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Aslam MW, Meng B, Ali W, Abrar MM, Abdelhafiz MA, Feng X. Low mercury risks in paddy soils across the Pakistan. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 943:173879. [PMID: 38857798 DOI: 10.1016/j.scitotenv.2024.173879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 05/31/2024] [Accepted: 06/07/2024] [Indexed: 06/12/2024]
Abstract
Mercury (Hg) is a globally distributed heavy metal. Here, we study Hg concentration and isotopic composition to understand the status of Hg pollution and its sources in Pakistan's paddy soil. The collected paddy soils (n = 500) across the country have an average THg concentration of 22.30 ± 21.74 ng/g. This low mean concentration suggests Hg pollution in Pakistan was not as severe as previously thought. Meanwhile, samples collected near brick kilns and industrial areas were significantly higher in THg than others, suggesting the influence of Hg emitted from point sources in certain areas. Soil physicochemical properties showed typical characteristic of mineral soils due to the study area's arid to semi-arid climate. Hg stable isotopes analysis, depicted mean Δ199Hg of -0.05 ± 0.12‰ and mean δ202Hg -0.45 ± 0.35‰, respectively, for contaminated sites, depicting Hg was primarily sourced from coal combustion by local anthropogenic sources. While uncontaminated sites show mean Δ199Hg of 0.15 ± 0.08‰, mean Δ200Hg of 0.06 ± 0.07‰ and mean δ202Hg of -0.32 ± 0.28‰, implying long-range transboundry Hg transport through wet Hg(II) deposition as a dominant Hg source. This study fills a significant knowledge gap regarding the Hg pollution status in Pakistan and suggests that the Hg risk in Pakistan paddies is generally low.
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Affiliation(s)
- Muhammad Wajahat Aslam
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China
| | - Bo Meng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China.
| | - Waqar Ali
- Department of Ecological Sciences and Engineering, College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
| | - Muhammad Mohsin Abrar
- College of Resources and Environment, Zhongkai University of Agriculture and Engineering, 510225 Guangzhou, China; Engineering and Technology Research Center for Agricultural Land Pollution and Integrated Prevention, Guangzhou, China
| | - Mahmoud A Abdelhafiz
- Geology Department, Faculty of Science, Al-Azhar University, Assiut 71524, Egypt
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
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Emamverdian A, Khalofah A, Pehlivan N, Li Y, Chen M, Liu G. Iron nanoparticles in combination with other conventional Fe sources remediate mercury toxicity-affected plants and soils by nutrient accumulation in bamboo species. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 278:116431. [PMID: 38718730 DOI: 10.1016/j.ecoenv.2024.116431] [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: 11/14/2023] [Revised: 04/30/2024] [Accepted: 05/03/2024] [Indexed: 05/26/2024]
Abstract
The issue of mercury (Hg) toxicity has recently been identified as a significant environmental concern, with the potential to impede plant growth in forested and agricultural areas. Conversely, recent reports have indicated that Fe, may play a role in alleviating HM toxicity in plants. Therefore, this study's objective is to examine the potential of iron nanoparticles (Fe NPs) and various sources of Fe, particularly iron sulfate (Fe SO4 or Fe S) and iron-ethylene diamine tetra acetic acid (Fe - EDTA or Fe C), either individually or in combination, to mitigate the toxic effects of Hg on Pleioblastus pygmaeus. Involved mechanisms in the reduction of Hg toxicity in one-year bamboo species by Fe NPs, and by various Fe sources were introduced by a controlled greenhouse experiment. While 80 mg/L Hg significantly reduced plant growth and biomass (shoot dry weight (36%), root dry weight (31%), and shoot length (31%) and plant tolerance (34%) in comparison with control treatments, 60 mg/L Fe NPs and conventional sources of Fe increased proline accumulation (32%), antioxidant metabolism (21%), polyamines (114%), photosynthetic pigments (59%), as well as root dry weight (25%), and shoot dry weight (22%), and shoot length (22%). Fe NPs, Fe S, and Fe C in plant systems substantially enhanced tolerance to Hg toxicity (23%). This improvement was attributed to increased leaf-relative water content (39%), enhanced nutrient availability (50%), improved antioxidant capacity (34%), and reduced Hg translocation (6%) and accumulation (31%) in plant organs. Applying Fe NPs alone or in conjunction with a mixture of Fe C and Fe S can most efficiently improve bamboo plants' tolerance to Hg toxicity. The highest efficiency in increasing biochemical and physiological indexes under Hg, was related to the treatments of Fe NPs as well as Fe NPs + FeS + FeC. Thus, Fe NPs and other Fe sources might be effective options to remove toxicity from plants and soil. The future perspective may help establish mechanisms to regulate environmental toxicity and human health progressions.
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Affiliation(s)
- Abolghassem Emamverdian
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China; Bamboo Research Institute, Nanjing Forestry University, Nanjing 210037, China
| | - Ahlam Khalofah
- Biology Department, Faculty of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia; Research Center for Advanced Materials Science (RCAMS), King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia
| | - Necla Pehlivan
- Department of Biology, Recep Tayyip Erdogan University, Rize 53100, Turkiye
| | - Yang Li
- Department of Mathematical Sciences, Florida Atlantic University, Boca Raton, FL 33431, USA
| | - Moxian Chen
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China.
| | - Guohua Liu
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China; Bamboo Research Institute, Nanjing Forestry University, Nanjing 210037, China.
