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Schlippe-Justicia L, Lemaire J, Dittrich C, Mayer M, Bustamante P, Rojas B. Poison in the nursery: Mercury contamination in the tadpole-rearing sites of an Amazonian frog. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169450. [PMID: 38135067 DOI: 10.1016/j.scitotenv.2023.169450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 12/11/2023] [Accepted: 12/15/2023] [Indexed: 12/24/2023]
Abstract
Artisanal and small-scale gold mining (ASGM) has become a major threat for Neotropical forests. This technique for obtaining gold is a substantial driver of small-scale deforestation and the largest contributor of Hg emissions to both the atmosphere and freshwater systems globally. Previous studies have demonstrated the impacts of Hg accumulation on various aquatic ecosystems and organisms. However, its consequences in other, more discrete systems such as phytotelmata (water-holding plant structures), and the organisms therein, have so far gone unnoticed. Here, we show high concentrations of Hg (mean ± SD: 1.43 ± 2.19 ppm) in phytotelmata and other small pools, the aquatic microenvironments used by the Neotropical poison frog Dendrobates tinctorius as tadpole-rearing sites. In 17 % of the cases, we detected Hg concentrations above the severe effect level (SEL = 2 ppm) for freshwater sediments. Hg concentrations varied depending on pool characteristics and tended to increase in proximity to known ASGM sites. We did not find an effect of Hg concentration on the number of D. tinctorius tadpoles in a given pool. Tadpoles were found in pools with concentrations of up to 8.68 ppm, suggesting that D. tinctorius fathers do not avoid pools with high Hg levels for tadpole deposition. While further research is needed to determine the potential effects of Hg on tadpole development, we found an intriguing tendency for tadpoles in later developmental stages to have lower body condition when occurring in pools with higher Hg concentrations. Our findings provide evidence of relevant Hg concentrations in the terrestrial water systems used by phytotelm-breeding anurans, and highlight the need of further field and experimental studies investigating the implications of Hg contamination for tadpole development and behaviour and the overall conservation of Amazonian biodiversity.
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Affiliation(s)
- Lia Schlippe-Justicia
- Department of Interdisciplinary Life Sciences, Konrad Lorenz Institute of Ethology, University of Veterinary Medicine Vienna, Savoyenstraße 1, 1160 Vienna, Austria.
| | - Jérémy Lemaire
- Department of Behavioral and Cognitive Biology, University of Vienna, Djerassiplatz 1, 1030 Vienna, Austria
| | - Carolin Dittrich
- Department of Interdisciplinary Life Sciences, Konrad Lorenz Institute of Ethology, University of Veterinary Medicine Vienna, Savoyenstraße 1, 1160 Vienna, Austria; University of Jyvaskyla, Department of Biology and Environmental Science, P.O. Box 35, 40014 Jyväskylä, Finland
| | - Martin Mayer
- Department of Forestry and Wildlife Management, Inland Norway University of Applied Sciences, Anne Evenstads Vei 80, 2480 Koppang, Norway; Department of Ecoscience, Aarhus University, Nordre Ringgade 1, 8000 Aarhus, Denmark
| | - Paco Bustamante
- Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 2 rue Olympe de Gouges, 17000 La Rochelle, France
| | - Bibiana Rojas
- Department of Interdisciplinary Life Sciences, Konrad Lorenz Institute of Ethology, University of Veterinary Medicine Vienna, Savoyenstraße 1, 1160 Vienna, Austria; University of Jyvaskyla, Department of Biology and Environmental Science, P.O. Box 35, 40014 Jyväskylä, Finland.
