1
|
Fang F, Ding L, Zhang Y, Qiao X, Qian L, Wei R, Chen H, Ji H, Pi B, Wong MH, Tao H, Xu N, Zhang L. Bacterial mercury methylation modulated by vitamin B9: An overlooked pathway leads to increased environmental risks. JOURNAL OF HAZARDOUS MATERIALS 2024; 479:135625. [PMID: 39191012 DOI: 10.1016/j.jhazmat.2024.135625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2024] [Revised: 08/06/2024] [Accepted: 08/21/2024] [Indexed: 08/29/2024]
Abstract
There has been a serious health and environmental concern in conversion of inorganic mercury (Hg) to the neurotoxin, methylmercury (MeHg) by anaerobic microbes, while very little is known about the potential role of vitamin B9 (VB9) regulator in the biochemical generation of MeHg. This study innovatively investigated bacterial Hg methylation by Geobacter sulfurreducens PCA in the presence of VB9 under two existing scenarios. In the low-complexing scenario, the bacterial MeHg yield reached 68 % higher than that without VB9 within 72 h, which was attributed to free VB9-protected PCA cells relieving oxidative stress, as manifested by the increased expression of Hg methylation gene (hgcAB cluster by 19-48 %). The high-complexing scenario emphasized the intracellular Hg accumulation (38-45 %) after 12 h, as indicated by the increased expression of outer membrane protein-related and mercuric reductase-encoding genes, indicating the inefficient bioavailability of Hg due to a gradual shift from Hg reduction toward Hg0 re-oxidation controlled by competitive ligand exchange. These results suggested that VB9 application significantly raised the potential for bacterial Hg methylation and cellular accumulation, thus proposing insights into the biochemical behaviors of hazardous Hg in farming environments where vulnerable organisms are more possibly co-exposed to higher levels of Hg and VB9.
Collapse
Affiliation(s)
- Fang Fang
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Lingyun Ding
- College of Health Science and Environmental Engineering, Shenzhen Technology University, Shenzhen 518118, China
| | - Yaoyu Zhang
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Xuejiao Qiao
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Lu Qian
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Ruqian Wei
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Hanchun Chen
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Haodong Ji
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Bin Pi
- Key Laboratory of Biological Targeting Diagnosis, Therapy and Rehabilitation of Guangdong Higher Education Institutes, Guangzhou Medical University, Guangzhou 510700, China
| | - Ming Hung Wong
- Soil Health Laboratory, Southern Federal University, Rostov-on-Don, Russia; Consortium on Health, Environment, Education and Research (CHEER), Department of Science and Environmental Studies, The Education University of Hong Kong, Tai Po, Hong Kong, China
| | - Huchun Tao
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Nan Xu
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Lijuan Zhang
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
| |
Collapse
|
2
|
Guo P, Du H, Zhao W, Xiong B, Wang M, He M, Flemetakis E, Hänsch R, Ma M, Rennenberg H, Wang D. Selenium- and chitosan-modified biochars reduce methylmercury contents in rice seeds with recruiting Bacillus to inhibit methylmercury production. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133236. [PMID: 38141298 DOI: 10.1016/j.jhazmat.2023.133236] [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: 09/28/2023] [Revised: 11/13/2023] [Accepted: 12/10/2023] [Indexed: 12/25/2023]
Abstract
Biochar could reshape microbial communities, thereby altering methylmercury (MeHg) concentrations in rice rhizosphere and seeds. However, it remains unclear whether and how biochar amendment perturbs microbe-mediated MeHg production in mercury (Hg) contaminated paddy soil. Here, we used pinecone-derived biochar and its six modified biochars to reveal the disturbance. Results showed that selenium- and chitosan-modified biochar significantly reduced MeHg concentrations in the rhizosphere by 85.83% and 63.90%, thereby decreasing MeHg contents in seeds by 86.37% and 75.50%. The two modified bicohars increased the abundance of putative Hg-resistant microorganisms Bacillus, the dominant microbe in rhizosphere. These reductions about MeHg could be facilitated by biochar sensitive microbes such as Oxalobacteraceae and Subgroup_7. Pinecone-derived biochar increased MeHg concentration in rhizosphere but unimpacted MeHg content in seeds was observed. This biochar decreased the abundance in Bacillus but enhanced in putative Hg methylator Desulfovibrio. The increasing MeHg concentration in rhizosphere could be improved by biochar sensitive microbes such as Saccharimonadales and Clostridia. Network analysis showed that Saccharimonadales and Clostridia were the most prominent keystone taxa in rhizosphere, and the three biochars manipulated abundances of the microbes related to MeHg production in rhizosphere by those biochar sensitive microbes. Therefore, selenium- and chitosan-modified biochar could reduce soil MeHg production by these microorganisms, and is helpful in controlling MeHg contamination in rice.
Collapse
Affiliation(s)
- Pan Guo
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University, Chongqing 400715, PR China
| | - Hongxia Du
- Chongqing Key Laboratory of Bio-resource for Bioenergy, College of Resources and Environment, Southwest University, Chongqing 400715, PR China
| | - Wancang Zhao
- Chongqing Key Laboratory of Karst Environment, School of Geographical Sciences, Southwest University, Chongqing 400715, PR China
| | - Bingcai Xiong
- Chongqing Key Laboratory of Bio-resource for Bioenergy, College of Resources and Environment, Southwest University, Chongqing 400715, PR China
| | - Mingxing Wang
- Chongqing Key Laboratory of Agricultural Resources and Environment, College of Resources and Environment, Chongqing 400715, PR China
| | - Mingyan He
- Chongqing Ecological Environment Monitoring Center, Chongqing 401147, PR China
| | - Emmanouil Flemetakis
- Laboratory of Molecular Biology, Department of Biotechnology, Agricultural University of Athens, 11855 Athens, Greece
| | - Robert Hänsch
- Institute for Plant Biology, Technische Universität Braunschweig, Humboldtstraße 1, D-38106, Braunschweig, Germany
| | - Ming Ma
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University, Chongqing 400715, PR China; Chongqing Key Laboratory of Bio-resource for Bioenergy, College of Resources and Environment, Southwest University, Chongqing 400715, PR China.