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Gomes PR, Pestana IA, de Almeida MG, de Rezende CE. The Paraíba do Sul River Basin and its coastal area as a study model of the mercury cycle: A meta-analytical review of three decades of research. JOURNAL OF HAZARDOUS MATERIALS 2023; 460:132442. [PMID: 37683351 DOI: 10.1016/j.jhazmat.2023.132442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 08/05/2023] [Accepted: 08/28/2023] [Indexed: 09/10/2023]
Abstract
The Paraíba do Sul River (PSR) Basin is a crucial drainage basin in Southeast Brazil, being the most industrialized and densely populated region in the country. Over the last three decades, the basin has been the subject of numerous studies due to its long history of mercury (Hg) contamination. This makes the PSR Basin an excellent model to evaluate Hg cycling, which is a priority for signatory countries of the Minamata Convention, which includes Brazil. This review compiled data on Hg from five environmental compartments (animals, plants, sediment, suspended particulate matter (SPM), and water), three different sectors (upper, middle, and lower) and five different ecosystems (reservoir, mangrove, fluvial, estuarine, and coastal) from 60 published studies, aiming to understand the Hg cycling through meta-analyses. The highest concentrations of Hg were observed in the upper and middle sectors of the basin, which are areas with high industrialization and urbanization levels. Among the evaluated ecosystems, hydropower reservoirs showed the highest medians and were also frequent in the upper and middle portions of the PSR basin. Over the years, all environmental compartments showed a decline in Hg concentrations due to the implementation of federal and state environmental policies. The main source of Hg for the basin was Hg-rich soils from past activities (such as artisanal small-scale gold mining and the use of organomercurial fungicides in sugarcane plantations). These results can assist decision-makers in the management of the basin's ecosystems and can also be used to evaluate the effectiveness of implementing the Minamata Convention in the region.
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Affiliation(s)
- Philipe Ribeiro Gomes
- Programa de Pós-Graduação em Ecologia e Recursos Naturais, Laboratório de Ciências Ambientais, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Av. Alberto Lamego, 2000 - Parque Califórnia - CEP: 28013-602, Campos dos Goytacazes, Rio de Janeiro, Brazil.
| | - Inácio Abreu Pestana
- Programa de Pós-Graduação em Ecologia e Recursos Naturais, Laboratório de Ciências Ambientais, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Av. Alberto Lamego, 2000 - Parque Califórnia - CEP: 28013-602, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Marcelo Gomes de Almeida
- Programa de Pós-Graduação em Ecologia e Recursos Naturais, Laboratório de Ciências Ambientais, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Av. Alberto Lamego, 2000 - Parque Califórnia - CEP: 28013-602, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Carlos Eduardo de Rezende
- Programa de Pós-Graduação em Ecologia e Recursos Naturais, Laboratório de Ciências Ambientais, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Av. Alberto Lamego, 2000 - Parque Califórnia - CEP: 28013-602, Campos dos Goytacazes, Rio de Janeiro, Brazil
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Chen W, Yu Z, Yang X, Wang T, Li Z, Wen X, He Y, Zhang C. Unveiling the Role of Dissolved Organic Matter on the Hg Phytoavailability in Biochar-Amended Soils. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:3761. [PMID: 36834455 PMCID: PMC9963283 DOI: 10.3390/ijerph20043761] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 02/16/2023] [Accepted: 02/17/2023] [Indexed: 06/13/2023]
Abstract
Biochar can effectively reduce the phytoavailability of mercury (Hg) in soil, but the mechanisms are not fully understood. In this study, the dynamic changes in Hg content adsorbed by the biochar (BC-Hg), Hg phytoavailability in the soil (P-Hg), and soil dissolved organic matter (DOM) characteristics were determined over a 60-day treatment period. Biochar obtained at 300 °C, 500 °C and 700 °C reduced the P-Hg concentration assessed by MgCl2 extraction by 9.4%, 23.5% and 32.7%, respectively. However, biochar showed a very limited adsorption on Hg, with the maximum BC-Hg content only accounting for 1.1% of the total amount. High-resolution scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDS) results showed that the proportion of Hg atoms in biochar after 60 d was barely detectable. Biochar treatment can shift soil DOM toward higher aromatic content and molecular weight. Additionally, the addition of high-temperature biochar increased more humus-like components, but low-temperature biochar increased more protein-like components. Correlation analysis and partial least squares path modeling (PLS-PM) showed that biochar promoted humus-like fractions formation to reduce the Hg phytoavailability. This research has deepened the understanding of the mechanisms by which biochar stabilizes Hg in agricultural soils.
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Affiliation(s)
- Wenhao Chen
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China
- Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China
| | - Zhigang Yu
- Australian Centre for Water and Environmental Biotechnology (Formerly AWMC), The University of Queensland, Brisbane, QLD 4072, Australia
| | - Xu Yang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China
- Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China
| | - Tantan Wang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China
- Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China
| | - Zihao Li
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China
- Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China
| | - Xin Wen
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China
- Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China
| | - Yubo He
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China
- Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China
| | - Chang Zhang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China
- Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China
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Lima FRD, Pereira P, Silva Junior EC, Vasques ICF, Oliveira JR, Windmöller CC, Inda AV, Weindorf DC, Curi N, Ribeiro BT, Guilherme LRG, Marques JJ. Geochemistry signatures of mercury in soils of the Amazon rainforest biome. ENVIRONMENTAL RESEARCH 2022; 215:114147. [PMID: 36063907 DOI: 10.1016/j.envres.2022.114147] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 08/13/2022] [Accepted: 08/16/2022] [Indexed: 06/15/2023]
Abstract
Mercury (Hg) toxicity in soils depends on Hg species and other physical and chemical attributes, as selenium (Se) hotspots in soils, particularly relevant in Amazonian soils. The study of Hg species and their relations in representative locations of the Amazon rainforest biome is critical for assessing the potential risks of Hg in this environment. This work aimed to determine the concentration of total Hg and its species (Hg0, Hg22+ and Hg2+), and to correlate Hgtotal concentration with total elemental composition, magnetic susceptibility, and physicochemical attributes of Amazon soils. Nine sites in the Amazon rainforest biome, Brazil, were selected and analyzed for their chemical, physical, and mineralogical attributes. The clay fraction of the studied Amazon soils is dominated by kaolinite, goethite, hematite, gibbsite, and quartz. Mica was also found in soils from the States of Acre and Amazonas. Hgtotal ranged from 21.5 to 208 μg kg-1 (median = 104 μg kg-1), and the concentrations did not exceed the threshold value established for Brazilian soils (500 μg kg-1). The Hg2+ was notably the predominant species. Its occurrence and concentration were correlated with the landscape position and soil attributes. Hgtotal was moderately and positively correlated with TiO2, clay, and Se. The findings showed that geographic location, geological formation, and pedological differences influence the heterogeneity and distribution of Hgtotal in the studied soil classes. Thus, a detailed characterization and knowledgment of the soil classes is very important to clarify the complex behavior of this metal in the Amazon rainforest biome.