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Li J, Liu JZ, Tai XS, Jiao L, Zhang M, Zang F. Pollution and source-specific risk analysis of potentially toxic metals in urban soils of an oasis-tourist city in northwest China. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2024; 46:55. [PMID: 38263529 DOI: 10.1007/s10653-023-01850-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 12/27/2023] [Indexed: 01/25/2024]
Abstract
Source-specific risk apportionment for soil potentially toxic metals (PTMs) is of great significance for contamination prevention and risk management in urban environments. Eighty-five urban soil samples were obtained from an oasis-tourist city, China and examined for eight PTMs (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn). The pollution levels, sources, and ecological risk of soil PTMs were quantified, and their source-specific ecological and human health effects were also estimated using the multi-proxy approaches. The results demonstrated that accumulation of Cd, Hg, Pb, Cr, Cu, and Zn in soils was observed compared to their background levels, and the soils experienced varying degrees of PTMs pollution, especially at sites with high-intensity anthropogenic activities. Natural sources, atmospheric deposition, industrial sources, vehicular emissions, and comprehensive inputs were the principal sources, with contributions of 29.28%, 25.86%, 20.13%, 16.50%, and 8.23%, respectively. The integrated ecological risks of PTMs in soils were moderate at most sites, with atmospheric deposition being the dominant contributor to ecological risks. Children exhibited pronounced non-cancer risks, but adults had no notable non-cancer risks. Moreover, there were potential carcinogenic risks for both children and adults within the study region. Non-cancer and carcinogenic risks were more significant for children than adults, and traffic emissions were the primary contributor to non-cancer risks (adults: 20.53%, children: 20.49%) and carcinogenic risks (adults: 22.95%, children: 22.08%). The industrial and traffic activities were considered as priority control sources for soil pollution control and risk management, with Hg, Cd, Zn, and Pb corresponding to the priority elements. This study highlights the source-specific ecological and human health effects of PTMs pollution in urban soils, thereby providing valuable information for targeted pollution control and priority source management.
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Affiliation(s)
- Jun Li
- College of Urban Environment, Lanzhou City University, Lanzhou, 730070, China.
| | - Jun-Zhuo Liu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Xi-Sheng Tai
- College of Urban Environment, Lanzhou City University, Lanzhou, 730070, China
| | - Liang Jiao
- Key Laboratory of Resource Environment and Sustainable Development of Oasis, Gansu Province, Northwest Normal University, Lanzhou, 730070, China
| | - Ming Zhang
- College of Urban Environment, Lanzhou City University, Lanzhou, 730070, China
| | - Fei Zang
- College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, China
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Shi T, Zhan P, Shen Y, Wang H, Wu C, Li J. Using multi-technology to characterize transboundary Hg pollution in the largest presently active Hg deposit in China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023:10.1007/s11356-023-28080-0. [PMID: 37322398 DOI: 10.1007/s11356-023-28080-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 05/31/2023] [Indexed: 06/17/2023]
Abstract
Active Hg mines are primary sources of Hg contamination in the environment of mining districts and surrounding areas. Alleviation of Hg pollution requires knowledge of pollution sources, migration, and transform pathways across various environmental media. Accordingly, the Xunyang Hg-Sb mine, the largest active Hg deposit in China, presently was selected as the study area. GIS, TIMA, EPMA, μ-XRF, TEM-EDS, and Hg stable isotopes were adopted to investigate the spatial distribution, mineralogical characteristics, in situ microanalysis, and pollution sources of Hg in the environment medium at the macro- and micro-levels. The total Hg concentration in samples showed a regional distribution, with higher levels in areas close to the mining operations. The in situ distribution of Hg in soil was mainly associated with the mineralogical phases of quartz, and Hg was also correlated with Sb and S. Hg was also found to be rich mainly in quartz minerals in the sediment and showed different distributions of Sb. Hg hotspots had S abundances and contained no Sb and O. The contributions from the anthropogenic sources to soil Hg were estimated to be 55.35%, among which 45.97% from unroasted Hg ore and 9.38% from tailing. Natural input of soil Hg due to pedogenic processes accounted for 44.65%. Hg in corn grain was mainly derived from the atmosphere. This study will provide a scientific basis for assessing the current environmental quality in this area and minimizing further impacts that affect the nearby environmental medium.
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Affiliation(s)
- Taoran Shi
- School of Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China.
