1
|
Fang X, Colina Blanco AE, Christl I, Le Bars M, Straub D, Kleindienst S, Planer-Friedrich B, Zhao FJ, Kappler A, Kretzschmar R. Simultaneously decreasing arsenic and cadmium in rice by soil sulfate and limestone amendment under intermittent flooding. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 347:123786. [PMID: 38484962 DOI: 10.1016/j.envpol.2024.123786] [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: 12/16/2023] [Revised: 02/22/2024] [Accepted: 03/12/2024] [Indexed: 03/19/2024]
Abstract
Water management in paddy soils can effectively reduce the soil-to-rice grain transfer of either As or Cd, but not of both elements simultaneously due to the higher mobility of As under reducing and Cd under oxidizing soil conditions. Limestone amendment, the common form of liming, is well known for decreasing Cd accumulation in rice grown on acidic soils. Sulfate amendment was suggested to effectively decrease As accumulation in rice, especially under intermittent soil flooding. To study the unknown effects of combined sulfate and limestone amendment under intermittent flooding for simultaneously decreasing As and Cd in rice, we performed a pot experiment using an acidic sandy loam paddy soil. We also included a clay loam paddy soil to study the role of soil texture in low-As rice production under intermittent flooding. We found that liming not only decreased rice Cd concentrations but also greatly decreased dimethylarsenate (DMA) accumulation in rice. We hypothesize that this is due to suppressed sulfate reduction, As methylation, and As thiolation by liming in the sulfate-amended soil and a higher share of deprotonated DMA at higher pH which is taken up less readily than protonated DMA. Decreased gene abundance of potential soil sulfate-reducers by liming further supported our hypothesis. Combined sulfate and limestone amendment to the acidic sandy loam soil produced rice with 43% lower inorganic As, 72% lower DMA, and 68% lower Cd compared to the control soil without amendment. A tradeoff between soil aeration and water availability was observed for the clay loam soil, suggesting difficulties to decrease As in rice while avoiding plant water stress under intermittent flooding in fine-textured soils. Our results suggest that combining sulfate amendment, liming, and intermittent flooding can help to secure rice safety when the presence of both As and Cd in coarse-textured soils is of concern.
Collapse
Affiliation(s)
- Xu Fang
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, CHN, ETH Zurich, CH-8092, Zurich, Switzerland.
| | - Andrea E Colina Blanco
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440, Bayreuth, Germany
| | - Iso Christl
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, CHN, ETH Zurich, CH-8092, Zurich, Switzerland
| | - Maureen Le Bars
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, CHN, ETH Zurich, CH-8092, Zurich, Switzerland
| | - Daniel Straub
- Quantitative Biology Center (QBiC), University of Tuebingen, 72076, Tuebingen, Germany; Cluster of Excellence: EXC 2124: Controlling Microbes to Fight Infection, Tuebingen, 72076, Germany
| | - Sara Kleindienst
- Microbial Ecology, Department of Geosciences, University of Tuebingen, 72076, Tuebingen, Germany; Now: Department of Environmental Microbiology, Institute for Sanitary Engineering, Water Quality and Solid Waste Management (ISWA), University of Stuttgart, Stuttgart, 70569, Germany
| | - Britta Planer-Friedrich
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440, Bayreuth, Germany
| | - Fang-Jie Zhao
- College of Resources and Environmental Sciences, Nanjing Agricultural University, 210095, Nanjing, China
| | - Andreas Kappler
- Cluster of Excellence: EXC 2124: Controlling Microbes to Fight Infection, Tuebingen, 72076, Germany; Geomicrobiology, Department of Geosciences, Tuebingen University, 72076, Tuebingen, Germany
| | - Ruben Kretzschmar
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, CHN, ETH Zurich, CH-8092, Zurich, Switzerland
| |
Collapse
|
2
|
Colina Blanco AE, Pischke E, Higa Mori A, Kerl CF, Clemens S, Planer-Friedrich B. In Planta Arsenic Thiolation in Rice and Arabidopsis thaliana. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:21846-21854. [PMID: 38093687 DOI: 10.1021/acs.est.3c06603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
Inorganic and methylated thioarsenates have recently been reported to form in paddy soil pore waters and accumulate in rice grains. Among them, dimethylmonothioarsenate (DMMTA) is particularly relevant because of its high cytotoxicity and potential misidentification as nonregulated dimethylarsenate (DMA). Studying DMMTA uptake and flag leaf, grain, and husk accumulation in rice plants during grain filling, substantial dethiolation to DMA was observed with only 8.0 ± 0.1, 9.1 ± 0.6, and 1.4 ± 0.2% DMMTA remaining, respectively. More surprisingly, similar shares of DMMTA were observed in control experiments with DMA, indicating in planta DMA thiolation. Exposure of different rice seedling varieties to not only DMA but also to arsenite and monomethylarsenate (MMA) revealed in planta thiolation as a common process in rice. Up to 35 ± 7% DMA thiolation was further observed in the shoots and roots of the model plant Arabidopsis thaliana. Parameters determining the ratio and kinetics of thiolation versus dethiolation are unknown, yet, but less DMA thiolation in glutathione-deficient mutants compared to wild-type plants suggested glutathione concentration as one potential parameter. Our results demonstrate that pore water is not the only source for thioarsenates in rice grains and that especially the currently nonregulated DMA needs to be monitored as a potential precursor of DMMTA formation inside rice plants.