| | - Heinz Rennenberg
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University, Chongqing 400715, PR China
| | - Dingyong Wang
- Chongqing Key Laboratory of Agricultural Resources and Environment, College of Resources and Environment, Chongqing 400715, PR China
| |
Collapse
|
3
|
Zhou Y, Li S, Hintelmann H, Tang W, Zhong H. New insights into HgSe antagonism: Minor impact on inorganic Hg mobility while potential impacts on microorganisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 913:169705. [PMID: 38160847 DOI: 10.1016/j.scitotenv.2023.169705] [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: 10/27/2023] [Revised: 12/13/2023] [Accepted: 12/25/2023] [Indexed: 01/03/2024]
Abstract
Selenium (Se) is a crucial antagonistic factor of mercury (Hg) methylation in soil, with the transformation of inorganic Hg (IHg) to inert mercury selenide (HgSe) being the key mechanism. However, little evidence has been provided of the reduced Hg mobility at environmentally relevant doses of Hg and Se, and the potential impacts of Se on the activities of microbial methylators have been largely ignored. This knowledge gap hinders effective mitigation for methylmercury (MeHg) risks, considering that Hg supply and microbial methylators serve as materials and workers for MeHg production in soils. By monitoring the mobility of IHg and microbial activities after Se spike, we reported that 1) active methylation might be the premise of HgSe antagonism, as higher decreases in MeHg net production were found in soils with higher constants of Hg methylation rate; 2) IHg mobility did not significantly change upon Se addition in soils with high DOC concentrations, challenging the long-held view of Hg immobilization by Se; and 3) the activities of iron-reducing bacteria (FeRB), an important group of microbial methylators, might be potentially regulated by Se addition at a dose of 4 mg/kg. These findings provide empirical evidence that IHg mobility may not be the limiting factor under Se amendment and suggest the potential impacts of Se on microbial activities.
Collapse
Affiliation(s)
- Yang Zhou
- School of the Environment, Nanjing University, State Key Laboratory of Pollution Control and Resource Reuse, Nanjing, Jiangsu Province, China
| | - Shouying Li
- School of the Environment, Nanjing University, State Key Laboratory of Pollution Control and Resource Reuse, Nanjing, Jiangsu Province, China
| | - Holger Hintelmann
- Department of Chemistry, Trent University, Peterborough, ON, Canada; Water Quality Centre, Trent University, Peterborough, ON, Canada
| | - Wenli Tang
- School of the Environment, Nanjing University, State Key Laboratory of Pollution Control and Resource Reuse, Nanjing, Jiangsu Province, China.
| | - Huan Zhong
- School of the Environment, Nanjing University, State Key Laboratory of Pollution Control and Resource Reuse, Nanjing, Jiangsu Province, China.
| |
Collapse
|
4
|
Cai J, Yin B, Wang Y, Pan K, Xiao Y, Wang X. Gut microbiome play a crucial role in geographical and interspecies variations in mercury accumulation by fish. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169381. [PMID: 38101636 DOI: 10.1016/j.scitotenv.2023.169381] [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: 10/21/2023] [Revised: 11/24/2023] [Accepted: 12/12/2023] [Indexed: 12/17/2023]
Abstract
Mercury (Hg) contamination in fish has raised global concerns for decades. The Hg biotransformation can be manipulated by gut microbiome and it is found to have a substantial impact on the speciation and final fate of Hg in fish. However, the contribution of intestinal microbiota in geographical and interspecies variations in fish Hg levels has not been thoroughly understood. The present study compared the Hg levels in wild marine fish captured from two distinct regions in South China sea. We observed a quite "ironic" phenomenon that MeHg levels in carnivorous fish from a region with minimal human impacts (Xisha Islands, 92 ± 7.2 ng g-1 FW) were much higher than those from a region with severe human impacts (Daya Bay, 19 ± 0.41 ng g-1 FW). Furthermore, the results showed that gut microbiome determined Hg biotransformation and played a crucial role in the variances in fish Hg levels across different geographical locations and species. The intestinal methylators, rather than demethylators, were more significant in affecting Hg biotransformation in fish. The carnivorous species in Xisha Islands exhibited a higher abundance of intestinal methylators, leading to higher MeHg accumulation. Besides, the gut microbiome could be shaped in response to the elevated Hg levels in these fish, which may benefit their adaptation to Hg toxicity and overall health preservation. However, anthropogenic activities (particularly overfishing) in Daya Bay have severely affected the fish population, disrupting the reciprocal relationships between fish and intestinal microbiota and rendering them more susceptible to pathogenic microbes. Overall, this study provided a comprehensive understanding of the role of gut microbiome in Hg bioaccumulation in fish and offered valuable insights into the co-evolutionary dynamics between fish and gut microbiome in the presence of Hg exposure.
