1
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Colina Blanco AE, Higa Mori A, Planer-Friedrich B. Widespread occurrence of dimethylmonothioarsenate (DMMTA) in rice cakes: Effects of puffing and storage. Food Chem 2024; 436:137723. [PMID: 37862982 DOI: 10.1016/j.foodchem.2023.137723] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 09/29/2023] [Accepted: 10/08/2023] [Indexed: 10/22/2023]
Abstract
Thioarsenates have recently been detected in rice and rice-based products, with particularly high contents in puffed rice cakes. Here, we show that puffing rice can cause almost complete transformation of dimethylarsenate (DMA) to dimethyldithioarsenate (DMDTA) and dimethylmonothioarsenate (DMMTA). Analysis of puffed rice cakes after 3 months of non-sealed storage at room temperature showed transformation of DMDTA mainly into DMMTA. From a food safety perspective, this likely represents an increased risk because DMMTA is highly cytotoxic and misidentified as non-regulated DMA by routine acid extractions. Analysis of 80 commercial puffed rice cakes confirmed widespread occurrence of thioarsenates. The sum of non-regulated, but potentially toxic DMMTA and DMDTA reached values up to 537 µg·kg-1 and 241 µg·kg-1 for generic and infant-labeled rice cakes, respectively. Our results highlight the importance of better understanding (de)thiolation processes along the rice cake-production chain and potentially revising current thresholds set for iAs to include DMMTA and DMDTA.
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Affiliation(s)
- Andrea E Colina Blanco
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany.
| | - Alejandra Higa Mori
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany.
| | - Britta Planer-Friedrich
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany.
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2
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Gokulan K, Mathur A, Kumar A, Vanlandingham MM, Khare S. Route of Arsenic Exposure Differentially Impacts the Expression of Genes Involved in Gut-Mucosa-Associated Immune Responses and Gastrointestinal Permeability. Int J Mol Sci 2023; 24:ijms24076352. [PMID: 37047323 PMCID: PMC10094558 DOI: 10.3390/ijms24076352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/09/2023] [Accepted: 03/11/2023] [Indexed: 03/30/2023] Open
Abstract
First-pass metabolism alters arsenic biotransformation and its immunomodulatory activities. This study aims to determine the mRNA expression of intestinal-immunity- and permeability-associated genes, levels of cytokine/chemokines and levels of immunoglobulin isotypes when CD-1 mice were exposed to a single dose of intravenous (IV) sodium arsenite (50 µg/kg body weight (BW)) and to compare these responses to exposure via oral gavage (OG) (50 µg/kg BW). Samples were collected at 1, 4, 24 and 48 h post IV exposure and 24 and 48 h post OG. Sodium arsenite IV exposure led to a transient modulation of mRNA expression and protein levels of immunity-related genes involved in inflammation/apoptotic pathways and production of cytokines/chemokines, whereas it also led to downregulated expression of genes encoding tight junction, focal adhesion, and gap junction proteins, which are responsible for maintaining cell permeability. Oral exposure perturbed fewer cell-permeability-related genes at 24 and 48 h post exposure. At 24 h post exposure, OG decreased IgA and IgG2b levels; however, IV exposure significantly increased IgG2b, IgG3 and IgA in ileal tissue. Earlier, we showed significant downregulation of mRNA expression of genes involved in the immune-related pathways during OG in the intestinal mucosa of the same animals. Cumulatively, these results provide evidence that the exposure route of a xenobiotic can differentially impact the intestinal responses due to the impact of first-pass metabolism.