Collapse
Affiliation(s)
- Andrea E Colina Blanco
- Environmental Geochemistry Group, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany
| | - Erik Pischke
- Plant Physiology, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, D-95440 Bayreuth, Germany
| | - Alejandra Higa Mori
- Environmental Geochemistry Group, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany
| | - Carolin F Kerl
- Environmental Geochemistry Group, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany
| | - Stephan Clemens
- Plant Physiology, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, D-95440 Bayreuth, Germany
| | - Britta Planer-Friedrich
- Environmental Geochemistry Group, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany
| |
Collapse
|
3
|
Noh CH, Chun SH, Lim J, Kim MH, Choi S, Joo YS, Lee KW. Monitoring arsenic species concentration in rice-based processed products distributed in South Korean markets and related risk assessment. Food Sci Biotechnol 2023; 32:1361-1372. [PMID: 37457401 PMCID: PMC10348953 DOI: 10.1007/s10068-023-01270-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 01/10/2023] [Accepted: 01/27/2023] [Indexed: 03/09/2023] Open
Abstract
Rice is an important grain as a major source of carbohydrates in Asia but contains more arsenic (As) than other grains. A total of 239 rice-based processed foods (rice, n = 30; rice cake, n = 30; porridge, n = 39; noodles, n = 33; bread, n = 20; snack, n = 59; powder, n = 28) were purchased in 2019 from domestic markets to measure total As (tAs) and As species. The average tAs and inorganic As (iAs) in each sample group ranged from 20 to 180 μg/kg (porridge for baby to noodle) and 4.4-85 μg/kg (porridge for baby to powder), respectively. The correlation between the iAs and tAs was affected by the variety of ingredients, such as the presence of seaweed (tAs) and the milling type of rice (iAs). Although rice cakes and baby rice-based powders are a source of concern for both adults and children, respectively, risk assessments indicate that most rice-based foods are generally safe to consume in South Korea. Graphical abstract Supplementary Information The online version contains supplementary material available at 10.1007/s10068-023-01270-9.
Collapse
Affiliation(s)
- Chang-Hyun Noh
- Department of Biotechnology, College of Life Science & Biotechnology, Korea University, 145, Anam-Ro, Seongbuk-Gu, Seoul, 02841 Republic of Korea
| | - Su-Hyun Chun
- Institute of Biomedical Science and Food Safety, Korea University, 145, Anam-Ro, Seongbuk-Gu, Seoul, 02841 Republic of Korea
- Pro_B Co., Ltd, 145, Anam-Ro, Seongbuk-Gu, Seoul, 02841 Republic of Korea
| | - JoonKi Lim
- Department of Statistics, College of Natural Science, Dongguk University, 30, Pildong-Ro 1-Gil, Jung-Gu, Seoul, 04620 Republic of Korea
| | - Min-hyuk Kim
- Department of Biotechnology, College of Life Science & Biotechnology, Korea University, 145, Anam-Ro, Seongbuk-Gu, Seoul, 02841 Republic of Korea
| | - Seogyeong Choi
- Department of Biotechnology, College of Life Science & Biotechnology, Korea University, 145, Anam-Ro, Seongbuk-Gu, Seoul, 02841 Republic of Korea
| | - Yong-Sung Joo
- Department of Statistics, College of Natural Science, Dongguk University, 30, Pildong-Ro 1-Gil, Jung-Gu, Seoul, 04620 Republic of Korea
| | - Kwang-Won Lee
- Department of Biotechnology, College of Life Science & Biotechnology, Korea University, 145, Anam-Ro, Seongbuk-Gu, Seoul, 02841 Republic of Korea
- Department of Food Bioscience and Technology, College of Life Sciences and Biotechnology, Korea University, 145, Anam-Ro, Seongbuk-Gu, Seoul, 02841 Republic of Korea
| |
Collapse
|
4
|
Wang L, Guo Q, Wu G, Yu Z, Ninin JML, Planer-Friedrich B. Methanogens-Driven Arsenic Methylation Preceding Formation of Methylated Thioarsenates in Sulfide-Rich Hot Springs. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:7410-7420. [PMID: 37134202 DOI: 10.1021/acs.est.2c08814] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Hot springs represent a major source of arsenic release into the environment. Speciation is typically reported to be dominated by arsenite, arsenate, and inorganic thiolated arsenates. Much less is known about the relevance and formation of methylated thioarsenates, a group with species of high mobility and toxicity. In hot spring samples taken from the Tengchong volcanic region in China, methylated thioarsenates contributed up to 13% to total arsenic. Enrichment cultures were obtained from the corresponding sediment samples and incubated to assess their capability to convert arsenite into methylated thioarsenates over time and in the presence of different microbial inhibitors. In contrast to observations in other environmental systems (e.g., paddy soils), there was no solid evidence, supporting that the sulfate-reducing bacteria contributed to the arsenic methylation. Methanosarcina, the sole genus of methanogens detected in the enrichment cultures, as well as Methanosarcina thermophila TM-1, a pure strain within the genus, did methylate arsenic. We propose that methylated thioarsenates in a typical sulfide-rich hot spring environment like Tengchong form via a combination of biotic arsenic methylation driven by thermophilic methanogens and arsenic thiolation with either geogenic sulfide or sulfide produced by sulfate-reducing bacteria.
Collapse
Affiliation(s)
- Luxia Wang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, Hubei, P. R. China
- School of Environmental Studies, China University of Geosciences, 430074 Wuhan, Hubei, P. R. China
| | - Qinghai Guo
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, Hubei, P. R. China
- School of Environmental Studies, China University of Geosciences, 430074 Wuhan, Hubei, P. R. China
| | - Geng Wu
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, Hubei, P. R. China
| | - Zhicheng Yu
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, Hubei, P. R. China
| | - José Miguel Léon Ninin
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| | - Britta Planer-Friedrich
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany
| |
Collapse
|
5
|
Jeong S, Kang J, Cho M, An J, Yoon HO. New insights into surface behavior of dimethylated arsenicals on montmorillonite using X-ray absorption spectroscopy. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 852:158531. [PMID: 36063923 DOI: 10.1016/j.scitotenv.2022.158531] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 08/21/2022] [Accepted: 08/31/2022] [Indexed: 06/15/2023]
Abstract
Although recent studies have revealed the occurrence of dimethylated arsenicals, little is known about their behavior in environment. This study investigates the adsorption behavior of dimethylarsinic acid (DMAV), dimethyldithioarsinic acid (DMDTAV), and dimethylmonothioarsinic acid (DMMTAV) on montmorillonite. Complicated transformations among arsenicals under normal environmental conditions were also considered. Our results clearly demonstrate that DMDTAV was oxidized to DMMTAV, which was relatively stable but partially transformed to DMAV when exposed to air during adsorption. The transformed DMAV exhibited high adsorption affinities for montmorillonite, while DMMTAV and DMDTAV were not appreciably retained by montmorillonite for 48 h. This is the first study to provide insights into DMDTAV oxidation under environmental conditions. X-ray absorption near edge structure and extended X-ray absorption fine structure studies confirmed that most of the adsorbed arsenicals on montmorillonite were DMAV. The significantly different bonding characteristics of each adsorbed DMAV provide direct evidence for the transformation of DMAV from DMDTAV and DMMTAV. Our study suggests the importance of incorporating the DMMTAV in the realistic risk management for soil environments because it is highly toxic, easily transformed from DMDTAV, and stable in the environment.
