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Wu X, Zou R, Luo G, Wang L, Fang C, Chen S, Li X, Yao H. Simulation and experimental study of gas-phase diffusion coefficient of selenium dioxide. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 947:174499. [PMID: 38971240 DOI: 10.1016/j.scitotenv.2024.174499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2024] [Revised: 06/05/2024] [Accepted: 07/02/2024] [Indexed: 07/08/2024]
Abstract
Improving the removal effect of selenium in wet flue gas desulfurization system is a key way to reduce the emission of selenium pollutants from coal-fired power plants. In order to clarify the removal mechanism of selenium pollutants in the desulfurization tower, it is necessary to obtain accurate selenium gas-phase diffusion coefficient. In this paper, molecular dynamics simulations were used to carry out theoretical calculations of gas-phase diffusion coefficients of SeO2 (the main form of selenium in coal combustion flue gas). The gas-phase diffusion coefficients of SeO2 in the range of 393 K-433 K were measured by a self-developed heavy metal gas diffusion coefficient testing device to verify the accuracy of the molecular dynamics calculations. Furthermore, the calculated gas-phase diffusion coefficients of SeO2 under typical binary and ternary components were obtained by correcting on the basis of Fuller's formula. Finally, a single-droplet absorption model for SeO2 was constructed and experiments were carried out to compare the effect of the gas-phase diffusion coefficient on the accuracy of the model calculations. The error of the model calculations was reduced from 8.09 % to 1.96 % after the correction. In this study, the gas-phase diffusion coefficient of SeO2 in the low-temperature range of coal-fired flue gas was obtained. This study can provide basic data for the development of selenium migration mechanism and control technology.
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Affiliation(s)
- Xiaolong Wu
- State Key Laboratory of Coal Combustion (SKLCC), School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Renjie Zou
- State Key Laboratory of Coal Combustion (SKLCC), School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China.
| | - Guangqian Luo
- State Key Laboratory of Coal Combustion (SKLCC), School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Li Wang
- State Key Laboratory of Coal Combustion (SKLCC), School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Can Fang
- State Key Laboratory of Coal Combustion (SKLCC), School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Sheng Chen
- State Key Laboratory of Coal Combustion (SKLCC), School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Xian Li
- State Key Laboratory of Coal Combustion (SKLCC), School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Hong Yao
- State Key Laboratory of Coal Combustion (SKLCC), School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
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Green D, Bluhm K, Brinkmann M, Raes K, Lane T, Liber K, Janz DM, Hecker M. Cross-species apical microinjected selenomethionine toxicity in embryo-larval fishes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169338. [PMID: 38104801 DOI: 10.1016/j.scitotenv.2023.169338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 12/10/2023] [Accepted: 12/11/2023] [Indexed: 12/19/2023]
Abstract
Selenium (Se) is an essential micronutrient that becomes toxic when exposures minimally exceed those that are physiologically required. Studies on Se contaminated aquatic environments have identified that embryo-larval fishes are at particular risk of Se toxicity, primarily due to maternal Se transfer to developing eggs during oogenesis. This study emulated these exposures in embryo-larval fathead minnow (FHM), rainbow trout (RBT), white sucker (WSu), and white sturgeon (WSt) using embryonic selenomethionine (SeMet) microinjections. Adverse Se-outcomes observed across these species included spinal and edematous deformities, total individuals deformed, and reduced survival. Spinal deformity was the most sensitive sublethal endpoint and developed at the lowest concentrations in WSt (10 % effects concentration (EC10) = 12.42 μg (total) Se/g dry weight (d.w.)) followed by WSu (EC10 = 14.49 μg Se/g d.w.) and FHM (EC10 = 18.10 μg Se/g d.w.). High mortality was observed in RBT, but SeMet influences were confounded by the species' innate sensitivity to the microinjections themselves. 5 % hazardous concentrations derived across exposure type data subsets were ∼49 % higher when derived from within-species maternal transfer exclusive data as opposed to all, or within-species microinjection exclusive, data. These results support the current exclusion of SeMet microinjections during regulatory guideline derivation and their inclusion when studying mechanistic Se toxicity across phylogenetically distant fishes.
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Affiliation(s)
- Derek Green
- Toxicology Graduate Program, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3, Canada; Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3, Canada
| | - Kerstin Bluhm
- Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3, Canada
| | - Markus Brinkmann
- Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3, Canada; School of Environment and Sustainability, University of Saskatchewan, 117 Science Place, Saskatoon, SK S7N 5C8, Canada
| | - Katherine Raes
- Toxicology Graduate Program, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3, Canada; Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3, Canada
| | - Taylor Lane
- Toxicology Graduate Program, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3, Canada; Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3, Canada
| | - Karsten Liber
- Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3, Canada; School of Environment and Sustainability, University of Saskatchewan, 117 Science Place, Saskatoon, SK S7N 5C8, Canada
| | - David M Janz
- Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3, Canada; Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, SK S7N 5B4, Canada
| | - Markus Hecker
- Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3, Canada; School of Environment and Sustainability, University of Saskatchewan, 117 Science Place, Saskatoon, SK S7N 5C8, Canada.
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Burger J, Feigin S, Fojtik A, Dey A, Ng K. Bioaccumulation of Some Metals and Metalloids in Laughing Gulls ( Leucophaeus atricilla): Increases in Mercury and Decreases in Selenium from 2019 to 2022/2023. TOXICS 2023; 11:1007. [PMID: 38133408 PMCID: PMC10748039 DOI: 10.3390/toxics11121007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 12/01/2023] [Accepted: 12/06/2023] [Indexed: 12/23/2023]
Abstract
The elements in blood normally reflect the levels in prey, indicating a recent exposure. Laughing gulls (Leucophaes atricilla) eat mainly horseshoe crab eggs (Limulus polyphemus) in the spring in Delaware Bay, New Jersey. The levels of arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg), and selenium (Se) in the blood of laughing gulls foraging on crab eggs were examined in Delaware Bay to provide information on a species that is normally a generalist, and to determine if the levels of these elements were similar in 2019 and 2022/2023, were intercorrelated, and were related to those in crab eggs. Hg increased from 2019 (136 ± 31 ng/g) to 2022/2023 (473 ± 75 ng/g), while Cd and Se decreased. There were some significant correlations among elements and a close relationship between the element levels in blood and those in crab eggs collected in the same month (except for As). The levels differed between laughing gulls and three species of shorebirds for As and Cd. The elements in the blood of gulls and shorebirds should be similar because they eat mainly the same eggs in the same places. A significant proportion of laughing gull blood samples had levels of Hg and Se that were above the levels associated with adverse effects, which requires further examination.