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Affiliation(s)
- Francielle R D Lima
- Department of Soil Science, Federal University of Lavras, Lavras, MG, Brazil
| | - Polyana Pereira
- Department of Soil Science, Federal University of Lavras, Lavras, MG, Brazil
| | - Ediu C Silva Junior
- Department of Soil Science, Federal University of Lavras, Lavras, MG, Brazil
| | - Isabela C F Vasques
- Soil and Plant Nutrition Department, Federal University of Viçosa, Viçosa, MG, Brazil
| | - Jakeline R Oliveira
- Department of Soil Science, Federal University of Lavras, Lavras, MG, Brazil
| | - Cláudia C Windmöller
- Department of Chemistry, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Alberto V Inda
- Department of Soils, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - David C Weindorf
- Department of Earth and Atmospheric Sciences, Central Michigan University, Mount Pleasant, MI, USA
| | - Nilton Curi
- Department of Soil Science, Federal University of Lavras, Lavras, MG, Brazil
| | - Bruno T Ribeiro
- Department of Soil Science, Federal University of Lavras, Lavras, MG, Brazil
| | - Luiz R G Guilherme
- Department of Soil Science, Federal University of Lavras, Lavras, MG, Brazil
| | - João José Marques
- Department of Soil Science, Federal University of Lavras, Lavras, MG, Brazil.
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Wen M, Ma Z, Gingerich DB, Zhao X, Zhao D. Heavy metals in agricultural soil in China: A systematic review and meta-analysis. ECO-ENVIRONMENT & HEALTH 2022; 1:219-228. [PMID: 38077260 PMCID: PMC10702913 DOI: 10.1016/j.eehl.2022.10.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 10/03/2022] [Accepted: 10/15/2022] [Indexed: 05/27/2024]
Abstract
Research about farmland pollution by heavy metals/metalloids in China has drawn growing attention. However, there was rare information on spatiotemporal evolution and pollution levels of heavy metals in the major grain-producing areas. We extracted and examined data from 276 publications between 2010 and 2021 covering five major grain-producing regions in China from 2010 to 2021. Spatiotemporal evolution characteristics of main heavy metals/metalloids was obtained by meta-analysis. In addition, subgroup analyses were carried out to study preliminary correlations related to accumulation of the pollutants. Cadmium (Cd) was found to be the most prevailing pollutant in the regions in terms of both spatial distribution and temporal accumulation. The Huang-Huai-Hai Plain was the most severely polluted. Accumulation of Cd, mercury (Hg) and copper (Cu) increased from 2010 to 2015 when compared with the 1990 background data. Further, the levels of five key heavy metals (Cd, Cu, Hg, lead [Pb] and zinc [Zn]) showed increasing trends from 2016 to 2021 in all five regions. Soil pH and mean annual precipitation had variable influences on heavy metal accumulation. Alkaline soil and areas with less rainfall faced higher pollution levels. Farmlands cropped with mixed species showed smaller effect sizes of heavy metals than those with single upland crop, suggesting that mixed farmland use patterns could alleviate the levels of heavy metals in soil. Of various soil remediation efforts, farmland projects only held a small market share. The findings are important to support the research of risk assessment, regulatory development, pollution prevention, fund allocation and remediation actions.
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Affiliation(s)
- Moyan Wen
- College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China
| | - Ziqi Ma
- College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China
| | - Daniel B. Gingerich
- Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, Columbus, OH 43210, USA
- Department of Integrated Systems Engineering, The Ohio State University, Columbus, OH 43210, USA
| | - Xiao Zhao
- College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China
| | - Dongye Zhao
- Environmental Engineering Program, Department of Civil Engineering, Auburn University, Auburn, AL 36849, USA
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Yin D, Zhou X, He T, Wu P, Ran S. Remediation of Mercury-Polluted Farmland Soils: A Review. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2022; 109:661-670. [PMID: 35690951 DOI: 10.1007/s00128-022-03544-0] [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: 12/26/2021] [Accepted: 05/09/2022] [Indexed: 06/15/2023]
Abstract
Mercury (Hg) bioaccumulation in Hg-polluted farmlands poses high health risk for humans and wildlife, and remediation work is urgently needed. Here, we first summarize some specific findings related to the environmental process of Hg in Hg-polluted farmlands, and distinguish the main achievements and deficiencies of available remediation strategies in recent studies. Results demonstrate that farmland is a sensitive area with vibrant Hg biogeochemistry. Current remediation methods are relatively hysteretic whether in mechanism understanding or field application, and deficient for large-scale Hg-polluted farmlands in view of safety, efficiency, sustainability, and cost-effectiveness. New perspectives including environment-friendly functional materials, assisted phytoremediation and agronomic regulations are worthy of further study as their key roles in reducing Hg exposure risk and protecting agricultural sustainability.