Collapse
Affiliation(s)
- Seulki Jeong
- Seoul Center, Korea Basic Science Institute, 6-7, Inchon-ro 22-gil, Seongbuk-gu, Seoul 02855, Republic of Korea
| | - Jinback Kang
- Seoul Center, Korea Basic Science Institute, 6-7, Inchon-ro 22-gil, Seongbuk-gu, Seoul 02855, Republic of Korea
| | - Minkyu Cho
- Seoul Center, Korea Basic Science Institute, 6-7, Inchon-ro 22-gil, Seongbuk-gu, Seoul 02855, Republic of Korea
| | - Jinsung An
- Department of Civil & Environmental Engineering, Hanyang University, Ansan 15588, Republic of Korea
| | - Hye-On Yoon
- Seoul Center, Korea Basic Science Institute, 6-7, Inchon-ro 22-gil, Seongbuk-gu, Seoul 02855, Republic of Korea.
| |
Collapse
|
6
|
Yoon SG, Kwak IS, Yoon HO, An J. Adsorption Characteristics of Dimethylated Arsenicals on Iron Oxide-Modified Rice Husk Biochar. TOXICS 2022; 10:703. [PMID: 36422911 PMCID: PMC9692524 DOI: 10.3390/toxics10110703] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/11/2022] [Accepted: 11/12/2022] [Indexed: 06/16/2023]
Abstract
In this study, the adsorption characteristics of dimethylated arsenicals to rice husk biochar (BC) and Fe/biochar composite (FeBC) were assessed through isothermal adsorption experiments and X-ray absorption spectroscopy analysis. The maximal adsorption capacities (qm) of inorganic arsenate, calculated using the Langmuir isotherm equation, were 1.28 and 6.32 mg/g for BC and FeBC, respectively. Moreover, dimethylated arsenicals did not adsorb to BC at all, and in the case of FeBC, qm values of dimethylarsinic acid (DMA(V)), dimethylmonothioarsinic acid (DMMTA(V)), and dimethyldithioarsinic acid (DMDTA(V)) were calculated to be 7.08, 0.43, and 0.28 mg/g, respectively. This was due to the formation of iron oxide (i.e., two-line ferrihydrite) on the surface of BC. Linear combination fitting using As K-edge X-ray absorption near edge structure spectra confirmed that all chemical forms of dimethylated arsenicals adsorbed on the two-line ferrihydrite were DMA(V). Thus, FeBC could retain highly mobile and toxic arsenicals such as DMMTA(V) and DMDTA(V)) in the environment, and transform them into DMA(V) with relatively low toxicity.
Collapse
Affiliation(s)
- Sang-Gyu Yoon
- Department of Environment Safety System Engineering, Semyung University, Jecheon 27136, Republic of Korea
| | - Ihn-Sil Kwak
- Department of Ocean Integrated Science, Chonnam National University, Yeosu 59626, Republic of Korea
| | - Hye-On Yoon
- Korea Basic Science Institute, 145 Anam-ro, Seoul 02841, Republic of Korea
| | - Jinsung An
- Department of Civil & Environmental Engineering, Hanyang University, Ansan 15588, Republic of Korea
| |
Collapse
|
7
|
Chen C, Yang B, Gao A, Yu Y, Zhao FJ. Transformation of arsenic species by diverse endophytic bacteria of rice roots. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 309:119825. [PMID: 35870529 DOI: 10.1016/j.envpol.2022.119825] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 07/17/2022] [Accepted: 07/18/2022] [Indexed: 06/15/2023]
Abstract
Rice growing in flooded paddy soil often accumulates considerable levels of inorganic and organic arsenic (As) species, which may cause toxicity to plants and/or pose a risk to human health. The bioavailability and toxicity of As in soil depends on its chemical species, which undergo multiple transformations driven primarily by soil microbes. However, the role of endophytes inside rice roots in As species transformation remains largely unknown. We quantified the abundances of microbial functional genes involved in As transformation in the endosphere and rhizosphere of rice roots growing in three paddy soils in a pot experiment. We also isolated 46 different bacterial endophytes and tested their abilities to transform various As species. The absolute abundances of the arsenate reductase gene arsC and the dissimilatory arsenate reductase gene arrA in the endosphere were comparable to those in the rhizosphere, whereas the absolute abundances of the arsenite methylation gene arsM and arsenite oxidation gene aioA in the endosphere were lower. After normalization based on the bacterial 16S rRNA gene, all four As transformation genes showed higher relative abundances in the endosphere than in the rhizosphere. Consistent with the functional gene data, all of the 30 aerobic endophytic isolates were able to reduce arsenate, but only 3 strains could oxidize arsenite. Among the 16 anaerobic endophytic isolates, 4 strains belonging to Desulfovibrio, Terrisporobacter or Clostridium could methylate arsenite and/or methylarsenite. Six strains of aerobic endophytes could demethylate methylarsenite, among which three strains also could reduce and demethylate methylarsenate. None of the isolates could demethylate dimethylarsenate. These results suggest that diverse endophytes living inside rice roots could participate in As species transformation and affect As accumulation and species distribution in rice plants.