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Affiliation(s)
- Joanna Burger
- Division of Life Sciences, Rutgers University, 604 Allison Road, Piscataway, NJ 08854, USA;
- Environmental and Occupational Health Sciences Institute (EOHSI), Piscataway, NJ 08854, USA
- Environmental Science Graduate Program, Rutgers University, New Brunswick, NJ 08903, USA;
- Ecology and Evolution Graduate Program, Rutgers University, New Brunswick, NJ 08903, USA
| | - Stephanie Feigin
- Environmental Science Graduate Program, Rutgers University, New Brunswick, NJ 08903, USA;
- Wildlife Restoration Partnerships, 109 Market Lane, Greenwich, NJ 08323, USA
| | - Alinde Fojtik
- Southeastern Cooperative Wildlife Disease Study, University of Georgia, 589 D.W. Brooks Drive, Athens, GA 30677, USA;
| | - Amanda Dey
- 109 Market Lane, Greenwich, NJ 08323, USA;
| | - Kelly Ng
- Division of Life Sciences, Rutgers University, 604 Allison Road, Piscataway, NJ 08854, USA;
- Ecology and Evolution Graduate Program, Rutgers University, New Brunswick, NJ 08903, USA
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Burger J, Feigin S, Ng K, Jeitner C, Tsipoura N, Niles L, Gochfeld M. Some metals and metalloids in the blood of three species of shorebirds increase while foraging during two-week migratory stopover in Delaware Bay, New Jersey. ENVIRONMENTAL RESEARCH 2023; 238:117194. [PMID: 37748669 PMCID: PMC10841762 DOI: 10.1016/j.envres.2023.117194] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 09/22/2023] [Accepted: 09/23/2023] [Indexed: 09/27/2023]
Abstract
Most migratory shorebird species are declining, some are endangered, and some may be vulnerable to contaminants on long distance travel between wintering grounds and high latitude breeding grounds. We examined whether shorebirds accumulated trace elements at the Delaware Bay (New Jersey) stopover by testing the null hypothesis that there was no difference in the levels of arsenic, cadmium, chromium, lead, mercury, and selenium in blood of three species of shorebirds collected early in their stopover compared to levels in blood collected about two weeks later near the end of the stopover, before departing for breeding grounds. There were significantly higher levels of all metals and metalloids in the blood of ruddy turnstone (Arenaria interpres) later in May than earlier. There were seasonal increases in blood levels of arsenic and selenium for all three species. Chromium and lead levels also increased in red knots (Calidris canutus). These increases occurred although the birds were only present for about two weeks. Levels of arsenic, mercury, and lead in knots and selenium in sanderlings (Calidrris alba), exceeded reported effects levels. These results have potential implications for studying the refueling physiology, energetics, and feeding behavior of migratory shorebirds. However, they also suggest cause for concern because the increased contaminant loads occur in a short period, and the high metal level bolus received all in a few days may result in adverse effects.
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Affiliation(s)
- Joanna Burger
- Division of Life Sciences, Rutgers University, 604 Allison Road, Piscataway, NJ, 08854-8082, USA; Environmental and Occupational Health Sciences Institute (EOHSI), Piscataway, New Jersey, 08854, USA; Consortium for Risk Evaluation with Stakeholder Participation, Rutgers University, Piscataway, NJ, 08854, USA; Environmental Science Graduate Program, Rutgers University, New Brunswick, New Jersey, 08903, USA; Ecology and Evolution Graduate Program, Rutgers University, New Brunswick, New Jersey, USA, 08903.
| | - Stephanie Feigin
- Environmental Science Graduate Program, Rutgers University, New Brunswick, New Jersey, 08903, USA; Wildlife Restoration Partnership, 109 Market Land, Greenwich, N 08323, USA.
| | - Kelly Ng
- Division of Life Sciences, Rutgers University, 604 Allison Road, Piscataway, NJ, 08854-8082, USA; Consortium for Risk Evaluation with Stakeholder Participation, Rutgers University, Piscataway, NJ, 08854, USA; Ecology and Evolution Graduate Program, Rutgers University, New Brunswick, New Jersey, USA, 08903.
| | - Christian Jeitner
- Consortium for Risk Evaluation with Stakeholder Participation, Rutgers University, Piscataway, NJ, 08854, USA.
| | - Nellie Tsipoura
- New Jersey Audubon Society, 11 Hardscrabble Rd, Bernardsville, NJ, 07924, USA.
| | - Larry Niles
- Wildlife Restoration Partnership, 109 Market Land, Greenwich, N 08323, USA.
| | - Michael Gochfeld
- Environmental and Occupational Health Sciences Institute (EOHSI), Piscataway, New Jersey, 08854, USA; Consortium for Risk Evaluation with Stakeholder Participation, Rutgers University, Piscataway, NJ, 08854, USA; Environmental and Occupational Health & Justice, Rutgers University School of Public Health, Piscataway, New Jersey, USA, 08854.
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Buchweitz JP, Sheffler R, Puschner B. Common Toxicosis. Vet Clin North Am Food Anim Pract 2023; 39:545-557. [PMID: 37479628 DOI: 10.1016/j.cvfa.2023.06.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/23/2023] Open
Abstract
Veterinarians are often called upon to diagnose health-related issues on the farm that may be related to trace mineral deficiencies or toxicities. Trace mineral feeding rates are often not available due to the proprietary nature of the trace mineral premixes provided by nutritional consultants. The veterinarian needs to be aware of the common clinical signs of trace mineral deficiencies and toxicities, interactions between trace minerals that may result in deficiencies, clinical samples that are necessary for the proper diagnosis, and the recommended normal ranges of each trace mineral depending on the age of the animal.
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Affiliation(s)
- John P Buchweitz
- Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA; MSU Veterinary Diagnostic Laboratory, 4125 Beaumont Road, Lansing, MI 48910, USA.
| | - Rachel Sheffler
- Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA; MSU Veterinary Diagnostic Laboratory, 4125 Beaumont Road, Lansing, MI 48910, USA
| | - Birgit Puschner
- Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA; MSU Veterinary Diagnostic Laboratory, 4125 Beaumont Road, Lansing, MI 48910, USA
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Li X, Liu H, Li D, Lei H, Wei X, Schlenk D, Mu J, Chen H, Yan B, Xie L. Dietary Seleno-l-Methionine Causes Alterations in Neurotransmitters, Ultrastructure of the Brain, and Behaviors in Zebrafish ( Danio rerio). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:11894-11905. [PMID: 34488355 DOI: 10.1021/acs.est.1c03457] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Elevated concentrations of dietary selenium (Se) cause abnormalities and extirpation of fish inhabiting in Se-contaminated environments. However, its effect on fish behavior and the underlying mechanisms remain largely unknown. In this study, two-month-old zebrafish (Danio rerio) was fed seleno-l-methionine (Se-Met) at environmentally relevant concentrations (i.e., control (2.61), low (5.43), medium (12.16), and high (34.61) μg Se/g dry weight (dw), respectively, corresponding to the C, L, M, and H treatments) for 60 days. Targeted metabolomics, histopathological, and targeted transcriptional endpoints were compared to behavioral metrics to evaluate the effects of dietary exposure to Se-Met . The results showed that the levels of total Se and malondialdehyde in fish brains were increased in a dose-dependent pattern. Meanwhile, mitochondrial damages and decreased activities of the mitochondria respiratory chain complexes were observed in the neurons at the M and H treatments. In addition, dietary Se-Met affected neurotransmitters, metabolites, and transcripts of the genes associated with the dopamine, serotonin, gamma-aminobutyric acid, acetylcholine, and histamine signaling pathways in zebrafish brains at the H treatments. The total swimming distance and duration in the Novel Arm were lowered in fish from the H treatment. This study has demonstrated that dietary Se-Met affects the ultrastructure of the zebrafish brain, neurotransmitters, and associated fish behaviors and may help enhance adverse outcome pathways for neurotransmitter-behavior key events in zebrafish.