Collapse
Affiliation(s)
- Jieyi Cai
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Bingxin Yin
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Yunhui Wang
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Ke Pan
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Yayuan Xiao
- Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Science, Guangzhou 510300, China; Guangdong Provincial Key Laboratory of Fishery Ecology Environment, Guangzhou 510300, China
| | - Xun Wang
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China.
| |
Collapse
|
5
|
Solid-Water Interface Interaction of Selenium with Fe(II)-Bearing Minerals and Aqueous Fe(II) and S(-II) Ions in the Near-Field of the Radioactive Waste Disposal System. Int J Mol Sci 2022; 24:ijms24010315. [PMID: 36613759 PMCID: PMC9820544 DOI: 10.3390/ijms24010315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 12/09/2022] [Accepted: 12/20/2022] [Indexed: 12/28/2022] Open
Abstract
Selenium can be highly toxic in excess for both animals and humans. However, since its mobile forms can be easily adsorbed with ferric minerals, its mobility in the natural oxic environment is generally not an issue. Still, the removal and immobilization of the long-lived radioactive isotope 79Se from the contaminated anoxic waters is currently a significant concern. 79Se can be accessible in the case of radionuclides' leaching from radioactive waste disposals, where anoxic conditions prevail and where ferrous ions and Fe(II)-bearing minerals predominate after corrosion processes (e.g., magnetite). Therefore, reductive and adsorptive immobilizations by Fe(II)-bearing minerals are the primary mechanisms for removing redox-sensitive selenium. Even though the information on the sorptive interactions of selenium and Fe(II)-bearing minerals seems to be well documented, this review focuses specifically on the state of the available information on the effects of the redox properties of Fe(II)-bearing solid phases (e.g., ferrous oxides, hydroxides, sulfides, and carbonates) on selenium speciation via redox transformation and co-occurring coprecipitation.
Collapse
|
6
|
Xiong J, Wang H, Yao J, He Q, Ma J, Yang J, Liu C, Chen Y, Huangfu X, Liu H. A critical review on sulfur reduction of aqueous selenite: Mechanisms and applications. JOURNAL OF HAZARDOUS MATERIALS 2022; 422:126852. [PMID: 34399225 DOI: 10.1016/j.jhazmat.2021.126852] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 07/28/2021] [Accepted: 08/05/2021] [Indexed: 06/13/2023]
Abstract
Selenite, which is extremely toxic at high concentrations, can easily be enriched in natural aquatic environments due to human activities, which causes great harm to ecosystems. Sulfur reduction can effectively reduce soluble selenite in large quantities to nontoxic solid elemental selenium, which plays a significant role in controlling the toxicity and cycle of selenium. In view of the bright prospects of the sulfur reduction reaction of selenite, this review comprehensively summarizes the continuous development in the sulfidation of selenite. First, the geochemical characteristics of aqueous selenium in different sulfur systems involving species distribution and various phase types at Eh-pH conditions were summarized. Second, sulfur reductions of selenite with chemical sulfide in natural water environments, sulfur reductase and extracellular polymer substances containing thiol groups in sulfate-reducing bacteria have been reviewed to further understand the corresponding mechanisms, rates and influencing factors. Furthermore, applications of sulfur reduction of selenium, including removal of selenium, enrichment of selenium, synthesis of selenoproteins and prevention of leakage of selenium, were also summarized. Finally, this review identified future research needs for the sulfidation of selenite for environmental applications.
Collapse
Affiliation(s)
- Jiaming Xiong
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Hainan Wang
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Jinni Yao
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Qiang He
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China
| | - Jingjing Yang
- Center for Separation and Purification Materials & Technologies, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Caihong Liu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Yao Chen
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
| | - Xiaoliu Huangfu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China.
| | - Hongxia Liu
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing 400044, China.
| |
Collapse
|
7
|
Lv W, Zhan T, Abdelhafiz MA, Feng X, Meng B. Selenium-amended biochar mitigates inorganic mercury and methylmercury accumulation in rice (Oryza sativa L.). ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 291:118259. [PMID: 34600068 DOI: 10.1016/j.envpol.2021.118259] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 09/22/2021] [Accepted: 09/28/2021] [Indexed: 06/13/2023]
Abstract
Rice, as a dominant crop in China and Asia, can be a major route of methylmercury (MeHg) exposure for humans in inland China, especially in those living in mercury (Hg) polluted areas. Soil is the most prominent MeHg accumulation source for rice grains. The development of management practices to reduce MeHg in rice grains is crucial. This study explored the mitigation effect of biochar (BC) and sodium selenite-amended biochar (BC + Se) on MeHg production in paddy soil and accumulation in rice. Mercury-contaminated soil was treated with 1% and 5% of both BC and BC + Se. Soil MeHg concentration slightly increased under 1% BC/BC + Se compared to control soil but decreased at the rate of 5%. Moreover, soil phytoavailable MeHg (P-MeHg) diminished as the amount of Se-amended BC increased. BC + Se effectively mitigated MeHg accumulation in rice grains. The highest average contents of MeHg and inorganic Hg (IHg) in rice seeds were found in the control samples, followed by the 1%-BC, 5%-BC, 1%-BC + Se, and 5%-BC + Se samples. Under the 5%-BC + Se treatment, rice MeHg levels were reduced significantly (94%) compared to the control, and P-MeHg concentrations in soil were lower than all the other experimental groups throughout the rice-growing season. These results demonstrate the effectiveness of BC + Se in reducing MeHg and IHg accumulation in rice and could be employed for remediation of Hg polluted paddies.
Collapse
Affiliation(s)
- Wenqiang Lv
- School of Geography and Resources, Guizhou Education University, Guiyang, Guizhou, 550018, China
| | - Tianli Zhan
- Institute of Mountain Resources of Guizhou Province, Guiyang, 550001, China
| | - Mahmoud A Abdelhafiz
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China; 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, China; Center for Excellence in Quaternary Science and Global Change, Chinese Academy of Sciences, Xi'an, 710061, China
| | - Bo Meng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China.