Collapse
Affiliation(s)
- Chuan Chen
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Provincial Key Laboratory for Organic Solid Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Baoyun Yang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Provincial Key Laboratory for Organic Solid Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Axiang Gao
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Provincial Key Laboratory for Organic Solid Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yu Yu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Provincial Key Laboratory for Organic Solid Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Fang-Jie Zhao
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Jiangsu Provincial Key Laboratory for Organic Solid Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China.
| |
Collapse
|
8
|
Müller V, Chavez-Capilla T, Feldmann J, Mestrot A. Increasing temperature and flooding enhance arsenic release and biotransformations in Swiss soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:156049. [PMID: 35598661 DOI: 10.1016/j.scitotenv.2022.156049] [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: 02/28/2022] [Revised: 04/25/2022] [Accepted: 05/14/2022] [Indexed: 06/15/2023]
Abstract
Reductive dissolution is one of the main causes for arsenic (As) mobilisation in flooded soils while biomethylation and biovolatilisation are two microbial mechanisms that greatly influence the mobility and toxicity of As. Climate change results in more extreme weather events such as flooding and higher temperatures, potentially leading to an increase in As release and biotransformations. Here, we investigated the effects of flooding and temperature on As release, biomethylation and biovolatilisation from As-rich soils with different pH and source of As (one acidic and anthropogenic (Salanfe) and one neutral and geogenic (Liesberg)). Flooded soils incubated at 23 °C for two weeks showed a ~ 3-fold (Liesberg site) and ~ 7-fold (Salanfe site) increase in the total As concentration of soil solution compared to those incubated at 18 °C. Methyl- and thio-As species were found in the acidic soil and soil solution. High temperatures enhanced thiolation and methylation although inorganic As was predominant. We also show that volatile As fluxes increased more than 4-fold between treatments, from 18 ± 5 ng/kg/d at 18 °C to 75 ± 6 ng/kg/d at 23 °C from Salanfe soil. Our results suggest that high As soils with acidic pH can become an important source of As to the surrounding environment according to realistic climatic scenarios, and that biovolatilisation is very sensitive to increases in temperature. This study provides new data and further justifies further investigations into climate-induced changes on As release and speciation and its links to important factors such as microbial ecology and sulfate or iron biogeochemistry. SYNOPSIS: In the studied Swiss soils, elevated temperature increases arsenic mobility through volatilisation and methylation.
Collapse
Affiliation(s)
- Viktoria Müller
- TESLA - Environmental Analytical Chemistry, Institute of Chemistry, University of Graz, 8010 Graz, Austria
| | - Teresa Chavez-Capilla
- Institute of Geography, University of Bern, Hallerstrasse 12, 3012 Bern, Switzerland
| | - Jörg Feldmann
- TESLA - Environmental Analytical Chemistry, Institute of Chemistry, University of Graz, 8010 Graz, Austria
| | - Adrien Mestrot
- Institute of Geography, University of Bern, Hallerstrasse 12, 3012 Bern, Switzerland.
| |
Collapse
|
9
|
Yan K, Planer-Friedrich B, Knobloch PVT, Guo Q, Wang L, Zhao Q. Effects of thiolation and methylation on arsenic sorption to geothermal sediments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 827:154016. [PMID: 35271921 DOI: 10.1016/j.scitotenv.2022.154016] [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: 12/15/2021] [Revised: 02/14/2022] [Accepted: 02/15/2022] [Indexed: 06/14/2023]
Abstract
Arsenic (As) from deep crust is transported by geothermal waters to the earth surface and retained by sediment through adsorption, which depends significantly on the occurring As species. Adsorption of oxyarsenic species (i.e. arsenite [iAs(III)] and arsenate [iAs(V)]) on pure minerals was intensively investigated, yet studies with natural sediments and less known As species are scarce. To fill this gap, we investigated adsorption kinetics of nine different As species onto three typical geothermal sediments with different sedimentary organic matter (SOM) and iron (Fe) levels under anaerobic, sulfidic conditions (pH = 6). A multispecies pseudo-second-order (MPSO) model was applied to extract the adsorption rates of individual As species. Results showed that only the sediment with both high SOM and high Fe exhibited considerable As adsorption capacity. Air exposure or rise of either SOM or Fe levels in sediment favoured de-thiolation of aqueous thioarsenates, except for dimethylated thioarsenates. The overall adsorbed amount of the spiked As was affected by concurrent (de-)thiolation of the initial species, and the rates of their adsorption to the high SOM and high Fe sediment decreased in the order of tetrathioarsenate (TetraTA) > monothioarsenate (MTA) > iAs(V) > monomethyl arsenate (MMA) > dimethyl arsenate (DMA) > iAs(III) > monomethyl monothioarsenate (MMMTA) > dimethyl monothioarsenate (DMMTA) > dimethyl dithioarsenate (DMDTA). The fastest and slowest adsorption were suggested for inorganic thioarsenates and methylated thioarsenates, respectively. Therefore, under typical geothermal scenarios, thiolation of inorganic As would not necessarily increase its mobility, but the formation of methylated oxyarsenates and their further thiolation would endow geothermal As with strong migration ability.
Collapse
Affiliation(s)
- Ketao Yan
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, Hubei, PR China; School of Environmental Studies, China University of Geosciences, 430074 Wuhan, Hubei, PR China
| | - Britta Planer-Friedrich
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, Universitätsstraße 30, Bayreuth 95447, Germany
| | - Philipp Victor Thorben Knobloch
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, Universitätsstraße 30, Bayreuth 95447, Germany
| | - Qinghai Guo
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, Hubei, PR China; School of Environmental Studies, China University of Geosciences, 430074 Wuhan, Hubei, PR China.