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Affiliation(s)
- Kuppan Gokulan
- Division of Microbiology, National Center for Toxicological Research, US Food and Drug Administration, 3900 NCTR Rd, Jefferson, AR 72079, USA
| | - Aakriti Mathur
- Division of Microbiology, National Center for Toxicological Research, US Food and Drug Administration, 3900 NCTR Rd, Jefferson, AR 72079, USA
| | - Amit Kumar
- Division of Microbiology, National Center for Toxicological Research, US Food and Drug Administration, 3900 NCTR Rd, Jefferson, AR 72079, USA
| | - Michelle M. Vanlandingham
- Division of Biochemical Toxicology, National Center for Toxicological Research, US Food and Drug Administration, 3900 NCTR Rd, Jefferson, AR 72079, USA
| | - Sangeeta Khare
- Division of Microbiology, National Center for Toxicological Research, US Food and Drug Administration, 3900 NCTR Rd, Jefferson, AR 72079, USA
- Correspondence: ; Tel.: +1-870-543-7519
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3
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Planer-Friedrich B, Kerl CF, Colina Blanco AE, Clemens S. Dimethylated Thioarsenates: A Potentially Dangerous Blind Spot in Current Worldwide Regulatory Limits for Arsenic in Rice. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:9610-9618. [PMID: 35901520 DOI: 10.1021/acs.jafc.2c02425] [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] [Indexed: 06/15/2023]
Abstract
Arsenic (As) occurrence in rice is a serious human health threat. Worldwide, regulations typically limit only carcinogenic inorganic As, but not possibly carcinogenic dimethylated oxyarsenate (DMA). However, there is emerging evidence that "DMA", determined by routine acid-based extraction and analysis, hides a substantial share of dimethylated thioarsenates that have similar or higher cytotoxicities than arsenite. Risk assessments characterizing the in vivo toxicity of rice-derived dimethylated thioarsenates are urgently needed. In the meantime, either more sophisticated methods based on enzymatic extraction and separation of dimethylated oxy- and thioarsenates have to become mandatory or total As should be regulated.
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Affiliation(s)
- Britta Planer-Friedrich
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, D-95440 Bayreuth, Germany
| | - Carolin F Kerl
- 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
| | - Stephan Clemens
- Plant Physiology, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, D-95440 Bayreuth, Germany
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4
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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.
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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
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Dai J, Tang Z, Gao AX, Planer-Friedrich B, Kopittke PM, Zhao FJ, Wang P. Widespread Occurrence of the Highly Toxic Dimethylated Monothioarsenate (DMMTA) in Rice Globally. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:3575-3586. [PMID: 35174706 DOI: 10.1021/acs.est.1c08394] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Arsenic (As) accumulation in rice is of global concern for human health and international trade. Rice is typically reported to contain inorganic As (iAs) and dimethylated arsenate (DMA), with current food guidelines limiting toxic iAs but not less-toxic DMA. Here, we show that the highly toxic dimethylated monothioarsenate (DMMTA) is also found in rice worldwide and has been unknowingly determined as less-toxic DMA by previous routine analytical methods. Using enzymatic extraction followed by high-performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) analysis with a C18 column, DMMTA was detected in rice grains (n = 103) from a field survey from China and in polished rice grains (n = 140) from a global market-basket survey. Concentration ranged from <0.20 to 34.8 μg/kg (median 10.3 μg/kg), accounting for 0 to 21% of total As. A strong linear correlation was observed in all rice samples between DMA and DMMTA (being 30 ± 8% of DMA) concentrations. This robust relationship allows an estimation of DMMTA in rice grains from the DMA data reported in previous market-basket surveys, showing a general global geographical pattern with DMMTA concentration increasing from the equator toward high-latitude regions. Based on the global occurrence and potential high toxicity, DMMTA in rice should be considered in health risk assessments and for setting food regulations.
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Affiliation(s)
- Jun Dai
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China
| | - Zhu Tang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China
| | - A-Xiang Gao
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China
| | - Britta Planer-Friedrich
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth D-95447, Germany
| | - Peter M Kopittke
- School of Agriculture and Food Sciences, The University of Queensland, St Lucia 4072, Queensland, Australia
| | - Fang-Jie Zhao
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China
| | - Peng Wang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China
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6
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Colina Blanco AE, Kerl CF, Planer-Friedrich B. Detection of Thioarsenates in Rice Grains and Rice Products. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:2287-2294. [PMID: 33566616 DOI: 10.1021/acs.jafc.0c06853] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Inorganic and methylated thioarsenates have recently been reported to contribute substantially to arsenic (As) speciation in paddy-soil pore waters. Here, we show that thioarsenates can also accumulate in rice grains and rice products. For their detection, a method was developed using a pepsin-pancreatin enzymatic extraction followed by chromatographic separation at pH 13. From 54 analyzed commercial samples, including white, parboiled and husked rice, puffed rice cakes, and rice flakes, 50 contained dimethylmonothioarsenate (DMMTA) (maximum 25.6 μg kg-1), 18 monothioarsenate (MTA) (maximum 5.6 μg kg-1), 14 dimethyldithioarsenate (DMDTA) (maximum 2.8 μg kg-1), and 5 dithioarsenate (DTA) (maximum 2.3 μg kg-1). Additionally, we show that the commonly used nitric acid extraction transforms MTA to arsenite and DMMTA and DMDTA to dimethylarsenate (DMA). Current food guidelines do not require an analysis of thioarsenates in rice and only limit the contents of inorganic oxyarsenic species (including acid-extraction-transformed MTA), but not DMA (including acid-extraction-transformed DMMTA and DMDTA).
