations. Regional pollution and long range transport contributed 1 to 2 ng m(-2)h(-1) to other locations, and the source of Hg is global and as such, all sources are important to consider.
Collapse
Affiliation(s)
- Genine Wright
- Department of Natural Resources and Environmental Science, University of Nevada-Reno, MS186, Reno, NV 89557, United States
| | - Mae Sexauer Gustin
- Department of Natural Resources and Environmental Science, University of Nevada-Reno, MS186, Reno, NV 89557, United States.
| | - Peter Weiss-Penzias
- Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, United States
| | - Matthieu B Miller
- Department of Natural Resources and Environmental Science, University of Nevada-Reno, MS186, Reno, NV 89557, United States
| |
Collapse
|
47
|
Regional Air Quality Model Application of the Aqueous-Phase Photo Reduction of Atmospheric Oxidized Mercury by Dicarboxylic Acids. ATMOSPHERE 2013. [DOI: 10.3390/atmos5010001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
48
|
Huang J, Chang FC, Wang S, Han YJ, Castro M, Miller E, Holsen TM. Mercury wet deposition in the eastern United States: characteristics and scavenging ratios. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2013; 15:2321-2328. [PMID: 24190422 DOI: 10.1039/c3em00454f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Wet deposition is an important atmospheric mercury (Hg) pathway between air and terrestrial ecosystems. It is measured at numerous locations in the United States (U. S.) as part of the Mercury Deposition Network (MDN). The annual Hg wet deposition flux in 2009 at four locations in the northeastern U. S. (MDN sites MD08, VT99, NY20, and NY43) ranged from 6.4 to 13.4 μg per m(2) year which is higher than modeled reactive Hg (RM) dry deposition for this region. The highest ambient RM concentrations were seen at MD08, which is closest to significant anthropogenic sources; however, the volume-weighted mean Hg concentrations in precipitation were similar at these four sites. Mass based scavenging ratios (SC) of RM ranged from 1700 to 4500. Differences in SCs were likely a result of differences in meteorological conditions, the forms of RM in the atmosphere, vertical concentration variations, and measurement uncertainties, including precipitation depth and RM concentrations. RM SCs were higher than those reported for other soluble species. Multiple linear regression suggests that gaseous oxidized Hg is responsible for the majority of the scavenged RM.
Collapse
Affiliation(s)
- Jiaoyan Huang
- Department of Natural Resources and Environmental Sciences, University of Nevada, Reno, NV 89557, USA
| | | | | | | | | | | | | |
Collapse
|