| | - Pei Zhan
- School of Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China
| | - Yaqin Shen
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Hongyan Wang
- Beijing Dabeinong Technology Group Co., Ltd., Beijing, 100000, China
| | - Chunfa Wu
- School of Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China
| | - Jining Li
- School of Environment, Nanjing Normal University, Nanjing, 210023, China
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Du H, Gu X, Johs A, Yin X, Spano T, Wang D, Pierce EM, Gu B. Sonochemical oxidation and stabilization of liquid elemental mercury in water and soil. JOURNAL OF HAZARDOUS MATERIALS 2023; 445:130589. [PMID: 37055993 DOI: 10.1016/j.jhazmat.2022.130589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 11/23/2022] [Accepted: 12/08/2022] [Indexed: 06/19/2023]
Abstract
Over 3000 mercury (Hg)-contaminated sites worldwide contain liquid metallic Hg [Hg(0)l] representing a continuous source of elemental Hg(0) in the environment through volatilization and solubilization in water. Currently, there are few effective treatment technologies available to remove or sequester Hg(0)l in situ. We investigated sonochemical treatments coupled with complexing agents, polysulfide and sulfide, in oxidizing Hg(0)l and stabilizing Hg in water, soil and quartz sand. Results indicate that sonication is highly effective in breaking up and oxidizing liquid Hg(0)l beads via acoustic cavitation, particularly in the presence of polysulfide. Without complexing agents, sonication caused only minor oxidation of Hg(0)l but increased headspace gaseous Hg(0)g and dissolved Hg(0)aq in water. However, the presence of polysulfide essentially stopped Hg(0) volatilization and solubilization. As a charged polymer, polysulfide was more effective than sulfide in oxidizing Hg(0)l and subsequently stabilizing the precipitated metacinnabar (β-HgS) nanocrystals. Sonochemical treatments with sulfide yielded incomplete oxidation of Hg(0)l, likely resulting from the formation of HgS coatings on the dispersed µm-size Hg(0)l bead surfaces. Sonication with polysulfide also resulted in rapid oxidation of Hg(0)l and precipitation of HgS in quartz sand and in the Hg(0)l-contaminated soil. This research indicates that sonochemical treatment with polysulfide could be an effective means in rapidly converting Hg(0)l to insoluble HgS precipitates in water and sediments, thereby preventing its further emission and release to the environment. We suggest that future studies are performed to confirm its technical feasibility and treatment efficacy for remediation applications.
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Affiliation(s)
- Hongxia Du
- College of Resources and Environment, Southwest University, Chongqing 400715, PR China; Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Xin Gu
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Alexander Johs
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Xiangping Yin
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Tyler Spano
- Nuclear Nonproliferation Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Dingyong Wang
- College of Resources and Environment, Southwest University, Chongqing 400715, PR China
| | - Eric M Pierce
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Baohua Gu
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States; Department of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, TN 37996, United States.
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Zupančič M, Šušteršič M, Bavec Š, Gosar M. Oral and inhalation bioaccessibility of potentially toxic elements in household dust from former Hg mining district, Idrija, Slovenia. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2021; 43:3505-3531. [PMID: 33570697 DOI: 10.1007/s10653-021-00835-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 01/23/2021] [Indexed: 06/12/2023]
Abstract
One of the main sources of potential chronic exposure to potentially toxic elements is household dust, especially in an environment with known point sources of PTE pollution. The literature review clearly shows that the total concentrations of an element in the environment do not provide information to predict its bioavailability. The aim of the present study was to evaluate the oral and inhalation bioaccessibility of PTE present in household dust in the small town of Idrija, the site of the former mercury mine. Unified bioaccessibility method was used to assess oral bioaccessibility of PTE in the stomach and intestine, while inhalation bioaccessibility was assessed by extraction of household dust samples with two synthetic extraction solutions-Gamble's solution (GS) and artificial lysosomal fluid (ALF). A low bioaccessibility of mercury was observed in all synthetic solutions (less than 3%). The highest bioaccessibility of PTE was observed in ALF solution, especially for Zn, Pb and Cd. Only a slightly lower bioaccessibility of these three elements was also observed in the stomach, while the bioaccessibility of other elements in the gastric phase was less than 40%. In general, the bioaccessibility of all elements decreased in the intestine. With the exception of Cr, the lowest bioaccessibility of the elements was observed in GS. Daily ingestion and inhalation doses of PTE from household dust were calculated and their values were below the available recommended or tolerable daily intakes of PTE from food according to the European Food Safety Authority.
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Affiliation(s)
- Marija Zupančič
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, 1000, Ljubljana, Slovenia.