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Affiliation(s)
- Andrea E Colina Blanco
- Department of Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany
| | - Carolin F Kerl
- Department of Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany
| | - Britta Planer-Friedrich
- Department of Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany
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7
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Feng W, Liu J, Huang L, Tan Y, Peng C. Gut microbiota as a target to limit toxic effects of traditional Chinese medicine: Implications for therapy. Biomed Pharmacother 2020; 133:111047. [PMID: 33378954 DOI: 10.1016/j.biopha.2020.111047] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 11/11/2020] [Accepted: 11/19/2020] [Indexed: 12/17/2022] Open
Abstract
Traditional Chinese medicines (TCMs) are medicines that are widely used in oriental countries under the guidance of ancient Chinese medicinal philosophies. With thousands of years of experiences in fighting against diseases, TCMs are gaining increasing importance in the world. Although the efficacy of TCMs is well recognized in clinic, the toxicity of TCMs has become a serious issue around the world in recent years. In general, the toxicity of TCMs is caused by the toxic medicinal compounds and contaminants in TCMs such as pesticides, herbicides, and heavy metals. Recent studies have demonstrated that gut microbiota can interact with TCMs and thus influence the toxicity of TCMs. However, there is no focused review on gut microbiota and the toxicity of TCMs. Here, we summarized the influences of the gut microbiota on the toxicity of medicinal compounds in TCMs and the corresponding mechanisms were offered. Then, we discussed the relationships between gut microbiota and the TCM contaminants. In addition, we discussed the methods of manipulating gut microbiota to reduce the toxicity of TCMs. At the end of this review, the perspectives on gut microbiota and the toxicity of TCMs were also discussed.
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Affiliation(s)
- Wuwen Feng
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, China; State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Juan Liu
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Lihua Huang
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, China; State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Yuzhu Tan
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, China; State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Cheng Peng
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, China; State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Chengdu University of Traditional Chinese Medicine, Chengdu, China.
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8
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Feng W, Liu J, Ao H, Yue S, Peng C. Targeting gut microbiota for precision medicine: Focusing on the efficacy and toxicity of drugs. Theranostics 2020; 10:11278-11301. [PMID: 33042283 PMCID: PMC7532689 DOI: 10.7150/thno.47289] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 08/20/2020] [Indexed: 02/06/2023] Open
Abstract
Intra- and interindividual variation in drug responses is one major reason for the failure of drug therapy, drug toxicity, and even the death of patients. Precision medicine, or personalized medicine, is a field of medicine that customizes an individual's medical diagnosis and treatment based on his/her genes, microbiomes, environments, etc. Over the past decade, a large number of studies have demonstrated that gut microbiota can modify the efficacy and toxicity of drugs, and the extent of the modification varies greatly from person to person because of the variability of the gut microbiota. Personalized manipulation of gut microbiota is an important approach to rectify the abnormal drug response. In this review, we aim to improve drug efficacy and reduce drug toxicity by combining precision medicine and gut microbiota. After describing the interactions between gut microbiota and xenobiotics, we discuss (1) the effects of gut microbiota on drug efficacy and toxicity and the corresponding mechanisms, (2) the variability of gut microbiota, which leads to variation in drug responses, (3) the biomarkers used for the patient stratification and treatment decisions before the use of drugs, and (4) the methods used for the personalized manipulation of gut microbiota to improve drug outcomes. Overall, we hope to improve the drug response by incorporating the knowledge of gut microbiota into clinical practice.