| |
Collapse
|
8
|
Tran TAT, Dinh QT, Zhou F, Zhai H, Xue M, Du Z, Bañuelos GS, Liang D. Mechanisms underlying mercury detoxification in soil-plant systems after selenium application: a review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:46852-46876. [PMID: 34254235 DOI: 10.1007/s11356-021-15048-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 06/17/2021] [Indexed: 05/12/2023]
Abstract
Feasible countermeasures to mitigate mercury (Hg) accumulation and its deleterious effects on crops are urgently needed worldwide. Selenium (Se) fertilizer application is a cost-effective strategy to reduce Hg concentrations, promote agro-environmental sustainability and food safety, and decrease the public health risk posed by Hg-contaminated soils and its accumulation in food crops. This holistic review focuses on the processes and detoxification mechanisms of Hg in whole soil-plant systems after Se application. The reduction of Hg bioavailability in soil, the formation of inert HgSe or/and HgSe-containing proteinaceous complexes in the rhizosphere and/or roots, and the reduction of plant root uptake and translocation of Hg in plant after Se application are systemically discussed. In addition, the positive responses in plant physiological and biochemical processes to Se application under Hg stress are presented to show the possible mechanisms for protecting the plant. However, application of high levels Se showed synergistic toxic effect with Hg and inhibited plant growth. The effectiveness of Se application methods, rates, and species on Hg detoxification is compared. This review provides a good approach for plant production in Hg-contaminated areas to meet food security demands and reduce the public health risk.
Collapse
Affiliation(s)
- Thi Anh Thu Tran
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, Shaanxi, China
- Faculty of Natural Resources and Environmental Management, Thu Dau Mot University, Thu Dau Mot City, Binh Duong, Vietnam
| | - Quang Toan Dinh
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, Shaanxi, China
- Department of Natural Resources and Environment of Thanh Hoa, Thanh Hoa, 400570, Vietnam
| | - Fei Zhou
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Hui Zhai
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Mingyue Xue
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Zekun Du
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Gary S Bañuelos
- USDA, Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, Parlier, CA, 93648-9757, USA
| | - Dongli Liang
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, Shaanxi, China.
- Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, Shaanxi, China.
| |
Collapse
|
9
|
Zhou X, Yang J, Kronzucker HJ, Shi W. Selenium Biofortification and Interaction With Other Elements in Plants: A Review. FRONTIERS IN PLANT SCIENCE 2020; 11:586421. [PMID: 33224171 PMCID: PMC7674621 DOI: 10.3389/fpls.2020.586421] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 10/16/2020] [Indexed: 05/16/2023]
Abstract
Selenium (Se) is an essential element for humans and animals and its deficiency in the diet is a global problem. Crop plants are the main source of Se for consumers. Therefore, there is much interest in understanding the factors that govern the accumulation and distribution of Se in the tissues of crop plants and the mechanisms of interaction of Se absorption and accumulation with other elements, especially with a view toward optimizing Se biofortification. An ideal crop for human consumption is rich in essential nutrient elements such as Se, while showing reduced accumulation of toxic elements in its edible parts. This review focuses on (a) summarizing the nutritional functions of Se and the current understanding of Se uptake by plant roots, translocation of Se from roots to shoots, and accumulation of Se in grains; and (b) discussing the influence of nitrogen (N), phosphorus (P), and sulfur (S) on the biofortification of Se. In addition, we discuss interactions of Se with major toxicant metals (Hg, As, and Cd) frequently present in soil. We highlight key challenges in the quest to improve Se biofortification, with a focus on both agronomic practice and human health.
Collapse
Affiliation(s)
- Xinbin Zhou
- College of Resources and Environment, Southwest University, Chongqing, China
| | - Jing Yang
- College of Resources and Environment, Southwest University, Chongqing, China
| | - Herbert J. Kronzucker
- Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC, Canada
| | - Weiming Shi
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
| |
Collapse
|
10
|
Li Y, Hu W, Zhao J, Chen Q, Wang W, Li B, Li YF. Selenium decreases methylmercury and increases nutritional elements in rice growing in mercury-contaminated farmland. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 182:109447. [PMID: 31325809 DOI: 10.1016/j.ecoenv.2019.109447] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 07/04/2019] [Accepted: 07/13/2019] [Indexed: 05/09/2023]
Abstract
Methylmercury (MeHg) in rice grains grown in Hg-contaminated areas has raised environmental health concerns. Pot experiments found that selenium (Se) could reduce MeHg levels in rice grains. However, relatively high levels of Se (up to 6 mg/kg) were applied in these pot experiments, which may have adverse effects on the soil ecology due to the toxicity of Se. The aims of this work were thus to study 1) the effect of low levels of Se on the accumulation and distribution of Hg, especially MeHg, in rice plants grown in a real Hg-contaminated paddy field and 2) the effect of Se treatment on Se and other nutritional elements (e.g., Cu, Fe, Zn) in grains. A field study amended with different levels of Se was carried out in Hg-contaminated paddy soil in Qingzhen, Guizhou, China. The levels of MeHg and total Hg were studied using cold vapor atomic fluorescence spectrometry (CVAFS) and inductively coupled plasma mass spectrometry (ICP-MS). The distribution and relative quantification of elements in grains were examined by synchrotron radiation X-ray fluorescence analysis (SR-XRF). This field study showed that low levels of Se (0.5 μg/mL, corresponding to 0.15 mg Se/kg soils) could significantly reduce total Hg and MeHg in rice tissues. Se treatment also reduced Hg distribution in the embryo and endosperm and increased the levels of Fe, Cu, Zn and Se in grains and especially embryos. This field study implied that treatment with an appropriate level of Se is an effective approach to not only decrease the level of MeHg but to also increase the levels of nutritional elements such as Fe, Cu, Zn and Se in rice grains, which could bring beneficial effects for rice-dependent residents living in Hg-contaminated areas.