| | - Luxia Wang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, Hubei, PR China; School of Environmental Studies, China University of Geosciences, 430074 Wuhan, Hubei, PR China
| | - Qian Zhao
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074 Wuhan, Hubei, PR China; School of Environmental Studies, China University of Geosciences, 430074 Wuhan, Hubei, PR China
| |
Collapse
|
10
|
Yoon SG, Kim YE, Chae C, An J, Yoon HO. Dimethylmonothioarsinic acid and dimethyldithioarsinic acid in the environment: Sorption characteristics on 2-line ferrihydrite and acute toxicity to Daphnia magna. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2022; 44:925-932. [PMID: 34120301 DOI: 10.1007/s10653-021-01005-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 06/05/2021] [Indexed: 06/12/2023]
Abstract
Dimethylmonothioarsinic acid (DMMTA(V)) and dimethyldithioarsinic acid (DMDTA(V)), which are commonly found in landfill leachate and pore water of rice paddy soil, have attracted considerable attention for their high toxicity. This study aims to evaluate the behavior and potential risks of DMMTA(V) and DMDTA(V) in the environment by conducting an equilibrium sorption test using 2-line ferrihydrite and acute toxicity (immobilization) test using Daphnia magna. The overall maximum sorption capacity (qm) derived by the Langmuir isotherm model showed an increase in the order of inorganic arsenate (As(V)) > dimethylarsinic acid (DMA(V)) > DMMTA(V) > DMDTA(V), which was likely due to steric hindrance due to the presence of methyl and thiol groups. Moreover, DMMTA(V) and DMDTA(V) showed no or negligible change in qm with pH change, while qm decreased rapidly with increasing pH in As(V) and DMA(V). The 50% inhibition concentrations (IC50) for As(V), DMA(V), DMMTA(V), and DMDTA(V), which were measured after 48 h exposure to D. magna, were 9.5, > 30, 1.7, and 6.5 mg/L, respectively. Overall, the results demonstrated that DMMTA(V) and DMDTA(V) have high mobility and eco-toxicity in the environment and that methylated thioarsenicals should be accurately monitored and controlled.
Collapse
Affiliation(s)
- Sang-Gyu Yoon
- Department of Environment Safety System Engineering, Semyung University, 65 Semyung-ro, Jecheon-si, Chungcheongbuk-do, 27136, Republic of Korea
| | - Ye-Eun Kim
- Department of Biological and Environmental Engineering, Semyung University, 65 Semyung-ro, Jecheon-si, Chungcheongbuk-do, 27136, Republic of Korea
| | - Changwon Chae
- Department of Biological and Environmental Engineering, Semyung University, 65 Semyung-ro, Jecheon-si, Chungcheongbuk-do, 27136, Republic of Korea
| | - Jinsung An
- Department of Environment Safety System Engineering, Semyung University, 65 Semyung-ro, Jecheon-si, Chungcheongbuk-do, 27136, Republic of Korea.
- Department of Biological and Environmental Engineering, Semyung University, 65 Semyung-ro, Jecheon-si, Chungcheongbuk-do, 27136, Republic of Korea.
| | - Hye-On Yoon
- Korea Basic Science Institute, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea.
| |
Collapse
|
11
|
Dai J, Chen C, Gao AX, Tang Z, Kopittke PM, Zhao FJ, Wang P. Dynamics of Dimethylated Monothioarsenate (DMMTA) in Paddy Soils and Its Accumulation in Rice Grains. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:8665-8674. [PMID: 34110124 DOI: 10.1021/acs.est.1c00133] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Arsenic species transformation in paddy soils has important implications for arsenic accumulation in rice grains and its safety to the consumers. Methylated thioarsenates including highly toxic dimethylated monothioarsenate (DMMTA) have been detected in paddy soils, but their production and dynamics remain poorly understood. In the present study, we first optimized a HPLC-ICP-MS method to quantify methylated thioarsenate species. Using this method together with 10 mM diethylenetriamine pentaacetate (DTPA) to preserve As speciation, we investigated methylated thioarsenate species in porewaters of seven As-contaminated soils incubated under flooded conditions and of two paddy fields. DMMTA was the main methylated thioarsenate species in the porewaters in both incubated soils and paddy fields, with concentrations ranging from 0.2 to 36.2 μg/L and representing ca. 58% of its precursor dimethylarsenate (DMA). The temporal production and dynamics of DMMTA were linked with the DMA concentrations. When soils were drained, DMMTA was converted to DMA. In the two paddy fields, DMMTA concentrations in rice grains were 0.4-10.1 μg/kg. Addition of sulfur fertilizer and rice straw incorporation increased grain DMMTA by 9-28%. These results suggest that DMMTA is an important As species in paddy soils and can accumulate in rice grains, presenting a risk to food safety and human health.
Collapse
Affiliation(s)
- Jun Dai
- Jiangsu Key Laboratory for Organic Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Chuan Chen
- Jiangsu Key Laboratory for Organic Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - A-Xiang Gao
- Jiangsu Key Laboratory for Organic Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhu Tang
- Jiangsu Key Laboratory for Organic Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Peter M Kopittke
- School of Agriculture and Food Sciences, The University of Queensland, St Lucia 4072, Australia
| | - Fang-Jie Zhao
- Jiangsu Key Laboratory for Organic Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Peng Wang
- Jiangsu Key Laboratory for Organic Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| |
Collapse
|
12
|
Yang Y, Chi L, Lai Y, Hsiao YC, Ru H, Lu K. The gut microbiome and arsenic-induced disease-iAs metabolism in mice. Curr Environ Health Rep 2021; 8:89-97. [PMID: 33852125 PMCID: PMC8728881 DOI: 10.1007/s40572-021-00305-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/29/2021] [Indexed: 12/26/2022]
Abstract
PURPOSE OF REVIEW This review summarizes inorganic arsenic (iAs) metabolism and toxicity in mice and the gut microbiome and how iAs and the gut microbiome interact to induce diseases. RECENT FINDINGS Recently, a variety of studies have started to reveal the interactions between iAs and the gut microbiome. Evidence shows that gut bacteria can influence iAs biotransformation and disease risks. The gut microbiome can directly metabolize iAs, and it can also indirectly be involved in iAs metabolism through the host, such as altering iAs absorption, cofactors, and genes related to iAs metabolism. Many factors, such as iAs metabolism influenced by the gut microbiome, and microbiome metabolites perturbed by iAs can lead to different disease risks. iAs is a widespread toxic metalloid in environment, and iAs toxicity has become a global health issue. iAs is subject to metabolic reactions after entering the host body, including methylation, demethylation, oxidation, reduction, and thiolation. Different arsenic species, including trivalent and pentavalent forms and inorganic and organic forms, determine their toxicity. iAs poisoning is predominately caused by contaminated drinking water and food, and chronic arsenic toxicity can cause various diseases. Therefore, studies of iAs metabolism are important for understanding iAs associated disease risks.