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Affiliation(s)
- Wuwen Feng
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, China
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Juan Liu
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Hui Ao
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Shijun Yue
- Shaanxi Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Shaanxi University of Chinese Medicine, Xi'an, China
| | - Cheng Peng
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, China
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, China
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9
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Chi H, Hou Y, Li G, Zhang Y, Coulon F, Cai C. In vitro model insights into the role of human gut microbiota on arsenic bioaccessibility and its speciation in soils. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 263:114580. [PMID: 33618458 DOI: 10.1016/j.envpol.2020.114580] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 03/15/2020] [Accepted: 04/09/2020] [Indexed: 06/12/2023]
Abstract
The bioaccessibility of arsenic and its speciation are two important factors in assessing human health risks exposure to contaminated soils. However, the effects of human gut microbiota on arsenic bioaccessibility and its speciation are not well characterized. In this study, an improved in vitro model was utilized to investigate the bioaccessibility of arsenic in the digestive tract and the role of human gut microbiota in the regulation of arsenic speciation. For all soils, arsenic bioaccessibility from the combined in vitro model showed that it was <40% in the gastric, small intestinal and colon phases. This finding demonstrated that the common bioaccessibility approach assuming 100% bioaccessibility would overestimate the human health risks posed by contaminated soils. Further to this, the study showed that arsenic bioaccessibility was 22% higher in the active colon phase than that in the sterile colon phase indicating that human colon microorganisms could induce arsenic release from the solid phase. Only inorganic arsenic was detected in the gastric and small intestinal phases, with arsenate [As(V)] being the dominant arsenic species (74%-87% of total arsenic). Arsenic speciation was significantly altered by the active colon microbiota, which resulted in the formation of methylated arsenic species, including monomethylarsonic acid [MMA(V)] and dimethylarsinic acid [DMA(V)] with low toxicity, and a highly toxic arsenic species monomethylarsonous acid [MMA(III)]. Additionally, a high level of monomethylmonothioarsonic acid [MMMTA(V)] (up to 17% of total arsenic in the extraction solution) with unknown toxicological properties was also detected in the active colon phase. The formation of various organic arsenic species demonstrated that human colon microorganisms could actively metabolize inorganic arsenic into methylated arsenicals and methylated thioarsenicals. Such transformation should be considered when assessing the human health risks associated with oral exposure to soil.
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Affiliation(s)
- Haifeng Chi
- State Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yanwei Hou
- Department of Environmental Science and Engineering, Huaqiao University, Xiamen, 361021, China
| | - Guofeng Li
- State Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Youchi Zhang
- State Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China
| | - Frédéric Coulon
- School of Water, Energy and Environment, Cranfield University, Cranfield, MK43 0AL, UK
| | - Chao Cai
- State Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.
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10
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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.
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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
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11
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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.
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12
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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.
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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
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13
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Redox metabolism of ingested arsenic: Integrated activities of microbiome and host on toxicological outcomes. CURRENT OPINION IN TOXICOLOGY 2019. [DOI: 10.1016/j.cotox.2018.09.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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14
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Blum JS, Hernandez-Maldonado J, Redford K, Sing C, Bennett SC, Saltikov CW, Oremland RS. Arsenate-dependent growth is independent of an ArrA mechanism of arsenate respiration in the termite hindgut isolate Citrobacter sp. strain TSA-1. Can J Microbiol 2018; 64:619-627. [PMID: 30169127 DOI: 10.1139/cjm-2017-0523] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Citrobacter sp. strain TSA-1 is an enteric bacterium isolated from the hindgut of the termite. Strain TSA-1 displays anaerobic growth with selenite, fumarate, tetrathionate, nitrate, or arsenate serving as electron acceptors, and it also grows aerobically. In regards to arsenate, genome sequencing revealed that strain TSA-1 lacks a homolog for respiratory arsenate reductase, arrAB, and we were unable to obtain amplicons of arrA. This raises the question as to how strain TSA-1 achieves As(V)-dependent growth. We show that growth of strain TSA-1 on glycerol, which it cannot ferment, is linked to the electron acceptor arsenate. A series of transcriptomic experiments were conducted to discern which genes were upregulated during growth on arsenate, as opposed to those on fumarate or oxygen. For As(V), upregulation was noted for 1 of the 2 annotated arsC genes, while there was no clear upregulation for tetrathionate reductase (ttr), suggesting that this enzyme is not an alternative to arrAB as occurs in certain hyperthermophilic archaea. A gene-deletion mutant strain of TSA-1 deficient in arsC could not achieve anaerobic respiratory growth on As(V). Our results suggest that Citrobacter sp. strain TSA-1 has an unusual and as yet undefined means of achieving arsenate respiration, perhaps involving its ArsC as a respiratory reductase as well as a detoxifying agent.