| | | | - Špela Bavec
- Geological Survey of Slovenia, Dimičeva ulica 14, 1000, Ljubljana, Slovenia
| | - Mateja Gosar
- Geological Survey of Slovenia, Dimičeva ulica 14, 1000, Ljubljana, Slovenia
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O'Shea MJ, Krekeler MPS, Vann DR, Gieré R. Investigation of Pb-contaminated soil and road dust in a polluted area of Philadelphia. ENVIRONMENTAL MONITORING AND ASSESSMENT 2021; 193:440. [PMID: 34164717 PMCID: PMC8415436 DOI: 10.1007/s10661-021-09213-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 06/12/2021] [Indexed: 05/27/2023]
Abstract
A multi-analytical geochemical investigation of Pb-contaminated collocated road dust and soils, at two size fractions, was performed in Fishtown, Philadelphia, PA, USA. The combinations of methods employed in this case study were chosen to better characterize the contamination, enhance identification of pollution sources, improve understanding of the impact of former Pb smelters, and to study the relationships between two media and between two size fractions. High concentrations of Cu and Sn were observed in both bulk and finer road dust, whereas large concentrations of Zn and Pb were found in both bulk and finer soil samples, implying pollution. There were no obvious associations between Pb soil concentrations and former smelter locations. Therefore, the primary source of the high mean Pb content in bulk (595 ppm) and fine soils (687 ppm) was likely legacy lead paint and/or leaded-gasoline products. Using electron microscopy, we found that Pb particles were mainly 0.1-10 µm in diameter and were ubiquitous in both soil and dust samples. Two-way analysis of variance tests revealed that, for most chemical elements explored here, there were statistically significant differences in concentrations based on media and size fractions, with finer sizes being more polluted than the bulk. The mineralogical composition and the sources of several pollutant elements (Cr, Cu, Zn, Pb), however, were similar for both soil and dust, pointing to material exchange between the two media. We suggest that future investigations of collocated road dust and soils in urban environments use the methodologies applied in this study to obtain detailed insights into sources of roadside pollution and the relationships between neighboring media.
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Affiliation(s)
- Michael J O'Shea
- Department of Earth and Environmental Science, University of Pennsylvania, Philadelphia, PA, 19104-6316, USA.
| | - Mark P S Krekeler
- Department of Geology and Environmental Earth Science, Miami University Hamilton, Hamilton, OH, 45011, USA
- Department of Geology and Environmental Earth Science, Miami University, Oxford, OH, 45056, USA
| | - David R Vann
- Department of Earth and Environmental Science, University of Pennsylvania, Philadelphia, PA, 19104-6316, USA
| | - Reto Gieré
- Department of Earth and Environmental Science, University of Pennsylvania, Philadelphia, PA, 19104-6316, USA
- Center of Excellence in Environmental Toxicology, University of Pennsylvania, Philadelphia, PA, 19104-6316, USA
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O'Shea MJ, Vigliaturo R, Choi JK, McKeon TP, Krekeler MPS, Gieré R. Alteration of yellow traffic paint in simulated environmental and biological fluids. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 750:141202. [PMID: 32853929 PMCID: PMC7657991 DOI: 10.1016/j.scitotenv.2020.141202] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 07/16/2020] [Accepted: 07/21/2020] [Indexed: 05/27/2023]
Abstract
Pollution from heavy metals in urban environments is a topic of growing concern because many metals, including Pb and Cr, are a human health hazard. Exposure to Pb and Cr has been linked to the inhibition of neurological development as well as toxic effects on many organs. Yellow traffic paint (YTP) is a mixture that contains organic polymers, binders, and pigments, which in some cases consist of crocoite (PbCrO4) that may be coated by silica. The primary aim of this study was to investigate the behavior of the crocoite pigment grains within YTP and their silica coatings in simulated environmental and human body conditions. To do this, both YTP and asphalt were collected in Philadelphia, PA, USA. These samples as well as a standard PbCrO4 were investigated with powder X-ray diffraction, X-ray fluorescence, environmental scanning electron microscopy (ESEM), transmission electron microscopy, and energy-dispersive X-ray spectroscopy. Using this multi-analytical approach, mineral phases were determined in the YTP, their shape, dimensional distributions, crystallinity, and chemical composition, as well as elemental distributions before and after experimental interactions. Three batch dissolution experiments with YTP, asphalt, and standard PbCrO4 were performed to simulate ingestion, inhalation, and environmental interaction with rainwater. Elemental releases were determined with inductively coupled plasma-optical emission spectrometry, and results indicated that little (ingestion) to no (environmental and inhalation) Pb and Cr were leached from the YTP during the three experimental procedures. This is likely due to the silica coating that encapsulates the crocoite particles, which persisted during all interactions. The ESEM results for YTP showed dimensional reductions after interactions with all three fluids. The silica coating must be further explored to determine how it breaks down in real environmental conditions.