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Affiliation(s)
- Xiao Li
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
- School of Environment, South China Normal University, University Town, Guangzhou 510006, China
| | - Hongsong Liu
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
- School of Environment, South China Normal University, University Town, Guangzhou 510006, China
| | - Dan Li
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
- School of Environment, South China Normal University, University Town, Guangzhou 510006, China
| | - Haojun Lei
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
- School of Environment, South China Normal University, University Town, Guangzhou 510006, China
| | - Xinrong Wei
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
- School of Environment, South China Normal University, University Town, Guangzhou 510006, China
| | - Daniel Schlenk
- Department of Environmental Sciences, University of California Riverside, Riverside, California 92507, United States
| | - Jingli Mu
- Fujian Key Laboratory of Functional Marine Sensing Materials, Institute of Oceanography, Minjiang University, Fuzhou 350108, China
| | - Hongxing Chen
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
- School of Environment, South China Normal University, University Town, Guangzhou 510006, China
| | - Bo Yan
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
- School of Environment, South China Normal University, University Town, Guangzhou 510006, China
| | - Lingtian Xie
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
- School of Environment, South China Normal University, University Town, Guangzhou 510006, China
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Ohlendorf HM, Santolo GM, Byron ER, Eisert MA. Kesterson Reservoir: 30 Years of Selenium Risk Assessment and Management. INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT 2020; 16:257-268. [PMID: 31646761 DOI: 10.1002/ieam.4222] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 09/23/2019] [Accepted: 10/22/2019] [Indexed: 05/21/2023]
Abstract
Severe effects of selenium (Se) occurred among birds feeding and nesting at Kesterson Reservoir (San Joaquin Valley, California, USA) in 1983 to 1985. This paper describes the integration of site monitoring, risk assessment, and management actions conducted after the effects of Se were discovered. Selenium contamination of the site occurred over just a few years, but actions to resolve the contamination issues required >20 y. The reservoir, a series of 12 ponds totaling about 1280 acres (518 hectares), served for storage and evaporation of subsurface agricultural drainage. Selenium concentrations in reservoir inflow in 1983 were about 300 µg/L, primarily as selenate; within the ponds it was biogeochemically reduced to other inorganic and organic forms and bioaccumulated by biota or deposited to sediments. An estimated 9000 kg of Se were delivered to Kesterson in 1981-1986. A 1985 order required cleanup and abatement of the reservoir, so the United States Bureau of Reclamation and the US Department of the Interior undertook actions and studies to reduce hazards to birds. In 1988, about 1 million cubic yards (764 500 m3 ) of soil were used to fill portions of the reservoir, transforming it into terrestrial habitat. Intensive monitoring began in 1989 to assess the impact of the reservoir on wildlife, provide a basis for adjusting site management, verify the effectiveness of cleanup actions, and provide a basis for modifying future monitoring. Monitoring continued until 2014, with modifications and management actions based on results of 2 risk assessments (1993 and 2000). Monitoring results in 2013-2014 showed that Se concentrations were relatively stable over time and risks to wildlife were low. From the initial problem discovery to the conclusion of actions taken to remediate the site, combining responsive, reactive, and adaptive monitoring; modeling; risk assessment; and mitigation actions proved effective in solving the problem so that risks to wildlife were reduced to minimal levels. Integr Environ Assess Manag 2020;16:257-268. © 2019 SETAC.
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Lane T, Green D, Bluhm K, Raes K, Janz DM, Liber K, Hecker M. In ovo exposure of fathead minnow (Pimephales promelas) to selenomethionine via maternal transfer and embryo microinjection: A comparative study. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2019; 216:105299. [PMID: 31593906 DOI: 10.1016/j.aquatox.2019.105299] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 09/11/2019] [Accepted: 09/12/2019] [Indexed: 06/10/2023]
Abstract
Selenium (Se) is an essential trace element of concern that is known to contaminate aquatic ecosystems as a consequence of releases from anthropogenic activities. Selenium is of particular toxicological concern for egg-laying vertebrates as they bioaccumulate Se through the diet and deposit excess Se to embryo-offspring via maternal transfer, a process which has been shown to result in significant teratogenic effects. The purpose of the present study was to determine and compare the in ovo effects of Se exposure on early development of a laboratory model fish species native to North American freshwater systems, the fathead minnow (Pimephales promelas), through two different exposure routes, maternal transfer and microinjection. For maternal transfer studies, fathead minnow breeding groups (3 females: 2 males) were exposed to diets containing Se-background levels (1.21 μg Se/g food, dry mass [dm]) or environmentally relevant concentrations of selenomethionine (SeMet; 3.88, 8.75 and 26.5 μg Se/g food dm) and bred for 28 days. Embryos were collected at different time points throughout the study to measure Se concentrations and to assess teratogenicity in embryos. While exposure to dietary Se did not negatively affect fecundity among treatment groups, the lowest treatment group (3.88 μg Se/g food dm) produced on average the most embryos per day, per female. The maternal transfer of excess Se occurred rapidly upon onset of exposure, reaching steady-state after approximately 14 days, and embryo Se concentrations increased in a dose-dependent manner. The greatest concentrations of maternally transferred Se significantly increased the total proportion of deformed embryo-larval fathead minnows but did not impact hatchability or survival. In a second study, fathead minnow embryos were injected with SeMet at concentrations of 0.00 (vehicle control), 9.73, 13.5 and 18.9 μg Se/g embryo dm. Microinjection of SeMet did not affect hatchability but significantly increased the proportion of deformed embryo-larval fish in a dose-dependent manner. There was a greater proportion of deformed fathead minnows at embryo Se concentrations of 18.9 μg Se/g embryo dm when exposed via microinjection versus maternal transfer at concentrations of 28.4 μg Se/g embryo dm. However, the findings suggest that both exposure routes induced analogous developmental toxicities in early life stage fish at Se concentrations between 9.73 and 13.5 μg Se/g embryo dm. Overall, this study demonstrated that microinjection has utility for studying the effects of Se in embryo-larval fish and is a promising method for the study of early life stage Se exposure in egg-laying vertebrates.
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Affiliation(s)
- Taylor Lane
- Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5B3, Canada.
| | - Derek Green
- Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5B3, Canada.
| | - Kerstin Bluhm
- School of Environment and Sustainability, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5C8, Canada.
| | - Katherine Raes
- Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5B3, Canada.
| | - David M Janz
- Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5B3, Canada; Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5B4, Canada.
| | - Karsten Liber
- Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5B3, Canada; School of Environment and Sustainability, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5C8, Canada.
| | - Markus Hecker
- Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5B3, Canada; School of Environment and Sustainability, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5C8, Canada.