Collapse
Affiliation(s)
- Yifei Yang
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Liang Chi
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Yunjia Lai
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Yun-Chung Hsiao
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Hongyu Ru
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Kun Lu
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
| |
Collapse
|
13
|
Sharma SS, Kumar V, Dietz KJ. Emerging Trends in Metalloid-Dependent Signaling in Plants. TRENDS IN PLANT SCIENCE 2021; 26:452-471. [PMID: 33257259 DOI: 10.1016/j.tplants.2020.11.003] [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: 03/12/2020] [Revised: 10/12/2020] [Accepted: 11/03/2020] [Indexed: 06/12/2023]
Abstract
Metalloids are semiconducting elements that constitute a small group in the periodic table of elements. Their occurrence in nature either poses an environmental threat or benefit to plants. The precise mechanisms or manner of crosstalk of metalloid interference and sensing remain open questions. Standard plant nutrient solutions contain the metalloid boron (B) as a micronutrient, while silicon (Si) is considered a beneficial element routinely supplied only to some plants such as grasses. By contrast, arsenic (As) is a severe environmental hazard to most organisms, including plants, while the less abundant metalloids germanium (Ge), antimony (Sb), and tellurium (Te) display variable degrees of toxicity. Here we review the molecular events and mechanisms that could explain the contrasting (or overlapping) action of metalloids on the cell and cell signaling.
Collapse
Affiliation(s)
- Shanti S Sharma
- Department of Botany, School of Life Sciences, Sikkim University, Gangtok 737102, Sikkim, India
| | - Vijay Kumar
- Department of Biochemistry and Physiology of Plants, Faculty of Biology, University of Bielefeld, Bielefeld, Germany; Department of Biosciences, Himachal Pradesh University, Shimla 171005, India
| | - Karl-Josef Dietz
- Department of Biochemistry and Physiology of Plants, Faculty of Biology, University of Bielefeld, Bielefeld, Germany.
| |
Collapse
|
14
|
Monitoring Arsenic Species Content in Seaweeds Produced off the Southern Coast of Korea and Its Risk Assessment. ENVIRONMENTS 2020. [DOI: 10.3390/environments7090068] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Seaweed, a popular seafood in South Korea, has abundant dietary fiber and minerals. The toxicity of arsenic compounds is known to be related to their chemical speciation, and inorganic arsenic (iAs) is more detrimental than other species. Due to the different toxicities of the various chemical forms, speciation analysis is important for evaluating arsenic exposure. In this study, total arsenic (tAs) and six arsenic species (arsenite, arsenate, monomethylarsonic acid, dimethylarsinic acid, arsenobetaine, and arsenocholine) were analyzed in 180 seaweed samples. Although there were differences between seaweed species, the concentration of tAs was detected at levels ranging from 1 to 100 µg/g, and the distribution of six arsenic species differed depending on the seaweed species. No correlation between the concentration of iAs and tAs was found in most seaweed species. Through statistical clustering, hijiki and gulfweed were seen to be the seaweeds with the highest ratios of iAs to tAs. Using the iAs concentration data from the arsenic speciation analysis, a risk assessment of seaweed intake in South Korea was conducted. The margin of exposure values showed no meaningful risk for the general population, but low levels of risk were identified for seaweed consumers, with high intakes of gulfweed and hijiki.
Collapse
|
15
|
Wang J, Halder D, Wegner L, Brüggenwirth L, Schaller J, Martin M, Said-Pullicino D, Romani M, Planer-Friedrich B. Redox Dependence of Thioarsenate Occurrence in Paddy Soils and the Rice Rhizosphere. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:3940-3950. [PMID: 32182045 DOI: 10.1021/acs.est.9b05639] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In flooded paddy soils, inorganic and methylated thioarsenates contribute substantially to arsenic speciation besides the much-better-investigated oxyarsenic species, and thioarsenate uptake into rice plants has recently been shown. To better understand their fate when soil redox conditions change, that is, from flooding to drainage to reflooding, batch incubations and unplanted microcosm experiments were conducted with two paddy soils covering redox potentials from EH -260 to +200 mV. Further, occurrence of thioarsenates in the oxygenated rice rhizosphere was investigated using planted rhizobox experiments. Soil flooding resulted in rapid formation of inorganic thioarsenates with a dominance of trithioarsenate. Maximum thiolation of inorganic oxyarsenic species was 57% at EH -130 mV and oxidation caused nearly complete dethiolation. Only monothioarsenate formed again upon reflooding and was the major inorganic thioarsenate detected in the rhizosphere. Maximum thiolation of mono- and dimethylated oxyarsenates was about 70% and 100%, respectively, below EH 0 mV. Dithiolated species dominated over monothiolated species below EH -100 mV. Among all thioarsenates, dimethylated monothioarsenate showed the least transformation upon prolonged oxidation. It also was the major thiolated arsenic species in the rhizosphere with concentrations comparable to its precursor dimethylated oxyarsenate, which is especially critical since dimethylated monothioarsenate is highly carcinogenic.
Collapse
Affiliation(s)
- Jiajia Wang
- Department of Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany
| | - Dipti Halder
- Department of Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany
| | - Laura Wegner
- Department of Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany
| | - Lena Brüggenwirth
- Department of Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany
| | - Jörg Schaller
- Department of Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany
- Leibniz Center for Agricultural Landscape Research (ZALF), 15374 Müncheberg, Germany
| | - Maria Martin
- Department of Agriculture, Forest and Food Sciences, University of Turin, 10124 Turin, Italy
| | - Daniel Said-Pullicino
- Department of Agriculture, Forest and Food Sciences, University of Turin, 10124 Turin, Italy
| | - Marco Romani
- Rice Research Centre, Ente Nazionale Risi, 27030 Castello d'Agogna, Pavia Italy
| | - Britta Planer-Friedrich
- Department of Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany
| |
Collapse
|
16
|
McDermott TR, Stolz JF, Oremland RS. Arsenic and the gastrointestinal tract microbiome. ENVIRONMENTAL MICROBIOLOGY REPORTS 2020; 12:136-159. [PMID: 31773890 DOI: 10.1111/1758-2229.12814] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 11/23/2019] [Accepted: 11/25/2019] [Indexed: 06/10/2023]
Abstract
Arsenic is a toxin, ranking first on the Agency for Toxic Substances and Disease Registry and the Environmental Protection Agency Priority List of Hazardous Substances. Chronic exposure increases the risk of a broad range of human illnesses, most notably cancer; however, there is significant variability in arsenic-induced disease among exposed individuals. Human genetics is a known component, but it alone cannot account for the large inter-individual variability in the presentation of arsenicosis symptoms. Each part of the gastrointestinal tract (GIT) may be considered as a unique environment with characteristic pH, oxygen concentration, and microbiome. Given the well-established arsenic redox transformation activities of microorganisms, it is reasonable to imagine how the GIT microbiome composition variability among individuals could play a significant role in determining the fate, mobility and toxicity of arsenic, whether inhaled or ingested. This is a relatively new field of research that would benefit from early dialogue aimed at summarizing what is known and identifying reasonable research targets and concepts. Herein, we strive to initiate this dialogue by reviewing known aspects of microbe-arsenic interactions and placing it in the context of potential for influencing host exposure and health risks. We finish by considering future experimental approaches that might be of value.