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Affiliation(s)
- Michael J O'Shea
- Department of Earth and Environmental Science, University of Pennsylvania, Philadelphia, PA 19104-6316, USA.
| | - Ruggero Vigliaturo
- Department of Earth and Environmental Science, University of Pennsylvania, Philadelphia, PA 19104-6316, USA
| | - Jessica K Choi
- Department of Earth and Environmental Science, University of Pennsylvania, Philadelphia, PA 19104-6316, USA
| | - Thomas P McKeon
- Center of Excellence in Environmental Toxicology, University of Pennsylvania, Philadelphia, PA 19104-6316, USA
| | - Mark P S Krekeler
- Department of Geology and Environmental Earth Science, Miami University Hamilton, Hamilton, OH 45011, USA; Department of Geology and Environmental Earth Science, Miami University, Oxford, OH 45056, USA
| | - Reto Gieré
- Department of Earth and Environmental Science, University of Pennsylvania, Philadelphia, PA 19104-6316, USA; Center of Excellence in Environmental Toxicology, University of Pennsylvania, Philadelphia, PA 19104-6316, USA
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Wang Q, Zhang L, Liang X, Yin X, Zhang Y, Zheng W, Pierce EM, Gu B. Rates and Dynamics of Mercury Isotope Exchange between Dissolved Elemental Hg(0) and Hg(II) Bound to Organic and Inorganic Ligands. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:15534-15545. [PMID: 33196184 DOI: 10.1021/acs.est.0c06229] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Mercury (Hg) isotope exchange is a common process in biogeochemical transformations of Hg in the environment, but it is unclear whether and at what rates dissolved elemental Hg(0)aq may exchange with divalent Hg(II) bound to various organic and inorganic ligands in water. Using enriched stable isotopes, we investigated the rates and dynamics of isotope exchange between 202Hg(0)aq and 201Hg(II) bound to organic and inorganic ligands with varying chemical structures and binding affinities. Time-dependent exchange reactions were followed by isotope compositional changes using both inductively coupled plasma mass spectrometry and Zeeman cold vapor atomic absorption spectrometry. Rapid, spontaneous isotope exchange (<1 h) was observed between 202Hg(0)aq and 201Hg(II) bound to chloride (Cl-), ethylenediaminetetraacetate (EDTA), and thiols, such as cysteine (CYS), glutathione (GSH), and 2,3-dimercaptopropanesulfonic acid (DMPS) at a thiol ligand-to-Hg(II) molar ratio of 1:1. Without external reductants or oxidants, the exchange resulted in transfer of two electrons and redistribution of Hg isotopes bound to the ligand but no net changes of chemical species in the system. However, an increase in the ligand-to-Hg(II) ratio decreased the exchange rates due to the formation of 2:1 or higher thiol:Hg(II) chelated complexes, but had no effects on exchange rates with 201Hg(II) bound to EDTA or Cl-. The exchange between 202Hg(0)aq and 201Hg(II) bound to dissolved organic matter (DOM) showed an initially rapid followed by a slower exchange rate, likely resulting from Hg(II) complexation with both low- and high-affinity binding functional groups on DOM (e.g., carboxylates vs bidentate thiolates). These results demonstrate that Hg(0)aq readily exchanges with Hg(II) bound to various ligands and highlight the importance of considering exchange reactions in experimental enriched Hg isotope tracer studies or in natural abundance Hg isotope studies in environmental matrices.
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Affiliation(s)
- Quanying Wang
- Key Laboratory of Wet Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Lijie Zhang
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Xujun Liang
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Xiangping Yin
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Yaoling Zhang
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Wang Zheng
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Eric M Pierce
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Baohua Gu
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
- Department of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, Tennessee 37996, United States
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Žibret G. Influences of coal mines, metallurgical plants, urbanization and lithology on the elemental composition of street dust. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2019; 41:1489-1505. [PMID: 30554382 DOI: 10.1007/s10653-018-0228-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 12/04/2018] [Indexed: 06/09/2023]
Abstract
Street dust (SD) acts as a sink and a source of atmospheric particulate matter, which is especially significant in urban environments. World studies of natural and anthropogenic impacts on the elemental composition of SD are generally limited to specific areas or case studies. The objectives of this study are to determine the impacts of different anthropogenic atmospheric dust emitters and natural factors on the chemical composition of SD, and to define sources of variance in elemental composition of SD, temporal variations and geochemical associations of elements on large number of samples, collected in different time periods, anthropogenic environments and geological settings. Nested ANOVA shows that the majority of the elemental-level variations were found to be regional ones. Increased variations on local scale were observed for Hg, Mo, Ni, Zn and Ag. Increased temporal variations were observed for Zn, As, Cd and Pb. Spatial variations within the same sampling location were increased for Hg and Ag. Three anthropogenic geochemical associations were detected: Coal mining and coal-fired power production enriched SD with Al, Co, Fe, La, Sc, Th, Ti, V, Zr and U, metallurgy with Cr, V, Ni and Mn, and urbanization with Ag, Bi, Ca, Cd, Mg, Mo, Pb and Zn.