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Layered Double Hydroxide Sorbents for Removal of Selenium from Power Plant Wastewaters. CHEMENGINEERING 2019. [DOI: 10.3390/chemengineering3010020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Selenium is an essential trace element but is increasingly becoming a contaminant of concern in the electric power industry due to the challenges of removing solubilized selenate anions, particularly in the presence of sulfate. In this work, we evaluate granulated layered double hydroxide (LDH) materials as sorbents for selenium removal from wastewaters obtained from a natural gas power plant with the aim to elucidate the effect of competing ions on the sorption capacities for selenium removal. We first present jar test data, followed by small-scale column testing in 0.43 inch (1.1 cm) and 2 inch (5.08 cm) diameter testbed columns for the treatment of as-obtained cooling tower blowdown waters and plant wastewaters. Finally, we present field results from a pilot-scale study evaluating the LDH media for treatment of cooling tower blowdown water. We find that despite the high levels of total dissolved solids and competing sulfate ions, the selenium oxoanions and other regulated metals such as chromium and arsenic are successfully removed using LDH media without needing any pre-treatment or pH adjustment of the wastewater.
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Preparation and purification of organic samples for selenium isotope studies. PLoS One 2018; 13:e0193826. [PMID: 29509798 PMCID: PMC5839574 DOI: 10.1371/journal.pone.0193826] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Accepted: 02/20/2018] [Indexed: 11/25/2022] Open
Abstract
Selenium (Se) is an important micronutrient but also a strong toxin with a narrow tolerance range for many organisms. As such, a globally heterogeneous Se distribution in soils is responsible for various disease patterns (i.e. Se excess and deficiency) and environmental problems, whereby plants play a key role for the Se entrance into the biosphere. Selenium isotope variations were proved to be a powerful tracer for redox processes and are therefore promising for the exploration of the species dependent Se metabolism in plants and the Se cycling within the Critical Zone. Plant cultivation setups enable systematic controlled investigations, but samples derived from them–plant tissue and phytoagar–are particularly challenging and require specific preparation and purification steps to ensure precise and valid Se isotope analytics performed with HG-MC-ICP-MS. In this study, different methods for the entire process from solid tissue preparation to Se isotope measurements were tested, optimized and validated. A particular microwave digestion procedure for plant tissue and a vacuum filtration method for phytoagar led to full Se recoveries, whereby unfavorable organic residues were reduced to a minimum. Three purification methods predominantly described in the literature were systematically tested with pure Se solution, high concentrated multi-element standard solution as well as plant and phytoagar as target matrices. All these methods efficiently remove critical matrix elements, but differ in Se recovery and organic residues. Validation tests doping Se-free plant material and phytoagar with a reference material of known Se isotope composition revealed the high impact of organic residues on the accuracy of MC-ICP-MS measurements. Only the purification method with no detectable organic residues, hydride generation and trapping, results in valid mass bias correction for plant samples with an average deviation to true δ82/76Se values of 0.2 ‰ and a reproducibility (2 SD) of ± 0.2 ‰. For phytoagar this test yields a higher deviation of 1.1 ‰ from the true value and a 2 SD of ± 0.1 ‰. The application of the developed methods to cultivated plants shows sufficient accuracy and precision and is a promising approach to resolve plant internal Se isotope fractionations, for which respective δ82/76Se values of +2.3 to +3.5 ‰ for selenate and +1.2 to +1.9 ‰ for selenite were obtained.
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De La Riva DG, Hladun KR, Vindiola BG, Trumble JT. Arthropod communities in a selenium-contaminated habitat with a focus on ant species. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2017; 220:234-241. [PMID: 27692883 DOI: 10.1016/j.envpol.2016.09.052] [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: 06/21/2016] [Revised: 09/09/2016] [Accepted: 09/15/2016] [Indexed: 06/06/2023]
Abstract
The selenium contamination event that occurred at Kesterson Reservoir (Merced Co., CA) during the 1970-80s is a frequently cited example for the negative effects of contamination on wildlife. Despite the importance of arthropods for ecosystem services and functioning, relatively little information is available as to the impacts of pollution on arthropod community dynamics. We conducted surveys of the arthropod community present at Kesterson Reservoir to assess the impacts of selenium contamination on arthropod diversity, with a focus on ant species richness, composition and density. Trophic groups were compared to determine which arthropods were potentially receiving the greatest selenium exposure. Plant samples were analyzed to determine the selenium content by site and by location within plant. Soil concentrations varied across the study sites, but not across habitat types. Topsoil contained higher levels of selenium compared to core samples. Plants contained similar concentrations of selenium in their leaves, stems and flowers, but flowers contained the greatest range of concentrations. Individuals within the detritivores/decomposers and predators accumulated the greatest concentrations of selenium, whereas nectarivores contained the lowest concentrations. Species composition differed across the sites: Dorymyrmex bicolor was located only at the site containing the greatest soil selenium concentration, but Solenopsis xyloni was found at most sites and was predominant at six of the sites. Selenium concentrations in ants varied by species and collection sites. Nest density was also found to differ across sites, but was not related to soil selenium or any of the habitat variables measured in our study. Selenium was not found to impact species richness, but was a significant variable for the occurrence of two out of the eight native species identified.
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Affiliation(s)
- Deborah G De La Riva
- Department of Entomology, University of California, Riverside, 900 University Ave., Riverside, CA, 92521, USA.
| | - Kristen R Hladun
- Department of Entomology, University of California, Riverside, 900 University Ave., Riverside, CA, 92521, USA
| | - Beatriz G Vindiola
- Department of Environmental Sciences, University of California, Riverside, 900 University Ave., Riverside, CA, 92521, USA
| | - John T Trumble
- Department of Entomology, University of California, Riverside, 900 University Ave., Riverside, CA, 92521, USA
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Xie L, Wu X, Chen H, Dong W, Cazan AM, Klerks PL. A low level of dietary selenium has both beneficial and toxic effects and is protective against Cd-toxicity in the least killifish Heterandria formosa. CHEMOSPHERE 2016; 161:358-364. [PMID: 27448316 DOI: 10.1016/j.chemosphere.2016.07.035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 07/02/2016] [Accepted: 07/11/2016] [Indexed: 06/06/2023]
Abstract
As an essential element, selenium (Se) is beneficial at low levels yet toxic at high levels. The present study assessed the effects of dietary exposure to Se in the least killifish Heterandria formosa, and investigated how this exposure influences the effects of a subsequent exposure to cadmium (Cd). The fish were pre-exposed to an environmentally relevant concentration (2 μg g(-1) dry wt) of dietary selenite (Se(4+)) or seleno-l-methionine (Se-Met) for 10 d. The same fish were then exposed to 0.5 mg L(-1) of Cd for 5 d. Both Se(IV) and Se-Met rapidly accumulated in H. formosa. Results for the two Se species were generally similar in this study. Fish exposed to Se had lower levels of lipid peroxidation (measured as levels of thiobarbituric acid reactive substances or TBARS) and a higher catalase (CAT) activity. In contrast, their Na(+)/K(+)-ATPase activity was reduced. The Cd exposure resulted in an increase in lipid peroxidation and decreases in the activities of catalase and Na(+)/K(+)-ATPase. The Cd-exposed H. formosa that were pre-exposed to Se had lower Cd body burdens, less lipid peroxidation, and higher catalase activity, than did fish not pre-exposed to Se. The Se exposure did not have a protective effect on the Cd-induced reduction in Na(+)/K(+)-ATPase activity. These results clearly demonstrate that a Se-enriched diet reduces some (but not all) forms of Cd-toxicity and that Se can simultaneously have beneficial and detrimental effects, making it difficult to predict the net outcome of changes in dietary Se levels for fish.