Collapse
Affiliation(s)
- Yunyun Li
- College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China; CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, And HKU-IHEP Joint Laboratory on Metallomics, And State Environmental Protection Engineering Center for Mercury Pollution Prevention and Control, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China
| | - Wenjun Hu
- College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Jiating Zhao
- CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, And HKU-IHEP Joint Laboratory on Metallomics, And State Environmental Protection Engineering Center for Mercury Pollution Prevention and Control, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China
| | - Qimin Chen
- College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Wei Wang
- College of Engineering, China Agricultural University, Beijing, 100083, China.
| | - Bai Li
- CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, And HKU-IHEP Joint Laboratory on Metallomics, And State Environmental Protection Engineering Center for Mercury Pollution Prevention and Control, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China
| | - Yu-Feng Li
- CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, And HKU-IHEP Joint Laboratory on Metallomics, And State Environmental Protection Engineering Center for Mercury Pollution Prevention and Control, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
| |
Collapse
|
11
|
Tan LC, Nancharaiah YV, Lu S, van Hullebusch ED, Gerlach R, Lens PNL. Biological treatment of selenium-laden wastewater containing nitrate and sulfate in an upflow anaerobic sludge bed reactor at pH 5.0. CHEMOSPHERE 2018; 211:684-693. [PMID: 30098564 DOI: 10.1016/j.chemosphere.2018.07.079] [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: 05/19/2017] [Revised: 05/03/2018] [Accepted: 07/15/2018] [Indexed: 06/08/2023]
Abstract
This study investigated the removal of selenate (SeO42-), sulfate (SO42-) and nitrate (NO3-) at different influent pH values ranging from 7.0 to 5.0 and 20 °C in an upflow anaerobic sludge blanket (UASB) reactor using lactate as an electron donor. At pH 5.0, the UASB reactor showed a 20-30% decrease in reactor performance compared to operation at pH 5.5 to 7.0, reaching removal efficiencies of 79%, 15%, 43% and 61% for NO3-, SO42-, Setotal and Sediss, respectively. However, the reactor stability was an issue upon lowering the pH to 5.0 and further experiments are recommended. The sludge formed during low pH operation had a fluffy, floc-like appearance with filamentous structure, possibly due to the low polysaccharide (PS) to protein (PN) ratio (0.01 PS/PN) in the soluble extracellular polymeric substances (EPS) matrix of the biomass. Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) analysis of the sludge confirmed Se oxyanion reduction and deposition of Se0 particles inside the biomass. Microbial community analysis using Illumina MiSeq sequencing revealed that the families of Campylobacteraceae and Desulfomicrobiaceae were the dominant phylotypes throughout the reactor operation at approximately 23% and 10% relative abundance, respectively. Furthermore, approximately 10% relative abundance of both Geobacteraceae and Spirochaetaceae was observed in the granular sludge during the pH 5.0 operation. Overall, this study demonstrated the feasibility of UASB operation at pH values ranging from 7.0 to 5.0 for removing Se and other oxyanions from wastewaters.
Collapse
Affiliation(s)
- Lea Chua Tan
- UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands.
| | - Yarlagadda V Nancharaiah
- Biofouling and Biofilm Process Section, Water and Steam Chemistry Division, Bhabha Atomic Research Centre, Kalpakkam 603102, Tamil Nadu, India
| | - Shipeng Lu
- Center for Biofilm Engineering, Montana State University, Bozeman, MT 59717, USA
| | - Eric D van Hullebusch
- UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands; Université Paris-Est, Laboratoire Géomatériaux et Environnement (EA 4508), UPEM, 77454 Marne-la-Vallée, France
| | - Robin Gerlach
- Center for Biofilm Engineering, Montana State University, Bozeman, MT 59717, USA
| | - Piet N L Lens
- UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands; Department of Chemistry and Bioengineering, Tampere University of Technology, P.O. Box 541, Tampere, Finland
| |
Collapse
|
12
|
Zhou L, Xu X, Xia S. Effects of sulfate on simultaneous nitrate and selenate removal in a hydrogen-based membrane biofilm reactor for groundwater treatment: Performance and biofilm microbial ecology. CHEMOSPHERE 2018; 211:254-260. [PMID: 30077104 DOI: 10.1016/j.chemosphere.2018.07.092] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 07/14/2018] [Accepted: 07/16/2018] [Indexed: 06/08/2023]
Abstract
Effects of sulfate on simultaneous nitrate and selenate removal in a hydrogen-based membrane biofilm reactor (MBfR) for groundwater treatment was identified with performance and biofilm microbial ecology. In whole operation, MBfR had almost 100% removal of nitration even with 50 mg mL-1 sulfate. Moreover, selenate degradation increased from 95% to approximate 100% with sulfate addition, indicating that sulfate had no obvious effects on nitrate degradation, and even partly promoted selenate removal. Short-term sulfate effect experiment further showed that Gibbs free energy of reduction (majority) and abiotic sulfide oxidation (especially between sulfate and selenate) contributed to degradable performance with sulfate. Microbial ecology showed that high percentage of Hydrogenophaga (≥75%) was one of the contributors for the stable and efficient nitrate degradation. Chemoheterotrophy (ratio>0.3) and dark hydrogen oxidation (ratio>0.3) were the majority of functional profile for biofilm in MBfR, and sulfate led to profiles of sulfate respiration and respiration of sulfur compounds in biofilm. Additionally, no special bacteria for selenate degradation was identified in biofilm microbial ecology, and selenate degradation was relied on Hydrogenophaga (75% of ecology percentage with sulfate addition) and Desulfovibrionaceae (4% of ecology percentage with sulfate addition). But with overloading sulfate, Desulfovibrionaceae was prior to sulfate degradation for energy supply and thus inhibited selenate removal.