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Affiliation(s)
- Gorazd Žibret
- Geological Survey of Slovenia, Dimičeva ulica 14, 1000, Ljubljana, Slovenia.
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10
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Zheng W, Demers JD, Lu X, Bergquist BA, Anbar AD, Blum JD, Gu B. Mercury Stable Isotope Fractionation during Abiotic Dark Oxidation in the Presence of Thiols and Natural Organic Matter. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:1853-1862. [PMID: 30371069 DOI: 10.1021/acs.est.8b05047] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Mercury (Hg) stable isotope fractionation has been widely used to trace Hg sources and transformations in the environment, although many important fractionation processes remain unknown. Here, we describe Hg isotope fractionation during the abiotic dark oxidation of dissolved elemental Hg(0) in the presence of thiol compounds and natural humic acid. We observe equilibrium mass-dependent fractionation (MDF) with enrichment of heavier isotopes in the oxidized Hg(II) and a small negative mass-independent fractionation (MIF) owing to nuclear volume effects. The measured enrichment factors for MDF and MIF (ε202Hg and E199Hg) ranged from 1.10‰ to 1.56‰ and from -0.16‰ to -0.18‰, respectively, and agreed well with theoretically predicted values for equilibrium fractionation between Hg(0) and thiol-bound Hg(II). We suggest that the observed equilibrium fractionation was likely controlled by isotope exchange between Hg(0) and Hg(II) following the production of the Hg(II)-thiol complex. However, significantly attenuated isotope fractionation was observed during the initial stage of Hg(0) oxidation by humic acid and attributed to the kinetic isotope effect (KIE). This research provides additional experimental constraints on interpreting Hg isotope signatures with important implications for the use of Hg isotope fractionation as a tracer of the Hg biogeochemical cycle.
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Affiliation(s)
- Wang Zheng
- Environmental Sciences Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37830 , United States
| | - Jason D Demers
- Department of Earth and Environmental Sciences , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Xia Lu
- Environmental Sciences Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37830 , United States
| | - Bridget A Bergquist
- Department of Earth Sciences , University of Toronto , 22 Russell Street , Toronto , Ontario M5S 3B1 , Canada
| | | | - Joel D Blum
- Department of Earth and Environmental Sciences , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Baohua Gu
- Environmental Sciences Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37830 , United States
- Department of Biosystems Engineering and Soil Science , University of Tennessee , Knoxville , Tennessee 37996 , United States
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11
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Zhou Y, Aamir M, Liu K, Yang F, Liu W. Status of mercury accumulation in agricultural soil across China: Spatial distribution, temporal trend, influencing factor and risk assessment. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 240:116-124. [PMID: 29730420 DOI: 10.1016/j.envpol.2018.03.086] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 03/12/2018] [Accepted: 03/24/2018] [Indexed: 06/08/2023]
Abstract
Given its wide distribution in the natural environment and global transport potential, mercury (Hg) is regarded as a ubiquitous pollutant. In this study, we carried out nation-wide sampling campaigns across China to investigate the distribution of Hg in agricultural soils. Concentrations of Hg in the soils collected in 2011 and 2016 ranged from 0.04 to 0.69 and 0.06-0.78 mg kg-1, respectively. Based on the data from 2016, the reserve of Hg in the surface arable soils (0-20 cm) in China was 4.1 × 104 metric tons and Chinese cultivated soils accounted for 63.4-364 metric tons of Hg released to the global atmosphere. The soil Hg concentrations were significantly higher than the reference background level, highlighting the impacts of anthropogenic activities. The vertical distribution pattern showed a clear enrichment at the surface and a decrease with depth of the soils. Comparison of calculated geo-accumulation indexes among individual provinces showed that Northwest China had higher levels of Hg contamination than other regions of China, likely due to long-term energy related combustions in the area. Soil Hg level showed strong positive correlations with organic matter contents of soil, as well as the mean annual precipitation and temperature of the sampling locations. The non-carcinogenic human health risks of soil Hg were below the threshold level, but the general risk to the ecosystem was considerable. The increases in Hg accumulation from 2011 to 2016 at provincial level were found to relate to coal combustion, power generation and per capita GDP. This examination of energy consumption and socioeconomic drivers for China's soil Hg reserve increase is critical for direct Hg control by guiding policy-making and targets of technology development in era of rapid economic growth.