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Affiliation(s)
- Lingtian Xie
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Liaoning 110016, PR China.
| | - Xing Wu
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Liaoning 110016, PR China
| | - Hongxing Chen
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Liaoning 110016, PR China
| | - Wu Dong
- Inner Mongolia University for the Nationalities, Tongliao 028000, PR China.
| | - Alfy Morales Cazan
- Department of Biology, University of Louisiana at Lafayette, P. O. Box 43602, Lafayette, LA 70504-3602, USA
| | - Paul L Klerks
- Department of Biology, University of Louisiana at Lafayette, P. O. Box 43602, Lafayette, LA 70504-3602, USA
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Xie L, Wu X, Chen H, Luo Y, Guo Z, Mu J, Blankson ER, Dong W, Klerks PL. The bioaccumulation and effects of selenium in the oligochaete Lumbriculus variegatus via dissolved and dietary exposure routes. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2016; 178:1-7. [PMID: 27450235 DOI: 10.1016/j.aquatox.2016.07.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 07/13/2016] [Accepted: 07/15/2016] [Indexed: 06/06/2023]
Abstract
Aquatic organisms take up selenium from solution and from their diets. Many questions remain regarding the relative importance of selenium accumulation from these sources and resulting effects in benthic invertebrates. The present study addressed the toxicity and accumulation of Se via dissolved and dietary exposures to three different Se species, in the freshwater oligochaete Lumbriculus variegatus. Worms were exposed to 20μg/g dry weight of selenite (Se(IV)), selenate (Se(VI)), or seleno-l-methionine (Se-Met) in their diet (sediment) or to 15μg/L dissolved Se in water-only exposures. While the dissolved and sediment Se levels differed greatly, such levels may co-occur at a Se-contaminated site. Se accumulation, worm population growth, lipid peroxidation (as TBARS), and Na(+)/K(+)-ATPase activity were quantified at the end of the 2-week exposure. The sediment Se-Met exposure caused 100% mortality, while worm densities were reduced by the other exposures except the Se(VI) one. Se bioaccumulation was generally higher for the sediment-Se exposure than the dissolved-Se ones, and was higher for Se(IV) than Se(VI) in the dissolved-Se exposure but not the sediment-Se one. The Se accumulation was highest for Se-Met. The oligochaetes that accumulated Se had higher levels of lipid peroxidation and reduced Na(+)/K(+)-ATPase activity. The present study's findings of differences in Se accumulation and toxicity for the three Se species, with effects generally but not exclusively a function of Se body burdens, underscore the need for research on these issues in invertebrates. Moreover, the results imply that the dietary uptake route is the predominant one for Se accumulation in L. variegatus.
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Affiliation(s)
- Lingtian Xie
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Liaoning 110016, PR China.
| | - Xing Wu
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Liaoning 110016, PR China
| | - Hongxing Chen
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Liaoning 110016, PR China
| | - Yongju Luo
- Guangxi Academy of Fishery Science, Guangxi 530021, PR China.
| | - Zhongbao Guo
- Guangxi Academy of Fishery Science, Guangxi 530021, PR China
| | - Jingli Mu
- Division of Marine Chemistry, National Marine Environmental Monitoring Center, Dalian, Liaoning 116023, PR China
| | - Emmanuel R Blankson
- Department of Biology, University of Louisiana at Lafayette, P. O. Box 43602, Lafayette, LA 70504-3602, USA
| | - Wu Dong
- Inner Mongolia University for the Nationalities, Tongliao 028000, PR China
| | - Paul L Klerks
- Department of Biology, University of Louisiana at Lafayette, P. O. Box 43602, Lafayette, LA 70504-3602, USA
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Tan LC, Nancharaiah YV, van Hullebusch ED, Lens PNL. Selenium: environmental significance, pollution, and biological treatment technologies. Biotechnol Adv 2016; 34:886-907. [PMID: 27235190 DOI: 10.1016/j.biotechadv.2016.05.005] [Citation(s) in RCA: 220] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Revised: 04/26/2016] [Accepted: 05/21/2016] [Indexed: 10/21/2022]
Abstract
Selenium is an essential trace element needed for all living organisms. Despite its essentiality, selenium is a potential toxic element to natural ecosystems due to its bioaccumulation potential. Though selenium is found naturally in the earth's crust, especially in carbonate rocks and volcanic and sedimentary soils, about 40% of the selenium emissions to atmospheric and aquatic environments are caused by various industrial activities such as mining-related operations. In recent years, advances in water quality and pollution monitoring have shown that selenium is a contaminant of potential environmental concern. This has practical implications on industry to achieve the stringent selenium regulatory discharge limit of 5μgSeL(-1) for selenium containing wastewaters set by the United States Environmental Protection Agency. Over the last few decades, various technologies have been developed for the treatment of selenium-containing wastewaters. Biological selenium reduction has emerged as the leading technology for removing selenium from wastewaters since it offers a cheaper alternative compared to physico-chemical treatments and is suitable for treating dilute and variable selenium-laden wastewaters. Moreover, biological treatment has the advantage of forming elemental selenium nanospheres which exhibit unique optical and spectral properties for various industrial applications, i.e. medical, electrical, and manufacturing processes. However, despite the advances in biotechnology employing selenium reduction, there are still several challenges, particularly in achieving stringent discharge limits, the long-term stability of biogenic selenium and predicting the fate of bioreduced selenium in the environment. This review highlights the significance of selenium in the environment, health, and industry and biotechnological advances made in the treatment of selenium contaminated wastewaters. The challenges and future perspectives are overviewed considering recent biotechnological advances in the management of these selenium-laden wastewaters.
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Affiliation(s)
- Lea Chua Tan
- UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands.
| | - Yarlagadda V Nancharaiah
- Biofouling and Biofilm Process Section, Water and Steam Chemistry Division, Bhabha Atomic Research Centre Kalpakkam, 603102 Tamil Nadu, India.
| | - Eric D van Hullebusch
- Université Paris-Est, Laboratoire Géomatériaux et Environnement (EA 4508), UPEM, 77454 Marne-la-Vallée, France.
| | - Piet N L Lens
- UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands; Department of Chemistry and Bioengineering, Tampere University of Technology, P.O-Box 541, Tampere, Finland.