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Affiliation(s)
- Deliang Yin
- Key Laboratory of Karst Georesources and Environment, Ministry of Education, College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China
| | - Xian Zhou
- Key Laboratory of Karst Georesources and Environment, Ministry of Education, College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China
| | - Tianrong He
- Key Laboratory of Karst Georesources and Environment, Ministry of Education, College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China
| | - Pan Wu
- Key Laboratory of Karst Georesources and Environment, Ministry of Education, College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China.
| | - Shu Ran
- Key Laboratory of Karst Georesources and Environment, Ministry of Education, College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China
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Mercury Pollution from Artisanal and Small-Scale Gold Mining in Myanmar and Other Southeast Asian Countries. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19106290. [PMID: 35627826 PMCID: PMC9142007 DOI: 10.3390/ijerph19106290] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/15/2022] [Accepted: 05/16/2022] [Indexed: 02/04/2023]
Abstract
Mercury (Hg) is one of the most harmful metals and has been a public health concern according to the World Health Organization (WHO). Artisanal and small-scale gold mining (ASGM) is the world’s fastest-growing source of Hg and can release Hg into the atmosphere, hydrosphere, and geosphere. Hg has been widely used in ASGM industries throughout Southeast Asia countries, including Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, and Thailand. Here, 16 relevant studies were systematically searched by performing the PRISMA flow, combining the keywords of “Hg”, “ASGM”, and relevant study areas. Mercury concentrations exceeding the WHO and United States Environmental Protection Agency guideline values were reported in environmental (i.e., air, water, and soil) and biomonitoring samples (i.e., plants, fish, and human hair). ASGM-related health risks to miners and nonminers, specifically in Indonesia, the Philippines, and Myanmar, were also assessed. The findings indicated severe Hg contamination around the ASGM process, specifically the gold-amalgamation stage, was significantly high. To one point, Hg atmospheric concentrations from all observed studies was shown to be extremely high in the vicinity of gold operating areas. Attentions should be given regarding the public health concern, specifically for the vulnerable groups such as adults, pregnant women, and children who live near the ASGM activity. This review summarizes the effects of Hg in Myanmar and other Southeast Asian countries. In the future, more research and assessment will be required to investigate the current and evolving situation in ASGM communities.
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Shen Z, Zhang Z, Zhang M, Rinklebe J, Ma Y, Hou D. Effect of production temperature and particle size of rice husk biochar on mercury immobilization and erosion prevention of a mercury contaminated soil. JOURNAL OF HAZARDOUS MATERIALS 2021; 420:126646. [PMID: 34329115 DOI: 10.1016/j.jhazmat.2021.126646] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 06/24/2021] [Accepted: 07/09/2021] [Indexed: 06/13/2023]
Abstract
Mercury (Hg) contaminated soil is a potential hazardous material especially under soil erosion and surface runoff. This work aims to use rice husk biochar to immobilize Hg and prevent erosion, and find the optimal production temperature and particle size of the biochar. The biochars were produced at 300, 500, and 700 °C and sieved to three particle sizes ~20, < 2, and < 0.15 mm. They were applied to a Hg contaminated loamy sand (20.2 mg/kg) and undergone simulated rainfall erosion representing 7 years of heavy rain events in Beijing. All biochar amendments reduced the runoff volume by 5.1-15.4%. Hg amount in runoff were significantly reduced by 36.7-48.8% after the amendments of biochar. The Hg concentration of infiltration was reduced by biochar treatments except that produced at 300 °C, while its amount was increased due to larger infiltration volume. All biochar amendments significantly reduced soil loss in runoff by 43.5-77.2%. Hg was enriched in the sediments (39.7-46.8 mg/kg) compared with the parent soil (20.2 mg/kg) regardless of biochar treatment, but its bioavailability was low. Higher pyrolysis temperature of the rice husk biochars resulted in less runoff, more infiltration, and better erosion prevention, while the effect of biochar particle size is less significant.
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Affiliation(s)
- Zhengtao Shen
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Zhuorong Zhang
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Mengdi Zhang
- School of Environment, Tsinghua University, Beijing 100084, China; School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing 100083, China
| | - Jörg Rinklebe
- University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water and Waste Management, Laboratory of Soil and Groundwater Management, Pauluskirchstraße 7, 42285 Wuppertal, Germany; Department of Environment, Energy and Geoinformatics, Sejong University, 98 Gunja-Dong, Guangjin-Gu, Seoul, Republic of Korea
| | - Yan Ma
- School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing 100083, China
| | - Deyi Hou
- School of Environment, Tsinghua University, Beijing 100084, China.
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Zou M, Zhou S, Zhou Y, Jia Z, Guo T, Wang J. Cadmium pollution of soil-rice ecosystems in rice cultivation dominated regions in China: A review. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 280:116965. [PMID: 33774546 DOI: 10.1016/j.envpol.2021.116965] [Citation(s) in RCA: 108] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 03/14/2021] [Accepted: 03/15/2021] [Indexed: 05/22/2023]
Abstract
Cd accumulation in paddy soils and its subsequent transfer to the food chain are widespread environmental issues, which has been extensively investigated in China. However, most studies focused on regional scales and these results may not be applicable to present the Cd contamination status in soil-rice ecosystems at a national scale. Therefore, based on collected data from China's rice cultivation dominated regions, this study provides the Cd pollution level of paddy soils and rice grains in China. Results indicates that the Yangtze River basin, especially Hunan, required more attention due to the elevated Cd concentrations in soil-rice ecosystems. Moreover, this review summarizes the significant natural and anthropogenic sources, transport and accumulation mechanism as well as the influencing factors of Cd in soil-rice ecosystems. The wide occurrence of Cd contamination in paddy soils derived primarily from mining activities, intensive application of phosphates fertilizers and e-waste. Physicochemical characteristics of soil, soil microorganisms, temperature as well as the physiological features of rice plants all contribute to Cd accumulation in rice grains, which can be controlled to mitigate Cd accumulation in rice grains. This review will provide a scientific reference for Cd pollution control and management with respect to paddy field ecosystems in China and other countries.