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Affiliation(s)
- Jodi Switzer Blum
- a National Research Program-Western Branch, Water Mission Area, US Geological Survey, Menlo Park, California, USA
| | - Jaime Hernandez-Maldonado
- b Division of Microbiology and Environmental Toxicology, University of California, Santa Cruz, Santa Cruz, California, USA
| | - Kaitlyn Redford
- b Division of Microbiology and Environmental Toxicology, University of California, Santa Cruz, Santa Cruz, California, USA
| | - Caitlyn Sing
- b Division of Microbiology and Environmental Toxicology, University of California, Santa Cruz, Santa Cruz, California, USA
| | - Stacy C Bennett
- a National Research Program-Western Branch, Water Mission Area, US Geological Survey, Menlo Park, California, USA
| | - Chad W Saltikov
- b Division of Microbiology and Environmental Toxicology, University of California, Santa Cruz, Santa Cruz, California, USA
| | - Ronald S Oremland
- a National Research Program-Western Branch, Water Mission Area, US Geological Survey, Menlo Park, California, USA.,b Division of Microbiology and Environmental Toxicology, University of California, Santa Cruz, Santa Cruz, California, USA
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15
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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.
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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.
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16
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Planer-Friedrich B, Schaller J, Wismeth F, Mehlhorn J, Hug SJ. Monothioarsenate Occurrence in Bangladesh Groundwater and Its Removal by Ferrous and Zero-Valent Iron Technologies. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:5931-5939. [PMID: 29671316 DOI: 10.1021/acs.est.8b00948] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In most natural groundwaters, sulfide concentrations are low, and little attention has been paid to potential occurrence of thioarsenates (AsVS n-IIO4- n3- with n = 1-4). Thioarsenate occurrence in groundwater could be critical with regard to the efficiency of iron (Fe)-based treatment technologies because previous studies reported less sorption of thioarsenates to preformed Fe-minerals compared to arsenite and arsenate. We analyzed 273 groundwater samples taken from different wells in Bangladesh over 1 year and detected monothioarsenate (MTA), likely formed via solid-phase zero-valent sulfur, in almost 50% of all samples. Concentrations ranged up to >30 μg L-1 (21% of total As). MTA removal by locally used technologies in which zero-valent or ferrous Fe is oxidized by aeration and As sorbs or coprecipitates with the forming Fe(III)hydroxides was indeed lower than for arsenate. The presence of phosphate required up to three times as much Fe(II) for comparable MTA removal. However, in contrast to previous sorption studies on preformed Fe minerals, MTA removal, even in the presence of phosphate, was still higher than that of arsenite. The more efficient MTA removal is likely caused by a combination of coprecipitation and adsorption rendering the tested Fe-based treatment technologies suitable for As removal also in the presence of MTA.
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Affiliation(s)
- Britta Planer-Friedrich
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER) , Bayreuth University , Universitaetsstrasse 30 , 95440 Bayreuth , Germany
| | - Jörg Schaller
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER) , Bayreuth University , Universitaetsstrasse 30 , 95440 Bayreuth , Germany
| | - Fabian Wismeth
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER) , Bayreuth University , Universitaetsstrasse 30 , 95440 Bayreuth , Germany
| | - Judith Mehlhorn
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER) , Bayreuth University , Universitaetsstrasse 30 , 95440 Bayreuth , Germany
| | - Stephan J Hug
- Eawag , Swiss Federal Institute for Environmental Science and Technology , Ueberlandstrasse 133 , 8600 Duebendorf , Switzerland
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17
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Ponomarenko O, La Porte PF, Singh SP, Langan G, Fleming DEB, Spallholz JE, Alauddin M, Ahsan H, Ahmed S, Gailer J, George GN, Pickering IJ. Selenium-mediated arsenic excretion in mammals: a synchrotron-based study of whole-body distribution and tissue-specific chemistry. Metallomics 2017; 9:1585-1595. [PMID: 29058732 DOI: 10.1039/c7mt00201g] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
Arsenicosis, a syndrome caused by ingestion of arsenic contaminated drinking water, currently affects millions of people in South-East Asia and elsewhere. Previous animal studies revealed that the toxicity of arsenite essentially can be abolished if selenium is co-administered as selenite. Although subsequent studies have provided some insight into the biomolecular basis of this striking antagonism, many details of the biochemical pathways that ultimately result in the detoxification and excretion of arsenic using selenium supplements have yet to be thoroughly studied. To this end and in conjunction with the recent Phase III clinical trial "Selenium in the Treatment of Arsenic Toxicity and Cancers", we have applied synchrotron X-ray techniques to elucidate the mechanisms of this arsenic-selenium antagonism at the tissue and organ levels using an animal model. X-ray fluorescence imaging (XFI) of cryo-dried whole-body sections of laboratory hamsters that had been injected with arsenite, selenite, or both chemical species, provided insight into the distribution of both metalloids 30 minutes after treatment. Co-treated animals showed strong co-localization of arsenic and selenium in the liver, gall bladder and small intestine. X-ray absorption spectroscopy (XAS) of freshly frozen organs of co-treated animals revealed the presence in liver tissues of the seleno bis-(S-glutathionyl) arsinium ion, which was rapidly excreted via bile into the intestinal tract. These results firmly support the previously postulated hepatobiliary excretion of the seleno bis-(S-glutathionyl) arsinium ion by providing the first data pertaining to organs of whole animals.