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Santos S, Ungureanu G, Boaventura R, Botelho C. Selenium contaminated waters: An overview of analytical methods, treatment options and recent advances in sorption methods. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 521-522:246-60. [PMID: 25847169 DOI: 10.1016/j.scitotenv.2015.03.107] [Citation(s) in RCA: 144] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 03/23/2015] [Accepted: 03/23/2015] [Indexed: 05/17/2023]
Abstract
Selenium is an essential trace element for many organisms, including humans, but it is bioaccumulative and toxic at higher than homeostatic levels. Both selenium deficiency and toxicity are problems around the world. Mines, coal-fired power plants, oil refineries and agriculture are important examples of anthropogenic sources, generating contaminated waters and wastewaters. For reasons of human health and ecotoxicity, selenium concentration has to be controlled in drinking-water and in wastewater, as it is a potential pollutant of water bodies. This review article provides firstly a general overview about selenium distribution, sources, chemistry, toxicity and environmental impact. Analytical techniques used for Se determination and speciation and water and wastewater treatment options are reviewed. In particular, published works on adsorption as a treatment method for Se removal from aqueous solutions are critically analyzed. Recent published literature has given particular attention to the development and search for effective adsorbents, including low-cost alternative materials. Published works mostly consist in exploratory findings and laboratory-scale experiments. Binary metal oxides and LDHs (layered double hydroxides) have presented excellent adsorption capacities for selenium species. Unconventional sorbents (algae, agricultural wastes and other biomaterials), in raw or modified forms, have also led to very interesting results with the advantage of their availability and low-cost. Some directions to be considered in future works are also suggested.
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Affiliation(s)
- Sílvia Santos
- LSRE - Laboratory of Separation and Reaction Engineering, Associate Laboratory LSRE/LCM, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
| | - Gabriela Ungureanu
- LSRE - Laboratory of Separation and Reaction Engineering, Associate Laboratory LSRE/LCM, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Rui Boaventura
- LSRE - Laboratory of Separation and Reaction Engineering, Associate Laboratory LSRE/LCM, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Cidália Botelho
- LSRE - Laboratory of Separation and Reaction Engineering, Associate Laboratory LSRE/LCM, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
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Winkel LHE, Vriens B, Jones GD, Schneider LS, Pilon-Smits E, Bañuelos GS. Selenium cycling across soil-plant-atmosphere interfaces: a critical review. Nutrients 2015; 7:4199-239. [PMID: 26035246 PMCID: PMC4488781 DOI: 10.3390/nu7064199] [Citation(s) in RCA: 186] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 05/18/2015] [Indexed: 12/16/2022] Open
Abstract
Selenium (Se) is an essential element for humans and animals, which occurs ubiquitously in the environment. It is present in trace amounts in both organic and inorganic forms in marine and freshwater systems, soils, biomass and in the atmosphere. Low Se levels in certain terrestrial environments have resulted in Se deficiency in humans, while elevated Se levels in waters and soils can be toxic and result in the death of aquatic wildlife and other animals. Human dietary Se intake is largely governed by Se concentrations in plants, which are controlled by root uptake of Se as a function of soil Se concentrations, speciation and bioavailability. In addition, plants and microorganisms can biomethylate Se, which can result in a loss of Se to the atmosphere. The mobilization of Se across soil-plant-atmosphere interfaces is thus of crucial importance for human Se status. This review gives an overview of current knowledge on Se cycling with a specific focus on soil-plant-atmosphere interfaces. Sources, speciation and mobility of Se in soils and plants will be discussed as well as Se hyperaccumulation by plants, biofortification and biomethylation. Future research on Se cycling in the environment is essential to minimize the adverse health effects associated with unsafe environmental Se levels.
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Affiliation(s)
- Lenny H E Winkel
- Swiss Federal Institute of Technology (ETH), Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, CH-8092 Zurich, Switzerland.
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse 133, P.O. Box 611, CH-8600 Duebendorf, Switzerland.
| | - Bas Vriens
- Swiss Federal Institute of Technology (ETH), Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, CH-8092 Zurich, Switzerland.
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse 133, P.O. Box 611, CH-8600 Duebendorf, Switzerland.
| | - Gerrad D Jones
- Eawag: Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse 133, P.O. Box 611, CH-8600 Duebendorf, Switzerland.
| | - Leila S Schneider
- Swiss Federal Institute of Technology (ETH), Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, CH-8092 Zurich, Switzerland.
| | | | - Gary S Bañuelos
- USDA, Agricultural Research Service, San Joaquin Valley Agricultural Center, 9611 South Riverbend Avenue, Parlier, CA 93648, USA.
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Bañuelos GS, Arroyo I, Pickering IJ, Yang SI, Freeman JL. Selenium biofortification of broccoli and carrots grown in soil amended with Se-enriched hyperaccumulator Stanleya pinnata. Food Chem 2014; 166:603-608. [PMID: 25053099 DOI: 10.1016/j.foodchem.2014.06.071] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 05/06/2014] [Accepted: 06/16/2014] [Indexed: 11/29/2022]
Abstract
Amending soils with Se-hyperaccumulator plant derived sources of selenium (Se) may be useful for increasing the Se content in food crops in Se-deficient regions of the world. In this study we evaluated total Se and the different chemical species of Se in broccoli and carrots grown in soils amended with ground shoots of the Se-hyperaccumulator Stanleyapinnata. With increasing application rates of S. pinnata, total plant Se concentrations increased to nutritionally ideal levels inside edible parts. Selenium compounds in aqueous extracts were analyzed by SAX-HPLC-ICPMS and identified as a variety of mainly organic-Se forms. Together with bulk Se K-edge X-ray absorption near-edge structure (XANES) analysis performed on broccoli florets, carrot roots and shoots, dried ground S. pinnata, and the amended soil at post-plant, we demonstrate that Se-enriched S. pinnata is valuable as a soil amendment for enriching broccoli and carrots with healthful forms of organic-Se.
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Affiliation(s)
- Gary S Bañuelos
- USDA, Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648-9757, USA.
| | - Irvin Arroyo
- USDA, Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA 93648-9757, USA
| | - Ingrid J Pickering
- Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada
| | - Soo In Yang
- Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada
| | - John L Freeman
- Department of Biology, California State University Fresno, Fresno, CA 93740, USA; Intrinsyx Technologies Corporation, Space Bio-Sciences Division, NASA-Ames Research Center, Moffett Field, CA 94035, USA.
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Lai CY, Yang X, Tang Y, Rittmann BE, Zhao HP. Nitrate shaped the selenate-reducing microbial community in a hydrogen-based biofilm reactor. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:3395-3402. [PMID: 24579788 DOI: 10.1021/es4053939] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
To study the effect of nitrate (NO3(-)) on selenate (SeO4(2-)) reduction, we tested a H2-based biofilm with a range of influent NO3(-) loadings. When SeO4(2-) was the only electron acceptor (stage 1), 40% of the influent SeO4(2-) was reduced to insoluble elemental selenium (Se(0)). SeO4(2-) reduction was dramatically inhibited when NO3(-) was added at a surface loading larger than 1.14 g of N m(-2) day(-1), when H2 delivery became limiting and only 80% of the input NO3(-) was reduced (stage 2). In stage 3, when NO3(-) was again removed from the influent, SeO4(2-) reduction was re-established and increased to 60% conversion to Se(0). SeO4(2-) reduction remained stable at 60% in stages 4 and 5, when the NO3(-) surface loading was re-introduced at ≤ 0.53 g of N m(-2) day(-1), allowing for complete NO3(-) reduction. The selenate-reducing microbial community was significantly reshaped by the high NO3(-) surface loading in stage 2, and it remained stable through stages 3-5. In particular, the abundance of α-Proteobacteria decreased from 30% in stage 1 to less than 10% of total bacteria in stage 2. β-Proteobacteria, which represented about 55% of total bacteria in the biofilm in stage 1, increased to more than 90% of phylotypes in stage 2. Hydrogenophaga, an autotrophic denitrifier, was positively correlated with NO3(-) flux. Thus, introducing a NO3(-) loading high enough to cause H2 limitation and suppress SeO4(2-) reduction had a long-lasting effect on the microbial community structure, which was confirmed by principal coordinate analysis, although SeO4(2-) reduction remained intact.