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Affiliation(s)
- Mengmeng Zou
- School of Geography and Ocean Science, Nanjing University, Nanjing, 210023, China; Key Laboratory of Coastal Zone Exploitation and Protection, Ministry of Natural Resources, Nanjing, 210024, China
| | - Shenglu Zhou
- School of Geography and Ocean Science, Nanjing University, Nanjing, 210023, China; Key Laboratory of Coastal Zone Exploitation and Protection, Ministry of Natural Resources, Nanjing, 210024, China.
| | - Yujie Zhou
- School of Geography and Ocean Science, Nanjing University, Nanjing, 210023, China; Key Laboratory of Coastal Zone Exploitation and Protection, Ministry of Natural Resources, Nanjing, 210024, China
| | - Zhenyi Jia
- School of Geography and Ocean Science, Nanjing University, Nanjing, 210023, China; Key Laboratory of Coastal Zone Exploitation and Protection, Ministry of Natural Resources, Nanjing, 210024, China
| | - Tianwei Guo
- School of Geography and Ocean Science, Nanjing University, Nanjing, 210023, China; Key Laboratory of Coastal Zone Exploitation and Protection, Ministry of Natural Resources, Nanjing, 210024, China
| | - Junxiao Wang
- School of Geography and Ocean Science, Nanjing University, Nanjing, 210023, China; Key Laboratory of Coastal Zone Exploitation and Protection, Ministry of Natural Resources, Nanjing, 210024, China
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Addai-Arhin S, Novirsa R, Jeong HH, Phan QD, Hirota N, Ishibashi Y, Shiratsuchi H, Arizono K. The human health risks assessment of mercury in soils and plantains from farms in selected artisanal and small-scale gold mining communities around Obuasi, Ghana. J Appl Toxicol 2021; 42:258-273. [PMID: 34133775 DOI: 10.1002/jat.4209] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 05/19/2021] [Accepted: 05/25/2021] [Indexed: 11/08/2022]
Abstract
Food consumption remains the commonest pathway through which humans ingest higher levels of mercury (Hg). Long-term exposure to Hg through Hg-contaminated food may result in acute or chronic Hg toxicity. Incessant discharge of Hg waste from ASGM facilities into nearby farms contaminates food crops. Ingestion of such food crops by residents may lead to detrimental human health effects. The human health risks upon exposure to total mercury (THg) and methylmercury (MeHg) in farmland soils and plantains from farms sited near ASGM facilities were studied in four communities around Obuasi, Ghana. The human health risk assessment was evaluated using hazard quotient (HQ), estimated average daily intake (e AvDI), hazard index (HI) and Hg elimination and retention kinetics. Tweapease, Nyamebekyere and Ahansonyewodea had HQ, e AvDI and HI for THg of plantains for both adults and children below the recommended USEPA limit of 1, 3 × 10-4 mg/kg/day and 1, respectively. Odumase had HQ, e AvDI and HI for THg of plantains for both adults and children, higher than the guideline values. This meant that only Odumase may cause non-carcinogenic human health effects upon repeated exposure. The HQ, e AvDI and HI values of MeHg for all the study areas were far below guideline values, hence may not pose any non-carcinogenic human health risks to residents even upon repeated exposure. Retention and elimination kinetics of Hg also showed that only plantains from Odumase may pose significant non-carcinogenic human health risks to residents because the final amount of inorganic mercury exceeded the extrapolated USEPA guideline value of 0.393 μg/kg/year.
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Affiliation(s)
- Sylvester Addai-Arhin
- Graduate School of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan.,Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan.,Pharmaceutical Science Department, Faculty of Health Sciences, Kumasi Technical University, Kumasi, Ghana
| | - Randy Novirsa
- Graduate School of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan.,Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan
| | - Hui Ho Jeong
- Graduate School of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan.,Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan
| | - Quang Dinh Phan
- Graduate School of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan.,Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan
| | - Nana Hirota
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan
| | - Yasuhiro Ishibashi
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan
| | - Hideki Shiratsuchi
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan
| | - Koji Arizono
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan.,Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan
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12
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Wang P, Peng H, Liu J, Zhu Z, Bi X, Yu Q, Zhang J. Effects of exogenous dissolved organic matter on the adsorption-desorption behaviors and bioavailabilities of Cd and Hg in a plant-soil system. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 728:138252. [PMID: 32335403 DOI: 10.1016/j.scitotenv.2020.138252] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 03/25/2020] [Accepted: 03/25/2020] [Indexed: 06/11/2023]
Abstract
Dissolved organic matter (DOM) is one of the most active soil components and plays critical direct and indirect roles in heavy metal migration, transformation, bioavailability, and toxicity in soils. In this study, isothermal adsorption/desorption experiments and pot experiments were performed and samples were physically characterized to study the effects of different sources of DOM on adsorption and desorption behavior and bioavailability of Cd and Hg in a plant-soil system. The results showed that microbial DOM promoted Cd and Hg adsorption in soil and decreased Cd and Hg bioavailability to pak choi (Brassica chinensis Linn.). In contrast, straw DOM and farmyard manure DOM decreased Cd and Hg adsorption and improved Cd and Hg migration and bioavailability. These results might be explained by the different types of DOM having different molecular weights and degrees of aromaticity. Cd was more readily desorbed by the soil and was more phytoavailable than Hg. We concluded that exogenous microbial DOM can inhibit Cd and Hg migration and bioavailability in soil but straw DOM and farmyard manure DOM can activate Cd and Hg in soil and promote Cd and Hg accumulation in plants. The results could help in developing rational agricultural fertilization regimes.