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Affiliation(s)
- Olena Ponomarenko
- Molecular and Environmental Science Research Group, Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada.
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18
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Yin N, Du H, Wang P, Cai X, Chen P, Sun G, Cui Y. Interindividual variability of soil arsenic metabolism by human gut microbiota using SHIME model. CHEMOSPHERE 2017; 184:460-466. [PMID: 28618278 DOI: 10.1016/j.chemosphere.2017.06.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 05/17/2017] [Accepted: 06/05/2017] [Indexed: 06/07/2023]
Abstract
Arsenic (As) metabolism by human gut microbiota has been evidenced with in vitro experiments from contaminated soils. In this study, the variability in the metabolic potency toward As-contaminated soils and gut microbial diversity were investigated between healthy individuals (Adult versus Child). Arsenic bioaccessibility in the colon phase increased by 1.4-6.8 and 1.2-8.7 folds for adult and child, respectively. We found a high degree of As methylation for the colon digests of the adult (mean 2 μg methylarsenicals/hr/g biomass), 3-folds higher than that of the child. Besides, arsenite [As(III)] concentration (1.5-391.3 μg/L) for the child was 2-18 times for the adult. 16S rRNA gene sequencing revealed that human gut microbiota from 20 various genera potentially had resistance genes to reduce and methylate As under conservative statistics. Our results indicated that As metabolism by gut microbiota from adult and child was significantly different. The adult gut microbiota had a great ability of As methylation; the child gut microbiota exhibited high As(III) level, which could encounter high health risk. The identity and activity of arsenic-metabolizing bacteria isolated from human gut and its homologous role in As metabolism need be further explored. This study provides a better understanding of health risk assessment to adults and children upon soil As exposures.
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Affiliation(s)
- Naiyi Yin
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-Environment Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Huili Du
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-Environment Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Pengfei Wang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-Environment Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Xiaolin Cai
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-Environment Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Peng Chen
- Research Center for Eco-Environment Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Guoxin Sun
- Research Center for Eco-Environment Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Yanshan Cui
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China; Research Center for Eco-Environment Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China.
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19
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Wu G, Huang L, Jiang H, Peng Y, Guo W, Chen Z, She W, Guo Q, Dong H. Thioarsenate Formation Coupled with Anaerobic Arsenite Oxidation by a Sulfate-Reducing Bacterium Isolated from a Hot Spring. Front Microbiol 2017; 8:1336. [PMID: 28769902 PMCID: PMC5509915 DOI: 10.3389/fmicb.2017.01336] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Accepted: 06/30/2017] [Indexed: 11/18/2022] Open
Abstract
Thioarsenates are common arsenic species in sulfidic geothermal waters, yet little is known about their biogeochemical traits. In the present study, a novel sulfate-reducing bacterial strain Desulfotomaculum TC-1 was isolated from a sulfidic hot spring in Tengchong geothermal area, Yunnan Province, China. The arxA gene, encoding anaerobic arsenite oxidase, was successfully amplified from the genome of strain TC-1, indicating it has a potential ability to oxidize arsenite under anaerobic condition. In anaerobic arsenite oxidation experiments inoculated with strain TC-1, a small amount of arsenate was detected in the beginning but became undetectable over longer time. Thioarsenates (AsO4-xSx2- with x = 1-4) formed with mono-, di- and tri-thioarsenates being dominant forms. Tetrathioarsenate was only detectable at the end of the experiment. These results suggest that thermophilic microbes might be involved in the formation of thioarsenates and provide a possible explanation for the widespread distribution of thioarsenates in terrestrial geothermal environments.