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Affiliation(s)
- Chun-Yu Lai
- Ministry of Education, Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University , Hangzhou 310029, People's Republic of China
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20
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Schmidt R, Tantoyotai P, Fakra SC, Marcus MA, Yang SI, Pickering IJ, Bañuelos GS, Hristova KR, Freeman JL. Selenium biotransformations in an engineered aquatic ecosystem for bioremediation of agricultural wastewater via brine shrimp production. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:5057-5065. [PMID: 23621086 DOI: 10.1021/es305001n] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
An engineered aquatic ecosystem was specifically designed to bioremediate selenium (Se), occurring as oxidized inorganic selenate from hypersalinized agricultural drainage water while producing brine shrimp enriched in organic Se and omega-3 and omega-6 fatty acids for use in value added nutraceutical food supplements. Selenate was successfully bioremediated by microalgal metabolism into organic Se (seleno-amino acids) and partially removed via gaseous volatile Se formation. Furthermore, filter-feeding brine shrimp that accumulated this organic Se were removed by net harvest. Thriving in this engineered pond system, brine shrimp ( Artemia franciscana Kellogg) and brine fly (Ephydridae sp.) have major ecological relevance as important food sources for large populations of waterfowl, breeding, and migratory shore birds. This aquatic ecosystem was an ideal model for study because it mimics trophic interactions in a Se polluted wetland. Inorganic selenate in drainage water was metabolized differently in microalgae, bacteria, and diatoms where it was accumulated and reduced into various inorganic forms (selenite, selenide, or elemental Se) or partially incorporated into organic Se mainly as selenomethionine. Brine shrimp and brine fly larva then bioaccumulated Se from ingesting aquatic microorganisms and further metabolized Se predominately into organic Se forms. Importantly, adult brine flies, which hatched from aquatic larva, bioaccumulated the highest Se concentrations of all organisms tested.
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Affiliation(s)
- Radomir Schmidt
- Department of Land, Air and Water Resources, University of California, Davis, California 95616, United States
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21
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Lockard L, Rowe CL, Heyes A. Dietary selenomethionine exposure induces physical malformations and decreases growth and survival to metamorphosis in an amphibian (Hyla chrysoscelis). ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2013; 64:504-513. [PMID: 23229196 DOI: 10.1007/s00244-012-9850-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Accepted: 11/14/2012] [Indexed: 06/01/2023]
Abstract
Selenium (Se) is an essential micronutrient with a narrow therapeutic concentration range. The relative toxicity of Se increases as it is biotransformed into organic compounds, primarily selenomethionine (SeMet), within the aquatic food chain. Effects of aquatic Se contamination are well quantified for many freshwater fish and aquatic bird species, but impacts on amphibians are not well known. This study investigated the responses of larval Cope's gray tree frogs (Hyla chrysoscelis) fed a diet enriched with one of two concentrations of SeMet (50.1 and 489.9 μg Se g(-1) dw [low and high groups, respectively]) by way of a food-limited (ration) or ad libitum (ad lib) feeding regimen. The high dose caused 100 % mortality during the larval period independent of resource provision levels. Regardless of feeding regimen, the low dose decreased larval survival and successful metamorphosis relative to control treatments. The low dose also induced rear limb deformities in ≤73 % of individuals initiating metamorphosis. Providing low-dose food by way of a rationed feeding regimen decreased observed toxicity, likely because of decreased dietary exposure to SeMet relative to the low ad lib treatment. Individuals from the low ration treatment had decreased wet mass at initiation and completion of metamorphic climax (Gosner stages 42 through 46) compared with those from the control ad lib treatment, indicating that resource limitation combined with Se exposure might negatively affect energy stores after metamorphosis. However, lipid content analyses of recently metamorphosed individuals did not reveal any influence of treatment or resource provision on energy stored as lipids. The mean tissue Se concentration of individuals that received the low dose and completed metamorphosis was significantly greater than that of control ad lib or ration individuals at the same developmental stage. This study demonstrates that larval exposure to dietary SeMet can decrease growth and survival and induce deformities in a developing amphibian. Furthermore, retention of Se body burdens through metamorphosis suggests that surviving individuals can transport Se accumulated from contaminated aquatic environments into terrestrial food webs.
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Affiliation(s)
- Laura Lockard
- Chesapeake Biological Laboratory, University of Maryland Center for Environmental Science, P.O. Box 38, Solomons, MD 20688, USA
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22
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Benko I, Nagy G, Tanczos B, Ungvari E, Sztrik A, Eszenyi P, Prokisch J, Banfalvi G. Subacute toxicity of nano-selenium compared to other selenium species in mice. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2012; 31:2812-20. [PMID: 22927138 DOI: 10.1002/etc.1995] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 07/25/2012] [Accepted: 08/02/2012] [Indexed: 05/20/2023]
Abstract
Sixteen groups of mice were fed diets containing different selenium species to compare their toxicity. Inorganic sodium selenate and sodium hydroselenite, elementary nanoSe, organic Sel-Plex, and Lacto-MicroSelenium were administered for 14 d at concentrations of 0.5, 5, and 50 ppm Se, equivalent to 0.5, 5, and 50 mg Se/kg food, corresponding to an estimated 4, 40, and 400 µg/kg body weight/d Se uptake, respectively. At the end of the treatment, body, liver, spleen, kidney, heart, and brain weights were measured, mice were subjected to necropsy, and histological examinations were performed on the liver. At lower Se doses (0.5 and 5 ppm) a moderate reduction was observed in the number of bone marrow and white blood cells and in granulocyte-macrophage colony-forming units (GM-CFUs) relative to the untreated control group of mice. A comparison of lowest toxic doses of sodium selenite in mice (0.5 ppm) and mallard (10 ppm) indicates that birds are more resistant to Se than rodents. In mice, a small but measurable weight loss was observed after 5 ppm selenate and LactoMicroSe treatment. The most significant changes took place after 50-ppm administration in body and spleen weight, hematology, and liver histology. Toxicity was more pronounced when inorganic Se was applied than after subacute application of Sel-Plex, nanoSe, or LactoMicroSe. To summarize the effects, the authors' 14-d murine subacute toxicity study showed that the toxicity of Se species decreased in the following order: selenate > selenite > nanoSe > Sel-Plex > LactoMicroSe.