Collapse
Affiliation(s)
- Timothy R McDermott
- Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT, 59717, USA
| | - John F Stolz
- Department of Biological Sciences and Center for Environmental Research and Education, Duquesne University, Pittsburgh, PA, USA
| | | |
Collapse
|
17
|
Kerl CF, Ballaran TB, Planer-Friedrich B. Iron Plaque at Rice Roots: No Barrier for Methylated Thioarsenates. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:13666-13674. [PMID: 31675232 DOI: 10.1021/acs.est.9b04158] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Iron (hydr)oxide coating at rice roots, so-called iron plaque (IP), is often an important barrier for uptake of inorganic oxyarsenic species and their accumulation in rice grains. Sorption of methylated thioarsenates, which can co-exist with inorganic and methylated oxyarsenates in paddy soils, was not studied yet, even though these toxic species were detected in xylem and grains of rice plants before. Hydroponic experiments at pH 6.5 with 20 day-old rice plants showed lower net arsenic enrichment in IP for plants exposed to monomethylthioarsenate (MMMTA) compared to monomethylarsenate (MMA) and no enrichment for dimethylmonothioarsenate (DMMTA). Goethite was the dominant mineral phase in our IP. Sorption experiments with synthesized goethite and ferrihydrite revealed a 30-times-higher sorption capacity for MMMTA to amorphous ferrihydrite than to crystalline goethite, comparable to methylated oxyarsenates. No evidence for direct MMMTA binding was found. Instead, we postulate that MMMTA transformation to MMA is a prerequisite for removal. DMMTA showed very little sorption, even to amorphous ferrihydrite, which is in line with a lack of direct binding and reported slow transformation to dimethylarsenate. Our study implies that IP is no effective barrier for methylated thioarsenates and that especially DMMTA is very mobile with a high risk of uptake in rice plants.
Collapse
|
18
|
Fan C, Liu G, Long Y, Rosen B, Cai Y. Thiolation in arsenic metabolism: a chemical perspective. Metallomics 2019; 10:1368-1382. [PMID: 30207373 DOI: 10.1039/c8mt00231b] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In recent years, methylated thioarsenicals have been widely detected in various biological and environmental matrices, suggesting their broad involvement and biological importance in arsenic metabolism. However, very little is known about the formation mechanism of methylated thioarsenicals and the relation between arsenic methylation and thiolation processes. It is timely and necessary to summarize and synthesize the reported information on thiolated arsenicals for an improved understanding of arsenic thiolation. To this end, we examined the proposed formation pathways of methylated oxoarsenicals and thioarsenicals from a chemical perspective and proposed a novel arsenic metabolic scheme, in which arsenic thiolation is integrated with methylation (instead of being separated from methylation as currently reported). We suggest in the new scheme that protein-bound pentavalent arsenicals are critical intermediates that connect methylation and thiolation, with protein binding of pentavalent methylated thioarsenical being a key step for arsenic thiolation. This informative review on arsenic thiolation from the chemical perspective will be helpful to better understand the arsenic metabolism at the molecular level and the toxicological effects of arsenic species.
Collapse
Affiliation(s)
- Changjun Fan
- Department of Chemistry & Biochemistry, Florida International University, 11200 SW 8th St, Miami, FL 33199, USA.
| | | | | | | | | |
Collapse
|
19
|
Kerl CF, Schindele RA, Brüggenwirth L, Colina Blanco AE, Rafferty C, Clemens S, Planer-Friedrich B. Methylated Thioarsenates and Monothioarsenate Differ in Uptake, Transformation, and Contribution to Total Arsenic Translocation in Rice Plants. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:5787-5796. [PMID: 31033272 DOI: 10.1021/acs.est.9b00592] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Methylated and inorganic thioarsenates have recently been reported from paddy fields besides the better-known oxyarsenates. Methylated thioarsenates are highly toxic for humans, yet their uptake, transformation, and translocation in rice plants is unknown. Here, hydroponic experiments with 20 day old rice plants showed that monomethylmonothioarsenate (MMMTA), dimethylmonothioarsenate (DMMTA), and monothioarsenate (MTA) were taken up by rice roots and could be detected in the xylem. Total arsenic (As) translocation from roots to shoots was higher for plants exposed to DMMTA, MTA, and dimethylarsenate (DMAV) compared to MMMTA and monomethylarsenate (MMAV). All thioarsenates were partially transformed in the presence of rice roots, but processes and extents differed. MMMTA was subject to abiotic oxidation and largely dethiolated to MMAV already outside the plant, probably due to root oxygen loss. DMMTA and MTA were not oxidized abiotically. Crude protein extracts showed rapid enzymatic reduction for MTA but not for DMMTA. Our study implies that DMMTA has the highest potential to contribute to total As accumulation in grains either as DMAV or partially as DMMTA. DMMTA has once been detected in rice grains using enzymatic extraction. By routine acid extraction, DMMTA is determined as DMAV and thus escapes regulation despite its toxicity.