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Affiliation(s)
- Geng Wu
- State Key Laboratory of Biogeology and Environmental Geology, China University of GeosciencesWuhan, China
| | - Liuqin Huang
- State Key Laboratory of Biogeology and Environmental Geology, China University of GeosciencesWuhan, China
| | - Hongchen Jiang
- State Key Laboratory of Biogeology and Environmental Geology, China University of GeosciencesWuhan, China
| | - Yue’e Peng
- State Key Laboratory of Biogeology and Environmental Geology, China University of GeosciencesWuhan, China
| | - Wei Guo
- State Key Laboratory of Biogeology and Environmental Geology, China University of GeosciencesWuhan, China
| | - Ziyu Chen
- State Key Laboratory of Biogeology and Environmental Geology, China University of GeosciencesWuhan, China
| | - Weiyu She
- State Key Laboratory of Biogeology and Environmental Geology, China University of GeosciencesWuhan, China
| | - Qinghai Guo
- State Key Laboratory of Biogeology and Environmental Geology, China University of GeosciencesWuhan, China
| | - Hailiang Dong
- State Key Laboratory of Biogeology and Environmental Geology, China University of GeosciencesBeijing, China
- Department of Geology and Environmental Earth Science, Miami University, OxfordOH, United States
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20
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Planer-Friedrich B, Kühnlenz T, Halder D, Lohmayer R, Wilson N, Rafferty C, Clemens S. Thioarsenate Toxicity and Tolerance in the Model System Arabidopsis thaliana. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:7187-7196. [PMID: 28525265 DOI: 10.1021/acs.est.6b06028] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Thioarsenates form from arsenite under sulfate-reducing conditions, e.g., in rice paddy soils, and are structural analogues of arsenate. Even though rice is one of the most important sources of human arsenic intake, nothing is published about uptake, toxicity, or tolerance of thioarsenates in plants. Experiments using the model system Arabidopsis thaliana showed that monothioarsenate is less toxic than arsenite, but more toxic than arsenate at concentrations ≥25 μM As, reflected in stronger seedling growth inhibition on agar plates. Despite higher toxicity, total As accumulation in roots was lower upon exposure to monothioarsenate compared to arsenate, and a higher root efflux was confirmed. Root-shoot translocation was higher for monothioarsenate than for arsenate. Compared to the wild type (Col-0), both arsenate and monothioarsenate induced higher toxicity in phytochelatin (PC)-deficient mutants (cad1-3) as well as in glutathione biosynthesis (cad2) and PC transport (abcc12) mutants, demonstrating the important role of the PC pathway, not only for arsenate, but also for monothioarsenate detoxification. In Col-0, monothioarsenate induced relatively higher accumulation of PCs than arsenate. The observed differences in plant uptake, toxicity, and tolerance of thioarsenate vs oxyarsenate show that studying the effects of As on plants should include experiments with thiolated As species.
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Affiliation(s)
- Britta Planer-Friedrich
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), and ‡Department of Plant Physiology, University of Bayreuth , Universitätsstrasse 30, 95447 Bayreuth, Germany
| | - Tanja Kühnlenz
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), and ‡Department of Plant Physiology, University of Bayreuth , Universitätsstrasse 30, 95447 Bayreuth, Germany
| | - Dipti Halder
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), and ‡Department of Plant Physiology, University of Bayreuth , Universitätsstrasse 30, 95447 Bayreuth, Germany
| | - Regina Lohmayer
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), and ‡Department of Plant Physiology, University of Bayreuth , Universitätsstrasse 30, 95447 Bayreuth, Germany
| | - Nathaniel Wilson
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), and ‡Department of Plant Physiology, University of Bayreuth , Universitätsstrasse 30, 95447 Bayreuth, Germany
| | - Colleen Rafferty
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), and ‡Department of Plant Physiology, University of Bayreuth , Universitätsstrasse 30, 95447 Bayreuth, Germany
| | - Stephan Clemens
- Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), and ‡Department of Plant Physiology, University of Bayreuth , Universitätsstrasse 30, 95447 Bayreuth, Germany
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21
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Yin N, Cai X, Du H, Zhang Z, Li Z, Chen X, Sun G, Cui Y. In vitro study of soil arsenic release by human gut microbiota and its intestinal absorption by Caco-2 cells. CHEMOSPHERE 2017; 168:358-364. [PMID: 27810535 DOI: 10.1016/j.chemosphere.2016.10.091] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 10/20/2016] [Accepted: 10/24/2016] [Indexed: 06/06/2023]
Abstract
Arsenic (As) speciation is essential in assessing health risks from As-contaminated soil. Release of soil-bound arsenic, As transformation by human gut microbiota, and the subsequent intestinal absorption of soil As metabolites were evaluated. A colon microbial community in a dynamic human gut model and the intestinal epithelial cell line Caco-2 were cultured. Arsenic speciation analysis and absorption of different As species were undertaken. In this study, soil As release (3.7-581.2 mg kg-1) was observed in the colon. Arsenic in the colon digests was transformed more quickly than that in the soil solid phase. X-ray absorption near-edge spectroscopy (XANES) analysis showed that 44.2-97.6% of arsenite [As(III)] generated due to arsenate [As(V)] reduction was in the soil solid phase after the colon phase. We observed a high degree of cellular absorption of soil As metabolites, exhibiting that the intestinal absorption of monomethylarsonic acid and As(III) (33.6% and 30.2% resp.) was slightly higher than that of dimethylarsinic acid and As(V) (25.1% and 21.7% resp.). Our findings demonstrate that human gut microbiota can directly release soil-bound arsenic, particularly As-bearing amorphous Fe/Al-oxides. Determining As transformation and intestinal absorption simultaneously will result in an accurate risk assessment of human health with soil As exposures.