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Affiliation(s)
- Yuting Zhou
- International Joint Research Center for Persistent Toxic Substances, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Muhammad Aamir
- International Joint Research Center for Persistent Toxic Substances, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Kai Liu
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA 91125, USA
| | - Fangxing Yang
- International Joint Research Center for Persistent Toxic Substances, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Weiping Liu
- International Joint Research Center for Persistent Toxic Substances, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
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Baptista-Salazar C, Hintelmann H, Biester H. Distribution of mercury species and mercury isotope ratios in soils and river suspended matter of a mercury mining area. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2018; 20:621-631. [PMID: 29387859 DOI: 10.1039/c7em00443e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Mercury (Hg) released by mining activities can be dispersed in the environment, where it is subject to species transformations. Hg isotope ratios have been used to track sources in Hg contaminated areas, although it is unclear to what extent variations in δ-values are attributed to distinct Hg species. Hg was mined as Hg sulphide (cinnabar) in Idrija, Slovenia for centuries. Sediments are loaded with mining-residues (cinnabar and calcine), whereas contaminated soils mainly contain Hg bound to natural organic matter (NOM-Hg) related to atmospheric Hg deposition. Hg released from soils and sediments is transported as suspended matter (SM) in the Idrijca river to the Gulf of Trieste (GT), Italy. We determine Hg isotope ratios in river SM, sediments and soils from the Idrijca-catchment to decipher the Hg isotope ratio variability related to Hg species distribution in different grain-size fractions. δ202Hg values of SM collected from tributaries corresponded to those found in soils ranging from -2.58 to 0.19‰ and from -2.27 to -0.88‰, respectively. Speciation measurements reveal that fine fractions (0.45-20 μm) are dominated by NOM-Hg, while larger fractions contain more cinnabar. More negative δ202Hg values were related to higher proportions of NOM-Hg, which are predominant in soils and SM. Rain events increase SM-loads in the river, mainly due to resuspension of coarse grain-size fractions of bottom sediments bearing larger proportions of cinnabar, which leads to more positive δ202Hg values. The large magnitude of variation in δ202Hg and the smaller magnitude of variation in Δ199Hg (-0.37 to 0.09‰) are likely related to fractionation during ore roasting. Soil samples with high NOM-Hg content show more negative δ202Hg values and larger variation of Δ199Hg. More negative δ202Hg values in GT sediments were rather linked to distant sedimentation of soil derived NOM-Hg than to sedimentation of autochthonous marine material. Heterogeneity in the Idrija ore and ore processing likely produce large variations in the Hg isotopic composition of cinnabar and released metallic Hg, which complicate the differentiation of Hg sources. Combining Hg isotope measurements with solid phase Hg speciation reveals that Hg isotope ratios rather indicate different Hg species and are not necessarily symptomatic for Hg pollution sources.
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Affiliation(s)
- Carluvy Baptista-Salazar
- Institut für Geoökologie, Abt. Umweltgeochemie, Technische Universität Braunschweig, Langer Kamp 19c, Braunschweig, 38106, Germany.
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Bavec Š, Gosar M, Miler M, Biester H. Geochemical investigation of potentially harmful elements in household dust from a mercury-contaminated site, the town of Idrija (Slovenia). ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2017; 39:443-465. [PMID: 27056363 DOI: 10.1007/s10653-016-9819-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 03/18/2016] [Indexed: 06/05/2023]
Abstract
A comprehensive geochemical investigation of potentially harmful elements (PHEs) in household dust from the town of Idrija (Slovenia), once a world-famous Hg mining town that is now seriously polluted, was performed for the first time. After aqua regia digestion, the content of mercury (Hg), arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), molybdenum (Mo), nickel (Ni), lead (Pb) and zinc (Zn) was measured. PHE-bearing particles were recognised and observed by scanning electron microscopy and energy-dispersive spectrometry before and after exposure to simulated stomach acid (SSA). Mercury binding forms were identified by Hg thermal desorption technique and gastric bioaccessible Hg was estimated after SSA extraction by ICP-MS. With regard to rural and urban background values for Slovenia, high Hg content (6-120 mg/kg) and slightly elevated As content (1-13 mg/kg) were found. Mercury pollution is a result of past mining and ore processing activities. Arsenic content is potentially associated with As enrichment in local soils. Four Hg binding forms were identified: all samples contained Hg bound to the dust matrix, 14 samples contained cinnabar, two samples contained metallic Hg (Hg0), and one sample assumingly contained mercury oxide. After exposure to SSA, Hg-bearing phases showed no signs of dissolution, while other PHE-bearing phases were significantly morphologically and/or chemically altered. Estimated gastric Hg bioaccessibility was low (<0.006-0.09 %), which is in accordance with identified Hg binding forms and high organic carbon content (15.9-31.5 %) in the dust samples.