Collapse
Affiliation(s)
- Carolin F Kerl
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER) , University of Bayreuth , D-95440 Bayreuth , Germany
| | - Ruth Alina Schindele
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER) , University of Bayreuth , D-95440 Bayreuth , Germany
| | - Lena Brüggenwirth
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER) , University of Bayreuth , D-95440 Bayreuth , Germany
| | - Andrea E Colina Blanco
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER) , University of Bayreuth , D-95440 Bayreuth , Germany
| | - Colleen Rafferty
- Plant Physiology, Bayreuth Center for Ecology and Environmental Research (BayCEER) , University of Bayreuth , D-95440 Bayreuth , Germany
| | - Stephan Clemens
- Plant Physiology, Bayreuth Center for Ecology and Environmental Research (BayCEER) , University of Bayreuth , D-95440 Bayreuth , Germany
| | - Britta Planer-Friedrich
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER) , University of Bayreuth , D-95440 Bayreuth , Germany
| |
Collapse
|
20
|
Herath I, Vithanage M, Seneweera S, Bundschuh J. Thiolated arsenic in natural systems: What is current, what is new and what needs to be known. ENVIRONMENT INTERNATIONAL 2018; 115:370-386. [PMID: 29705693 DOI: 10.1016/j.envint.2018.03.027] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 03/15/2018] [Accepted: 03/18/2018] [Indexed: 06/08/2023]
Abstract
Thiolated arsenic compounds are the sulfur analogous substructures of oxo-arsenicals as the arsinoyl (As = O) is substituted by an arsinothioyl (As = S) group. Relatively brief history of thioarsenic research, mostly in the current decade has endeavored to understand their consequences in the natural environment. However, thioarsenic related aspects have by far not attached much research concern on global scale compared to other arsenic species. This review attempts to provide a critical overview for the first time on formation mechanisms of thioarsenicals, their chemistry, speciation and analytical methodologies in order to provide a rational assessment of what is new, what is current, what needs to be known or what should be done in future research. Thioarsenic compounds play a vital role in determining the biogeochemistry of arsenic in sulfidic environments under reducing conditions. Thioarsenic species are widely immobilized by naturally occurring processes such as the adsorption on iron (oxyhydr)oxides and precipitation on iron sulfide minerals. Accurate measurement of thioarsenic species is a challenging task due to their instability upon pH, temperature, redox potential, and concentrations of oxygen, sulfur and iron. Assessment of direct and indirect effects of toxic thioarsenic species on global population those who frequently get exposed to high levels of arsenic is an urgent necessity. Dimethylmonothioarsinic acid (DMMTAV) is the most cytotoxic arsenic metabolite having similar toxicological effects as dimethylarsinous acid (DMAIII) in human and animal tissues. The formation and chemical analysis of thioarsenicals in soil and sediments are highly unknown. Therefore, future research needs to be more inclined towards in determining the molecular structure of unknown thioarsenic complexes in various environmental suites. Contemporary approaches hyphenated to existing technologies would pave the way to overcome critical challenges of thioarsenic speciation such as standards synthesis, structural determination, quantification and sample preservation in future research.
Collapse
Affiliation(s)
- Indika Herath
- School of Civil Engineering and Surveying, Faculty of Health, Engineering and Sciences, University of Southern Queensland, West Street, 4350 Toowoomba, Queensland, Australia
| | - Meththika Vithanage
- International Centre for Applied Climate Science, University of Southern Queensland, West Street, Toowoomba, 4350, Queensland, Australia; Faculty of Applied Sciences, University of Sri Jayewardenepura, Nugegoda 10250, Sri Lanka
| | - Saman Seneweera
- Plant Stress Biology Research Group, Centre for Crop Health, University of Southern Queensland, West Street, Toowoomba, 4350, Queensland, Australia
| | - Jochen Bundschuh
- School of Civil Engineering and Surveying, Faculty of Health, Engineering and Sciences, University of Southern Queensland, West Street, 4350 Toowoomba, Queensland, Australia; UNESCO Chair on Groundwater Arsenic within the 2030 Agenda for Sustainable Development, University of Southern Queensland, West Street, 4350 Toowoomba, Queensland, Australia.
| |
Collapse
|
21
|
Lee H, Kim YT, Jeong S, Yoon HO. Preparation of DMMTAV and DMDTAV Using DMAV for Environmental Applications: Synthesis, Purification, and Confirmation. J Vis Exp 2018. [PMID: 29578528 DOI: 10.3791/56603] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Dimethylated thioarsenicals such as dimethylmonothioarsinic acid (DMMTAV) and dimethyldithioarsinic acid (DMDTAV), which are produced by the metabolic pathway of dimethylarsinic acid (DMAV) thiolation, have been recently found in the environment as well as human organs. DMMTAV and DMDTAV can be quantified to determine the ecological effects of dimethylated thioarsenicals and their stability in environmental media. The synthesis method for these compounds is unstandardized, making replicating previous studies challenging. Furthermore, there is a lack of information about storage techniques, including storage of compounds without species transformation. Moreover, because only limited information about synthesis methods is available, there may be experimental difficulties in synthesizing standard chemicals and performing quantitative analysis. The protocol presented herein provides a practically modified synthesis method for the dimethylated thioarsenicals, DMMTAV and DMDTAV, and will help in the quantification of species separation analysis using high performance liquid chromatography in conjunction with inductively coupled plasma mass spectrometry (HPLC-ICP-MS). The experimental steps of this procedure were modified by focusing on the preparation of chemical reagents, filtration methods, and storage.
Collapse
Affiliation(s)
- Hosub Lee
- Korea Basic Science Institute, Seoul Center
| | - Youn-Tae Kim
- Natural Science Research Institute, Yonsei University
| | | | - Hye-On Yoon
- Korea Basic Science Institute, Seoul Center;
| |
Collapse
|
22
|
Jeong S, Lee H, Kim YT, Yoon HO. Development of a simultaneous analytical method to determine arsenic speciation using HPLC-ICP-MS: Arsenate, arsenite, monomethylarsonic acid, dimethylarsinic acid, dimethyldithioarsinic acid, and dimethylmonothioarsinic acid. Microchem J 2017. [DOI: 10.1016/j.microc.2017.06.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
|