Collapse
Affiliation(s)
- Lijie Zhou
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China
| | - Xiaoyin Xu
- State Key Laboratory of Pollution Control and Resource Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, PR China.
| | - Siqing Xia
- State Key Laboratory of Pollution Control and Resource Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, PR China.
| |
Collapse
|
13
|
Li X, Lan SM, Zhu ZP, Zhang C, Zeng GM, Liu YG, Cao WC, Song B, Yang H, Wang SF, Wu SH. The bioenergetics mechanisms and applications of sulfate-reducing bacteria in remediation of pollutants in drainage: A review. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2018; 158:162-170. [PMID: 29684746 DOI: 10.1016/j.ecoenv.2018.04.025] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 03/30/2018] [Accepted: 04/12/2018] [Indexed: 06/08/2023]
Abstract
Sulfate-reducing bacteria (SRB), a group of anaerobic prokaryotes, can use sulfur species as a terminal electron acceptor for the oxidation of organic compounds. They not only have significant ecological functions, but also play an important role in bioremediation of contaminated sites. Although numerous studies on metabolism and applications of SRB have been conducted, they still remain incompletely understood and even controversial. Fully understanding the metabolism of SRB paves the way for allowing the microorganisms to provide more beneficial services in bioremediation. Here we review progress in bioenergetics mechanisms and application of SRB including: (1) electron acceptors and donors for SRB; (2) pathway for sulfate reduction; (3) electron transfer in sulfate reduction; (4) application of SRB for economical and concomitant treatment of heavy metal, organic contaminants and sulfates. Moreover, current knowledge gaps and further research needs are identified.
Collapse
Affiliation(s)
- Xin Li
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
| | - Shi-Ming Lan
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Zhong-Ping Zhu
- School of Minerals processing and Bioengineering, Central South University, No. 932 South Lushan road, Changsha, Hunan 410083, PR China
| | - Chang Zhang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Guang-Ming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Yun-Guo Liu
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Wei-Cheng Cao
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Biao Song
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Hong Yang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Sheng-Fan Wang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| | - Shao-Hua Wu
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China
| |
Collapse
|
14
|
Bjerregaard P, St John T, Biuki NA, Biserova MP, Christensen A, Pedersen KL. Retention and distribution of methylmercury administered in the food in marine invertebrates: Effect of dietary selenium. MARINE ENVIRONMENTAL RESEARCH 2018; 138:76-83. [PMID: 29706366 DOI: 10.1016/j.marenvres.2018.04.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 04/13/2018] [Accepted: 04/16/2018] [Indexed: 06/08/2023]
Abstract
Methylmercury is transported along aquatic food chains from the lower trophic levels and selenium modulates the biokinetics of mercury in organisms in complex ways. We investigated the retention of orally administered methylmercury in various marine invertebrates and the effect of selenium hereon. Shrimps (Palaemon adpersus and P. elegans), blue mussels (Mytilus edulis), shore crabs (Carcinus maenas) and sea stars (Asterias rubens) eliminated methylmercury slowly (t½ = ½ to >1 year) and the copepod (Acartia tonsa) faster (t½ ∼ 12-24 h). Orally administered selenite augmented elimination of methylmercury in the copepod (in one of two experiments) and blue mussels, but not in shrimps, crabs and sea stars. Selenium generally alters the distribution of the body burden of mercury, leaving more mercury in muscle and less mercury in digestive glands or rest of the body - also in the species where total body retention is not affected.
Collapse
Affiliation(s)
- Poul Bjerregaard
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230, Odense M, Denmark.
| | - Tanja St John
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230, Odense M, Denmark
| | - Narges Amrollahi Biuki
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230, Odense M, Denmark; Department of Marine Biology, Faculty of Marine Sciences and Technology, University of Hormozgan, Iran
| | - Maya Petrova Biserova
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230, Odense M, Denmark
| | - Alan Christensen
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230, Odense M, Denmark
| | - Knud Ladegaard Pedersen
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230, Odense M, Denmark
| |
Collapse
|
15
|
Bao P, Li GX, Sun GX, Xu YY, Meharg AA, Zhu YG. The role of sulfate-reducing prokaryotes in the coupling of element biogeochemical cycling. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 613-614:398-408. [PMID: 28918271 DOI: 10.1016/j.scitotenv.2017.09.062] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 09/07/2017] [Accepted: 09/07/2017] [Indexed: 06/07/2023]
Abstract
Sulfate-reducing prokaryotes (SRP) represent a diverse group of heterotrophic and autotrophic microorganisms that are ubiquitous in anoxic habitats. In addition to their important role in both sulfur and carbon cycles, SRP are important biotic and abiotic regulators of a variety of sulfur-driven coupled biogeochemical cycling of elements, including: oxygen, nitrogen, chlorine, bromine, iodine and metal(loid)s. SRP gain energy form most of the coupling of element transformation. Once sulfate-reducing conditions are established, sulfide precipitation becomes the predominant abiotic mechanism of metal(loid)s transformation, followed by co-precipitation between metal(loid)s. Anthropogenic contamination, since the industrial revolution, has dramatically disturbed sulfur-driven biogeochemical cycling; making sulfur coupled elements transformation complicated and unpredictable. We hypothesise that sulfur might be detoxication agent for the organic and inorganic toxic compounds, through the metabolic activity of SRP. This review synthesizes the recent advances in the role of SRP in coupled biogeochemical cycling of diverse elements.