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Affiliation(s)
- Pengcong Wang
- Hubei Key Laboratory of Critical Zone Evolution, School of Earth Sciences, China University of Geosciences, Wuhan 430074, China
| | - Huan Peng
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China
| | - Jinling Liu
- Hubei Key Laboratory of Critical Zone Evolution, School of Earth Sciences, China University of Geosciences, Wuhan 430074, China.
| | - Zhenli Zhu
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China
| | - Xiangyang Bi
- Hubei Key Laboratory of Critical Zone Evolution, School of Earth Sciences, China University of Geosciences, Wuhan 430074, China; State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China
| | - Qianqian Yu
- Hubei Key Laboratory of Critical Zone Evolution, School of Earth Sciences, China University of Geosciences, Wuhan 430074, China
| | - Jie Zhang
- Institute of Mathematical Geology & Remote Sensing, China University of Geoscience, Wuhan 430074, China
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13
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Zeng S, Ma J, Yang Y, Zhang S, Liu GJ, Chen F. Spatial assessment of farmland soil pollution and its potential human health risks in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 687:642-653. [PMID: 31220718 DOI: 10.1016/j.scitotenv.2019.05.291] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 05/17/2019] [Accepted: 05/20/2019] [Indexed: 05/15/2023]
Abstract
Soil pollution severely threatens agro-ecosystem stability. It is important to accurately understand the status of farmland pollution in order to protect national food safety and human health. However, information of the combined pollution level of Chinese farmland soil and associated human health risk at the national scale is relatively lacking. In this study, 5597 samples from 1781 farmland soil sites were obtained from 553 reports and combined into pollution databases of heavy metals, organochlorines, and polycyclic aromatic hydrocarbons. Based on the data obtained, this paper demonstrated the current pollution status of farmland soil, and assessed the subsequent human health risk. Results showed that the combined pollution ratio of Chinese farmland soil was 22.10%, with 1.23% of severe pollution level. Moreover, the total non-carcinogenic hazard quotients of farmland soil pollution were within the safety threshold for adults, but there was a slight non-carcinogenic risk for children. For adults, the ratio of total farmland area to total carcinogenic risk quotients above the safety threshold of 1 × 10-5 was only 1.02%, but for children, the ratio was as high as 20.75%. On the other side, food crop and vegetable plantations were the priority control farmland soil compared to other types. Meanwhile, Yunnan, Hunan, Anhui, Henan, and Liaoning were selected as the priority control provinces due to their severe pollutions and high human health risks. This study has provided a comprehensive pollution and health risk assessment. Furthermore, the spatial distribution might provide as the scientific support for accelerating the mapping of soil pollution in China, as well as developing the policy for the contaminated farmland soil management.
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Affiliation(s)
- Siyan Zeng
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou, Jiangsu 221008, China
| | - Jing Ma
- Low Carbon Energy Institute, China University of Mining and Technology, Xuzhou, Jiangsu 221008, China
| | - Yongjun Yang
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou, Jiangsu 221008, China
| | - Shaoliang Zhang
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou, Jiangsu 221008, China
| | - Gang-Jun Liu
- Geospatial Sciences, College of Science, Engineering, and Health, RMIT University, Melbourne 3000, Australia
| | - Fu Chen
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou, Jiangsu 221008, China; Low Carbon Energy Institute, China University of Mining and Technology, Xuzhou, Jiangsu 221008, China.
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14
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Raj D, Maiti SK. Sources, toxicity, and remediation of mercury: an essence review. ENVIRONMENTAL MONITORING AND ASSESSMENT 2019; 191:566. [PMID: 31418123 DOI: 10.1007/s10661-019-7743-2] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 08/06/2019] [Indexed: 05/27/2023]
Abstract
Mercury (Hg) is a pollutant that poses a global threat, and it was listed as one of the ten leading 'chemicals of concern' by the World Health Organization in 2017. The review aims to summarize the sources of Hg, its combined effects on the ecosystem, and its remediation in the environment. The flow of Hg from coal to fly ash (FA), soil, and plants has become a serious concern. Hg chemically binds to sulphur-containing components in coal during coal formation. Coal combustion in thermal power plants is the major anthropogenic source of Hg in the environment. Hg is taken up by plant roots from contaminated soil and transferred to the stem and aerial parts. Through bioaccumulation in the plant system, Hg moves into the food chain, resulting in potential health and ecological risks. The world average Hg concentrations reported in coal and FA are 0.01-1 and 0.62 mg/kg, respectively. The mass of Hg accumulated globally in the soil is estimated to be 250-1000 Gg. Several techniques have been applied to remove or minimize elevated levels of Hg from FA, soil, and water (soil washing, selective catalytic reduction, wet flue gas desulphurization, stabilization, adsorption, thermal treatment, electro-remediation, and phytoremediation). Adsorbents such as activated carbon and carbon nanotubes have been used for Hg removal. The application of phytoremediation techniques has been proven as a promising approach in the removal of Hg from contaminated soil. Plant species such as Brassica juncea are potential candidates for Hg removal from soil.
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Affiliation(s)
- Deep Raj
- Ecological Restoration Laboratory, Department of Environmental Science & Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad, Jharkhand, 826 004, India
| | - Subodh Kumar Maiti
- Ecological Restoration Laboratory, Department of Environmental Science & Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad, Jharkhand, 826 004, India.