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Affiliation(s)
- Naiyi Yin
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 101408, People's Republic of China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, People's Republic of China
| | - Xiaolin Cai
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 101408, People's Republic of China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, People's Republic of China
| | - Huili Du
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 101408, People's Republic of China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, People's Republic of China
| | - Zhennan Zhang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 101408, People's Republic of China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, People's Republic of China
| | - Zejiao Li
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 101408, People's Republic of China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, People's Republic of China
| | - Xiaochen Chen
- College of Environment and Resources, Fuzhou University, Fujian, 350108, People's Republic of China
| | - Guoxin Sun
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, People's Republic of China
| | - Yanshan Cui
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 101408, People's Republic of China; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, People's Republic of China.
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22
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Roggenbeck BA, Banerjee M, Leslie EM. Cellular arsenic transport pathways in mammals. J Environ Sci (China) 2016; 49:38-58. [PMID: 28007179 DOI: 10.1016/j.jes.2016.10.001] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 10/07/2016] [Accepted: 10/08/2016] [Indexed: 06/06/2023]
Abstract
Natural contamination of drinking water with arsenic results in the exposure of millions of people world-wide to unacceptable levels of this metalloid. This is a serious global health problem because arsenic is a Group 1 (proven) human carcinogen and chronic exposure is known to cause skin, lung, and bladder tumors. Furthermore, arsenic exposure can result in a myriad of other adverse health effects including diseases of the cardiovascular, respiratory, neurological, reproductive, and endocrine systems. In addition to chronic environmental exposure to arsenic, arsenic trioxide is approved for the clinical treatment of acute promyelocytic leukemia, and is in clinical trials for other hematological malignancies as well as solid tumors. Considerable inter-individual variability in susceptibility to arsenic-induced disease and toxicity exists, and the reasons for such differences are incompletely understood. Transport pathways that influence the cellular uptake and export of arsenic contribute to regulating its cellular, tissue, and ultimately body levels. In the current review, membrane proteins (including phosphate transporters, aquaglyceroporin channels, solute carrier proteins, and ATP-binding cassette transporters) shown experimentally to contribute to the passage of inorganic, methylated, and/or glutathionylated arsenic species across cellular membranes are discussed. Furthermore, what is known about arsenic transporters in organs involved in absorption, distribution, and metabolism and how transport pathways contribute to arsenic elimination are described.
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Affiliation(s)
- Barbara A Roggenbeck
- Department of Physiology and Membrane Protein Disease Research Group, University of Alberta, Edmonton, AB, T6G 2H7, Canada.
| | - Mayukh Banerjee
- Department of Physiology and Membrane Protein Disease Research Group, University of Alberta, Edmonton, AB, T6G 2H7, Canada
| | - Elaine M Leslie
- Department of Physiology and Membrane Protein Disease Research Group, University of Alberta, Edmonton, AB, T6G 2H7, Canada; Division of Analytical and Environmental Toxicology, Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, T6G 2G3, Canada.
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23
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Van de Wiele T, Laing GD, Calatayud M. Arsenic from food: biotransformations and risk assessment. Curr Opin Food Sci 2015. [DOI: 10.1016/j.cofs.2015.11.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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