Collapse
Affiliation(s)
- Peng Bao
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, PR China; Ningbo Urban Environment Observation and Station, Chinese Academy of Sciences, Ningbo 315800, PR China
| | - Guo-Xiang Li
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, PR China; Ningbo Urban Environment Observation and Station, Chinese Academy of Sciences, Ningbo 315800, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Guo-Xin Sun
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100086, PR China
| | - Yao-Yang Xu
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, PR China; Ningbo Urban Environment Observation and Station, Chinese Academy of Sciences, Ningbo 315800, PR China
| | - Andrew A Meharg
- Institute of Global Food Security, Queen's University Belfast, David Keir Building, Stranmillis Road, Belfast BT9 5AG, United Kingdom
| | - Yong-Guan Zhu
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, PR China; State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100086, PR China.
| |
Collapse
|
16
|
Bigham GN, Murray KJ, Masue-Slowey Y, Henry EA. Biogeochemical controls on methylmercury in soils and sediments: Implications for site management. INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT 2017; 13:249-263. [PMID: 27427265 DOI: 10.1002/ieam.1822] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 05/10/2016] [Accepted: 06/28/2016] [Indexed: 05/25/2023]
Abstract
Management of Hg-contaminated sites poses particular challenges because methylmercury (MeHg), a potent bio-accumulative neurotoxin, is formed in the environment, and concentrations are not generally predictable based solely on total Hg (THg) concentrations. In this review, we examine the state of knowledge regarding the chemical, biological, and physical controls on MeHg production and identify those most critical for contaminated site assessment and management. We provide a list of parameters to assess Hg-contaminated soils and sediments with regard to their potential to be a source of MeHg to biota and therefore a risk to humans and ecological receptors. Because some measurable geochemical parameters (e.g., DOC) can have opposing effects on Hg methylation, we recommend focusing first on factors that describe the potential for Hg bio-accumulation: site characteristics, Hg and MeHg concentrations, Hg availability, and microbial activity, where practical. At some sites, more detailed assessment of biogeochemistry may be required to develop a conceptual site model for remedial decision making. Integr Environ Assess Manag 2017;13:249-263. © 2016 SETAC.
Collapse
|
17
|
Wang Y, Dang F, Zhong H, Wei Z, Li P. Effects of sulfate and selenite on mercury methylation in a mercury-contaminated rice paddy soil under anoxic conditions. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:4602-4608. [PMID: 26520099 DOI: 10.1007/s11356-015-5696-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 10/26/2015] [Indexed: 06/05/2023]
Abstract
Biogeochemical cycling of sulfur and selenium (Se) could play an important role in methylmercury (MeHg) dynamics in soil, while their potential effects on MeHg production in rice paddy soil are less understood. The main objective of this study was to explore the effects of sulfate and selenite on net MeHg production in contaminated rice paddy soil, characterized with massive MeHg production and thus MeHg accumulation in rice. A series of microcosm incubation experiments were conducted using a contaminated paddy soil amended with sulfate and/or selenite, in which sulfate-reducing bacteria were mainly responsible for MeHg production. Our results demonstrated that sulfate addition reduced solid and dissolved MeHg levels in soils by ≤18 and ≤25 %, respectively. Compared to sulfate, selenite was more effective in inhibiting net MeHg production, and the inhibitory effect depended largely on amended selenite doses. Moreover, sulfate input played a dual role in affecting Hg-Se interactions in soil, which could be explained by the dynamics of sulfate under anoxic conditions. Therefore, the effects of sulfate and selenium input should be carefully considered when assessing risk of Hg in anoxic environments (e.g., rice paddy field and wetland).
Collapse
Affiliation(s)
- Yongjie Wang
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, People's Republic of China
| | - Fei Dang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, People's Republic of China
| | - Huan Zhong
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, People's Republic of China.
- Environmental and Life Sciences Program (EnLS), Trent University, Peterborough, Ontario, Canada.
| | - Zhongbo Wei
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, People's Republic of China
| | - Ping Li
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, People's Republic of China
| |
Collapse
|
18
|
Wang Y, Dang F, Evans RD, Zhong H, Zhao J, Zhou D. Mechanistic understanding of MeHg-Se antagonism in soil-rice systems: the key role of antagonism in soil. Sci Rep 2016; 6:19477. [PMID: 26778218 PMCID: PMC4726087 DOI: 10.1038/srep19477] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 12/09/2015] [Indexed: 11/09/2022] Open
Abstract
Methylmercury (MeHg) accumulation in rice has great implications for human health. Here, effects of selenium (Se) on MeHg availability to rice are explored by growing rice under soil or foliar fertilization with Se. Results indicate that soil amendment with Se could reduce MeHg levels in soil and grain (maximally 73%). In contrast, foliar fertilization with Se enhanced plant Se levels (3–12 folds) without affecting grain MeHg concentrations. This evidence, along with the distinct distribution of MeHg and Se within the plant, demonstrate for the first time that Se-induced reduction in soil MeHg levels (i.e., MeHg-Se antagonism in soil) rather than MeHg-Se interactions within the plant might be the key process triggering the decreased grain MeHg levels under Se amendment. The reduction in soil MeHg concentrations could be mainly attributed to the formation of Hg-Se complexes (detected by TEM-EDX and XANES) and thus reduced microbial MeHg production. Moreover, selenite and selenate were equally effective in reducing soil MeHg concentrations, possibly because of rapid changes in Se speciation. The dominant role of Se-induced reduction in soil MeHg levels, which has been largely underestimated previously, together with the possible mechanisms advance our mechanistic understanding about MeHg dynamics in soil-rice systems.