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15
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Liu J, Wang J, Ning Y, Yang S, Wang P, Shaheen SM, Feng X, Rinklebe J. Methylmercury production in a paddy soil and its uptake by rice plants as affected by different geochemical mercury pools. ENVIRONMENT INTERNATIONAL 2019; 129:461-469. [PMID: 31154148 DOI: 10.1016/j.envint.2019.04.068] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 04/15/2019] [Accepted: 04/28/2019] [Indexed: 06/09/2023]
Abstract
The formation of neurotoxic methylmercury (MeHg) in paddy fields and its accumulation by rice plants is of high environmental concern. The contribution of different geochemical mercury (Hg) pools in paddy soils to MeHg production and its accumulation by rice seedlings is not well-studied up to now. Therefore, we investigated the impact of different inorganic Hg forms, including HgCl2, nano-particulated HgS (nano-HgS), Hg bound with dissolved organic matter (Hg-DOM), β-HgS, and α-HgS, at levels of 5 mg Hg/kg soil and 50 mg Hg/kg soil, on the production of MeHg in the soil during rice growing season. Further, we studied the uptake of MeHg by the roots, stalks, leaves, and grains of rice in the tillering, panicle formation, and ripening growth stages, and compared these treatments to a non-polluted soil (control). MeHg contents in HgCl2 polluted soil were the highest, and were 13.5 times and 36.1 times higher than control in 5 and 50 mg/kg Hg treatments, respectively. MeHg contents in α-HgS, β-HgS, nano-HgS, and Hg-DOM polluted soil were 3.9, 2.6, 2.4, and 1.7 times, and 4.4, 15.1, 6.7, and 10.9 times higher than control in 5 and 50 mg/kg Hg treatments, respectively, suggesting the mobilization and methylation of these Hg complexes. The ratio of MeHg to total Hg in the pore water (indication of methylation potential) in HgCl2 and β-HgS treatments were higher than in Hg-DOM, α-HgS, and nano-HgS treatments. HgCl2 treatment resulted in significantly higher MeHg contents in the root, stalk, leaf, and brown rice than nano-HgS, Hg-DOM, β-HgS, and α-HgS treatments both in 5 and 50 mg/kg Hg polluted soils. Rice grain in HgCl2 treatment showed a potential hazard to human health, as indicated by high health risk index (HRI > 1) of MeHg. Current results improve our understanding of MeHg production in soil polluted with different Hg forms, and the assessment of human health risks from consumption of MeHg-laden rice grain at Hg polluted sites with different Hg forms in soils.
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Affiliation(s)
- Jinling Liu
- School of Earth Sciences, China University of Geosciences, Wuhan 430074, China.
| | - Jianxu Wang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water- and Waste-Management, Laboratory of Soil- and Groundwater-Management, Pauluskirchstraße 7, 42285 Wuppertal, Germany; CAS Center for Excellence in Quaternary Science and Global Change, Xi'an 710061, China.
| | - Yongqiang Ning
- School of Earth Sciences, China University of Geosciences, Wuhan 430074, China
| | - Shaochen Yang
- School of Earth Sciences, China University of Geosciences, Wuhan 430074, China
| | - Pengcong Wang
- School of Earth Sciences, China University of Geosciences, Wuhan 430074, China
| | - Sabry M Shaheen
- University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water- and Waste-Management, Laboratory of Soil- and Groundwater-Management, Pauluskirchstraße 7, 42285 Wuppertal, Germany; King Abdulaziz University, Faculty of Meteorology, Environment, and Arid Land Agriculture, Department of Arid Land Agriculture, 21589 Jeddah, Saudi Arabia; University of Kafrelsheikh, Faculty of Agriculture, Department of Soil and Water Sciences, 33516 Kafr El-Sheikh, Egypt.
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Jörg Rinklebe
- University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water- and Waste-Management, Laboratory of Soil- and Groundwater-Management, Pauluskirchstraße 7, 42285 Wuppertal, Germany; University of Sejong, Department of Environment, Energy and Geoinformatics, 98 Gunja-Dong, Guangjin-Gu, Seoul, South Korea.
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16
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Konkina IG, Ivanov SP, Murinov YI. Binuclear Mercury(I) Complex with D-Gluconic Acid. RUSS J INORG CHEM+ 2019. [DOI: 10.1134/s0036023619020116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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17
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Huang Y, Wang L, Wang W, Li T, He Z, Yang X. Current status of agricultural soil pollution by heavy metals in China: A meta-analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 651:3034-3042. [PMID: 30463153 DOI: 10.1016/j.scitotenv.2018.10.185] [Citation(s) in RCA: 265] [Impact Index Per Article: 53.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 10/12/2018] [Accepted: 10/13/2018] [Indexed: 06/09/2023]
Abstract
In the last decades, agricultural soil pollution by heavy metals has been extensively investigated in China. However, nearly all studies were field monitoring in small regions and/or with limited samples, which may not represent soil pollution situation at the national scale. In this paper, attempt was made to provide a comprehensive report about heavy metal pollution in China based on meta-analysis of reviewed data. Given the characteristics of field monitoring studies, the weighted mean values based on "sampling number", "study area", and "standard deviation" were calculated to represent national mean values. In addition, subgroup analysis and cumulative meta-analysis were applied to explore the spatial and temporal variations as well as the influence of cropping systems. 336 articles published from 2005 to 2017 were reviewed in the analysis. Eight heavy metals (cadmium (Cd), chromium (Cr), mercury (Hg), lead (Pb), arsenic (As), copper (Cu), zinc (Zn) and nickel (Ni)) were analyzed. The contents of Cd and Hg were increased compared to background values, while, other six elements showed no significant accumulation. Little pollution was found in normal farmland, which was far from obvious anthropogenic emissions, but Cd and Hg in mining & smelting areas and industrial areas continued to accumulate significantly. Moreover, the accumulation had slowed down or decreased since 2012, which might be due to reduced use of coals, non-ferrous metals and agro-chemicals. Heavy metal contents were generally higher in southwest and south coastal areas but lower in northwest regions, whereas vegetable and paddy fields had higher concentrations than upland and other land use. This study provides information on soil pollution caused by heavy metals and its affected regions and cropping systems on a national scale. It can be useful for developing heavy metal pollution control and management strategies in China.