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Affiliation(s)
- Špela Bavec
- Geological Survey of Slovenia, Dimičeva ulica 14, 1000, Ljubljana, Slovenia.
| | - Mateja Gosar
- Geological Survey of Slovenia, Dimičeva ulica 14, 1000, Ljubljana, Slovenia
| | - Miloš Miler
- Geological Survey of Slovenia, Dimičeva ulica 14, 1000, Ljubljana, Slovenia
| | - Harald Biester
- Technical University Braunschweig, 38106, Brunswick, Germany
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Identification of Potential Sources of Mercury (Hg) in Farmland Soil Using a Decision Tree Method in China. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2016; 13:ijerph13111111. [PMID: 27834884 PMCID: PMC5129321 DOI: 10.3390/ijerph13111111] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/04/2016] [Revised: 11/02/2016] [Accepted: 11/02/2016] [Indexed: 12/07/2022]
Abstract
Identification of the sources of soil mercury (Hg) on the provincial scale is helpful for enacting effective policies to prevent further contamination and take reclamation measurements. The natural and anthropogenic sources and their contributions of Hg in Chinese farmland soil were identified based on a decision tree method. The results showed that the concentrations of Hg in parent materials were most strongly associated with the general spatial distribution pattern of Hg concentration on a provincial scale. The decision tree analysis gained an 89.70% total accuracy in simulating the influence of human activities on the additions of Hg in farmland soil. Human activities—for example, the production of coke, application of fertilizers, discharge of wastewater, discharge of solid waste, and the production of non-ferrous metals—were the main external sources of a large amount of Hg in the farmland soil.
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Windmöller CC, Durão Júnior WA, de Oliveira A, do Valle CM. The redox processes in Hg-contaminated soils from Descoberto (Minas Gerais, Brazil): implications for the mercury cycle. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2015; 112:201-211. [PMID: 25463872 DOI: 10.1016/j.ecoenv.2014.11.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 11/06/2014] [Accepted: 11/11/2014] [Indexed: 06/04/2023]
Abstract
Investigations of the redox process and chemical speciation of Hg(II) lead to a better understanding of biogeochemical processes controlling the transformation of Hg(II) into toxic and bioaccumulative monomethyl mercury, mainly in areas contaminated with Hg(0). This study investigates the speciation and redox processes of Hg in soil samples from a small area contaminated with Hg(0) as a result of gold mining activities in the rural municipality of Descoberto (Minas Gerais, Brazil). Soil samples were prepared by adding Hg(0) and HgCl2 separately to dry soil, and the Hg redox process was monitored using thermodesorption coupled to atomic absorption spectrometry. A portion of the Hg(0) added was volatilized (up to 37.4±2.0%) or oxidized (from 36±7% to 88±16%). A correlation with Mn suggests that this oxidation is favored, but many other factors must be evaluated, such as the presence of microorganisms and the types of organic matter present. The interaction of Hg with the matrix is suggested to involve Hg(II)-complexes formed with inorganic and organic sulfur ligands and/or nonspecific adsorption onto oxides of Fe, Al and/or Mn. The kinetics of the oxidation reaction was approximated for two first-order reactions; the faster reaction was attributed to the oxidation of Hg(0)/Hg(I), and the slower reaction corresponded to Hg(I)/Hg(II). The second stage was 43-139 times slower than the first. The samples spiked with Hg(II) showed low volatilization and a shifting of the signal of Hg(II) to lower temperatures. These results show that the extent, rate and type of redox process can be adverse in soils. Descoberto can serve as an example for areas contaminated with Hg(0).
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Affiliation(s)
- Cláudia C Windmöller
- Departamento de Química, ICEX, UFMG, Av. Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil.
| | | | - Aline de Oliveira
- Departamento de Química, ICEX, UFMG, Av. Antônio Carlos, 6627, 31270-901 Belo Horizonte, MG, Brazil
| | - Cláudia M do Valle
- IFAM-Campus Manaus Centro, Av. Sete de setembro, 1975, 69020-120 Manaus, AM, Brazil
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