Collapse
Affiliation(s)
- Yongjie Wang
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, P.R. China
| | - Fei Dang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, P.R. China
| | - R Douglas Evans
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, P.R. China.,Environmental and Resource Studies Program (ERS), Trent University, Peterborough, Ontario, Canada
| | - Huan Zhong
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, P.R. China.,Environmental and Life Sciences Program (EnLS), Trent University, Peterborough, Ontario, Canada
| | - Jiating Zhao
- Key Lab for Biomedical Effects of Nanomaterial and Nanosafety, Laboratory of Metallomics and Metalloproteomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Dongmei Zhou
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, P.R. China
| |
Collapse
|
19
|
Karita K, Sakamoto M, Yoshida M, Tatsuta N, Nakai K, Iwai-Shimada M, Iwata T, Maeda E, Yaginuma-Sakurai K, Satoh H, Murata K. [Recent Epidemiological Studies on Methylmercury, Mercury and Selenium]. Nihon Eiseigaku Zasshi 2016; 71:236-251. [PMID: 27725427 DOI: 10.1265/jjh.71.236] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
More than sixty years has passed since the outbreak of Minamata disease, and high-level methylmercury contaminations now seem nonexistent in Japan. However, mercury has been continuously discharged from natural sources and industrial activities, and the health effects on children susceptible to methylmercury exposure at low levels, in addition to mercury contamination from mercury or gold mining areas in developing countries, become a worldwide concern. In this article, we provide a recent overview of epidemiological studies regarding methylmercury and mercury. The following findings were obtained. (1) Many papers on exposure assessment of methylmercury/mercury have been published since the Minamata Convention on Mercury was adopted in 2013. (2) The most crucial problem is child developmental neurotoxicity resulting from prenatal exposure to methylmercury, but its precise assessment seems to be difficult because most of such effects are neither severe nor specific. (3) Several problems raised in birth cohort studies (e.g., whether IQ deficits due to prenatal methylmercury exposure remain when the children become adults, or whether the postnatal exposure at low levels also causes such adverse effects in children) remain unsolved. (4) Concurrent exposure models of methylmercury, lead, polychlorinated biphenyls, aresenic, and organochlorine pesticides, as well as possible antagonists such as polyunsaturated fatty acids and selenium, should be considered in the study design because the exposure levels of methylmercury are extremely low in developed countries. (5) Further animal experiments and molecular biological studies, in addition to human studies, are required to clarify the mechanism of methylmercury toxicity.
Collapse
Affiliation(s)
- Kanae Karita
- Department of Hygiene and Public Health, Kyorin University School of Medicine
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Vriens B, Lenz M, Charlet L, Berg M, Winkel LHE. Natural wetland emissions of methylated trace elements. Nat Commun 2015; 5:3035. [PMID: 24398909 DOI: 10.1038/ncomms4035] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 11/28/2013] [Indexed: 11/09/2022] Open
Abstract
Natural wetlands are well known for their significant methane emissions. However, trace element emissions via biomethylation and subsequent volatilization from pristine wetlands are virtually unstudied, even though wetlands constitute large reservoirs for trace elements. Here we show that the average volatile fluxes of selenium (<0.12 μg m(-2) day(-1)), sulphur (<37 μg m(-2) day(-1)) and arsenic (<0.54 μg m(-2) day(-1)) from a pristine peatland are considerable and consistent over two summers. We compare these fluxes with the total concentrations in the peat and show that selenium is up to 40 times more efficiently volatilized than arsenic, and over 100 times more efficiently volatilized than sulphur. We further show that the volatilization of selenium and arsenic increases with temperature, implying that emissions of these health-relevant trace elements will increase with global warming. We suggest that biomethylation and volatilization in wetlands play a crucial role in the mobilization and global biogeochemical cycling of trace elements.
Collapse
Affiliation(s)
- Bas Vriens
- 1] Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dubendorf CH-8600, Switzerland [2] Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Zurich CH-8092, Switzerland
| | - Markus Lenz
- 1] University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Institute for Ecopreneurship, Muttenz CH-4132, Switzerland [2] Department of Environmental Technology, Wageningen University, Wageningen 6708 WG, The Netherlands
| | - Laurent Charlet
- Earth Science Institute (ISTerre), University of Grenoble-I, Grenoble F-38041, France and Institut Universitaire de France, Paris 75005, France
| | - Michael Berg
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dubendorf CH-8600, Switzerland
| | - Lenny H E Winkel
- 1] Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dubendorf CH-8600, Switzerland [2] Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Zurich CH-8092, Switzerland
| |
Collapse
|
21
|
Goñi-Urriza M, Corsellis Y, Lanceleur L, Tessier E, Gury J, Monperrus M, Guyoneaud R. Relationships between bacterial energetic metabolism, mercury methylation potential, and hgcA/hgcB gene expression in Desulfovibrio dechloroacetivorans BerOc1. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:13764-71. [PMID: 25772867 DOI: 10.1007/s11356-015-4273-5] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 02/23/2015] [Indexed: 05/16/2023]
Abstract
The proteins encoded by the hgcA and hgcB genes are currently the only ones known to be involved in the mercury methylation by anaerobic microorganisms. However, no studies have been published to determine the relationships between their expression level and the net/gross methylmercury production. This study aimed to decipher the effect of growth conditions on methylmercury production and the relationships between hgcA and hgcB expression levels and net methylation. Desulfovibrio dechloroacetivorans strain BerOc1 was grown under sulfidogenic conditions with different carbon sources and electron donors as well as under fumarate respiration. A good correlation was found between the biomass production and the methylmercury production when the strain was grown under sulfate-reducing conditions. Methylmercury production was much higher under fumarate respiration when no sulfide was produced. During exponential growth, hgcA and hgcB gene expression levels were only slightly higher in the presence of inorganic mercury, and it was difficult to conclude whether there was a significant induction of hgcA and hgcB genes by inorganic mercury. Besides, no relationships between hgcA and hgcB expression levels and net mercury methylation could be observed when the strain was grown either under sulfate reduction or fumarate respiration, indicating that environmental factors had more influence than expression levels.
Collapse
Affiliation(s)
- Marisol Goñi-Urriza
- EEM-UMR IPREM CNRS 5254, Equipe Environnement et Microbiologie, University of Pau, Pau, France,
| | | | | | | | | | | | | |
Collapse
|
22
|
Truong HYT, Chen YW, Saleh M, Nehzati S, George GN, Pickering IJ, Belzile N. Proteomics of Desulfovibrio desulfuricans and X-ray absorption spectroscopy to investigate mercury methylation in the presence of selenium. Metallomics 2014; 6:465-75. [DOI: 10.1039/c3mt00323j] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|