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Affiliation(s)
- Ying Huang
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China.
| | - Lingyu Wang
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wenjia Wang
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Tingqiang Li
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Zhenli He
- Indian River Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Fort Pierce, FL 34945, USA
| | - Xiaoe Yang
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
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18
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Wang J, Anderson CWN, Xing Y, Fan Y, Xia J, Shaheen SM, Rinklebe J, Feng X. Thiosulphate-induced phytoextraction of mercury in Brassica juncea: Spectroscopic investigations to define a mechanism for Hg uptake. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 242:986-993. [PMID: 30373044 DOI: 10.1016/j.envpol.2018.07.065] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 07/12/2018] [Accepted: 07/15/2018] [Indexed: 06/08/2023]
Abstract
Thiosulphate is extensively used to enhance mercury (Hg) phytoextraction due to its efficient in prompting plant Hg uptake. However, the mechanism by which thiosulphate promotes Hg uptake is poorly understood. We determined the concentrations of Hg and potassium (K), and their spatial distribution, in the tissues of Brassica juncea grown in Hg-contaminated soils treated by thiosulphate and compared this to a non-treated soil (control). The spatial distribution of Hg and K was characterized using micro-X ray fluorescence spectroscopy. The subcellular localization and speciation of Hg in the root of plant treated by thiosulphate were elucidated using Transmission electron microscope coupled energy-dispersive X-ray (TEM-EDX) spectroscopy. Thiosulphate increased significantly the Hg concentration in the roots (mainly in the epidermis and xylem) and shoots (mainly in the vascular bundles), while Hg was accumulated in the root (mainly in the epidermis) of the control plant. Thiosulphate promoted the movement of Hg from the epidermis to the xylem of roots, with subsequent loading into the stem via vascular bundles. Thiosulphate decreased the K concentration in plant tissues, relative to the control plant, and we propose this is due to leakage of electrolyte from roots via increased plasma membrane permeability as a consequence of physiological damage caused by the added thiosulphate. Mercury was distributed mainly at the extracellular space in the roots and was shown by TEM-EDX to be predominately amorphous nano-clusters of HgS. We conclude that thiosulphate-promoted Hg accumulation in the plant may happen through increased plasma membrane permeability, a changed pathway of Hg movement within plants, and extracellular co-transportation of Hg-S complexes in the roots. Our results may underpin the ongoing development of phytomanagement as an environmental strategy for Hg contaminated soils around the world.
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Affiliation(s)
- Jianxu Wang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 550082, Guiyang, PR China; University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water- and Waste-Management, Laboratory of Soil- and Groundwater-Management, Pauluskirchstraße 7, 42285, Wuppertal, Germany.
| | - Christopher W N Anderson
- Environmental Sciences, School of Agriculture and Environment, Massey University, 4442, Palmerston North, New Zealand.
| | - Ying Xing
- School of Chemistry and Materials Science, Guizhou Normal University, 550002, Guiyang, China
| | - Yuhong Fan
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 550082, Guiyang, PR China
| | - Jicheng Xia
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 550082, Guiyang, PR China; University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Sabry M Shaheen
- University of Kafrelsheikh, Faculty of Agriculture, Department of Soil and Water Sciences, 33516, Kafr El-Sheikh, Egypt; University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water- and Waste-Management, Laboratory of Soil- and Groundwater-Management, Pauluskirchstraße 7, 42285, Wuppertal, Germany.
| | - Jörg Rinklebe
- University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water- and Waste-Management, Laboratory of Soil- and Groundwater-Management, Pauluskirchstraße 7, 42285, Wuppertal, Germany; University of Sejong, Department of Environment, Energy and Geoinformatics, 98 Gunja-Dong, Guangjin-Gu, Seoul, Republic of Korea.
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 550082, Guiyang, PR China.
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Sodango TH, Li X, Sha J, Bao Z. Review of the Spatial Distribution, Source and Extent of Heavy Metal Pollution of Soil in China: Impacts and Mitigation Approaches. J Health Pollut 2018; 8:53-70. [PMID: 30524849 PMCID: PMC6221442 DOI: 10.5696/2156-9614-8.17.53] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Accepted: 11/07/2017] [Indexed: 04/23/2023]
Abstract
BACKGROUND China has undergone a rapid industrial revolution and urbanization during the past three decades. This expansion is largely responsible for the release of a large amount of heavy metals into soils and is increasingly raising concerns over the potential effects on human health and the environment. The problem is drawing increasing attention, especially after an extensive nationwide soil survey report in 2014. A number of studies have examined soil contamination by heavy metals in China. However, most of these studies have been small in scale and it is therefore challenging to get a general overview of the level of contamination across the entire country. OBJECTIVES The present study is aimed at presenting a synthesized overview of the extent, pattern, and impact of heavy metal contamination of soils in China, including mitigation approaches. METHODS Eighty-six journal articles and other literature such as reports, internet sources, and statistical yearbooks were narratively and critically synthesized to compile a holistic summary of sources of heavy metals, the extent of pollution, spatial distribution and impact of heavy metal contamination in China. The major findings from these studies are presented, along with mitigation approaches applicable to China. DISCUSSION A synthesis of major findings from recent scientific journals shows that about 10.18% of farmland soils which supports 13.86% of grain production in China is affected by heavy metals. The main sources of pollution are anthropogenic activities. Even though the spatial distribution of pollution is highly variable owing to natural and human factors, provinces with intensive industrial activities such as Henan, Shandong, and Sichuan are more highly polluted than others. These regions are top grain producing areas and hence require close follow-up for development of feasible approaches to mitigating crop contamination and associated health risks emerging in parts of China. The government recently launched a program aimed at determining sound reclamation strategies. CONCLUSION Mitigation of heavy metal contamination in China requires coordination of different actors and integration of all feasible reclamation approaches. COMPETING INTERESTS The authors declare no competing financial interests.
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Affiliation(s)
- Terefe Hanchiso Sodango
- Fujian Normal University, College of Geographical Sciences, State Key Laboratory of Mountain Ecology, Department of GIS and Cartography, Fuzhou, China
| | - Xiaomei Li
- Fujian Normal University, College of Environmental Science and Engineering, Fuzhou, China
| | - Jinming Sha
- Fujian Normal University, College of Geographical Sciences, State Key Laboratory of Mountain Ecology, Department of GIS and Cartography, Fuzhou, China
| | - Zhongcong Bao
- Fujian Normal University, College of Geographical Sciences, State Key Laboratory of Mountain Ecology, Department of GIS and Cartography, Fuzhou, China
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