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Affiliation(s)
- Ilona Benko
- Department of Pharmacology and Pharmacotherapy, University of Debrecen, Debrecen, Hungary
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23
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Heinz GH, Hoffman DJ, Klimstra JD, Stebbins KR. A comparison of the teratogenicity of methylmercury and selenomethionine injected into bird eggs. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2012; 62:519-28. [PMID: 22042039 DOI: 10.1007/s00244-011-9717-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Accepted: 09/26/2011] [Indexed: 05/22/2023]
Abstract
Methylmercury chloride and seleno-L-methionine were injected separately or in combinations into the fertile eggs of mallards (Anas platyrhynchos), chickens (Gallus gallus), and double-crested cormorants (Phalacrocorax auritus), and the incidence and types of teratogenic effects were recorded. For all three species, selenomethionine alone caused more deformities than did methylmercury alone. When mallard eggs were injected with the lowest dose of selenium (Se) alone (0.1 μg/g), 28 of 44 embryos and hatchlings were deformed, whereas when eggs were injected with the lowest dose of mercury (Hg) alone (0.2 μg/g), only 1 of 56 embryos or hatchlings was deformed. Mallard embryos seemed to be more sensitive to the teratogenic effects of Se than chicken embryos: 0 of 15 chicken embryos or hatchlings from eggs injected with 0.1 μg/g Se exhibited deformities. Sample sizes were small with double-crested cormorant eggs, but they also seemed to be less sensitive to the teratogenic effects of Se than mallard eggs. There were no obvious differences among species regarding Hg-induced deformities. Overall, few interactions were apparent between methylmercury and selenomethionine with respect to the types of deformities observed. However, the deformities spina bifida and craniorachischisis were observed only when Hg and Se were injected in combination. One paradoxical finding was that some doses of methylmercury seemed to counteract the negative effect selenomethionine had on hatching of eggs while at the same time enhancing the negative effect selenomethionine had on creating deformities. When either methylmercury or selenomethionine is injected into avian eggs, deformities start to occur at much lower concentrations than when the Hg or Se is deposited naturally in the egg by the mother.
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Affiliation(s)
- Gary H Heinz
- Patuxent Wildlife Research Center, United States Geological Survey, BARC-East, Building 308, 10300 Baltimore Avenue, Beltsville, MD 20705, USA.
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Freeman JL, Bañuelos GS. Selection of salt and boron tolerant selenium hyperaccumulator Stanleya pinnata genotypes and characterization of Se phytoremediation from agricultural drainage sediments. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:9703-10. [PMID: 21988205 DOI: 10.1021/es201600f] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Genetic variation in salt (Na(2)SO(4), NaCl) and boron (B) tolerance among four ecotypes of the selenium (Se) hyperaccumulator Stanleya pinnata (Pursh) Britton was utilized to select tolerant genotypes capable of phytoremediating Se from salt, B, and Se-laden agricultural drainage sediment. The few individual salt/B tolerant genotypes were successfully selected from among a large population of highly salt/B sensitive seedlings. The distribution, hyperaccumulation, and volatilization of Se were then examined in selected plants capable of tolerating the high salt/B laden drainage sediment. Salt/B tolerant genotypes from each of the four ecotypes had mean Se concentrations ranging from 2510 ± 410 to 1740 ± 620 in leaves and 3180 ± 460 to 2500 ± 1060 in seeds (μg Se g(-1) DW ± SD), while average daily Se volatilization rates ranged from 722 ± 375 to 1182 ± 575 (μg Se m(-2) d(-1) ± SD). After two growing seasons (∼18 months), we estimated that hyperaccumulation and volatilization of Se by tolerant S. pinnata genotypes and their associated microbes can remove approximately 30% of the total soil Se in 0-30 cm sediment. The salt/B tolerant S. pinnata genotypes selected and characterized herein represent promising new tools for the successful phytoremediation of Se from salt/B and Se-laden agricultural drainage sediments.
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Affiliation(s)
- John L Freeman
- Agricultural Research Service, US Department of Agriculture, Parlier, California 93648, United States
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Glibert PM, Fullerton D, Burkholder JM, Cornwell JC, Kana TM. Ecological Stoichiometry, Biogeochemical Cycling, Invasive Species, and Aquatic Food Webs: San Francisco Estuary and Comparative Systems. ACTA ACUST UNITED AC 2011. [DOI: 10.1080/10641262.2011.611916] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Glibert PM. Long-Term Changes in Nutrient Loading and Stoichiometry and Their Relationships with Changes in the Food Web and Dominant Pelagic Fish Species in the San Francisco Estuary, California. ACTA ACUST UNITED AC 2010. [DOI: 10.1080/10641262.2010.492059] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Lenz M, Lens PNL. The essential toxin: the changing perception of selenium in environmental sciences. THE SCIENCE OF THE TOTAL ENVIRONMENT 2009; 407:3620-33. [PMID: 18817944 DOI: 10.1016/j.scitotenv.2008.07.056] [Citation(s) in RCA: 200] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2008] [Revised: 07/17/2008] [Accepted: 07/30/2008] [Indexed: 05/12/2023]
Abstract
During the last decades, the perception of selenium has undergone substantial changes. While its toxic effects were recognized causing hair and hoof loss in animals during the 1930s, its essential role in microbial, animal and human metabolism has been recognized later, i.e. with the discovery of selenium deficiency causing "white muscle disease" in feedstock in the 1950s. Nowadays, the positive effect of systematic selenium supplementation is discussed in manifold topics such as cancer or diabetes prevention and avian influenza susceptibility. Treatment of selenium containing waste streams poses a notable challenge to environmental engineers, and to date no ultimate solution has been found for e.g. the selenium contamination in agricultural areas of the western USA. For the future, selenium contamination carries an imminent danger, if the increasing energy demand is covered by fossil fuel combustion, which will lead to major selenium emission and toxicity. This review presents current knowledge of selenium's role in environmental sciences and outlines potentially feasible treatment options targeting a variety of selenium contaminated waste streams.
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Affiliation(s)
- Markus Lenz
- Sub-Department of Environmental Technology, Wageningen University, Bomenweg 2, 6700 EV Wageningen, The Netherlands
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Diaz X, Johnson WP, Naftz DL. Selenium mass balance in the Great Salt Lake, Utah. THE SCIENCE OF THE TOTAL ENVIRONMENT 2009; 407:2333-2341. [PMID: 19144389 DOI: 10.1016/j.scitotenv.2008.11.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2008] [Revised: 11/12/2008] [Accepted: 11/13/2008] [Indexed: 05/27/2023]
Abstract
A mass balance for Se in the south arm of the Great Salt Lake was developed for September 2006 to August 2007 of monitoring for Se loads and removal flows. The combined removal flows (sedimentation and volatilization) totaled to a geometric mean value of 2079 kg Se/yr, with the estimated low value being 1255 kg Se/yr, and an estimated high value of 3143 kg Se/yr at the 68% confidence level. The total (particulates+dissolved) loads (via runoff) were about 1560 kg Se/yr, for which the error is expected to be +/-15% for the measured loads. Comparison of volatilization to sedimentation flux demonstrates that volatilization rather than sedimentation is likely the major mechanism of selenium removal from the Great Salt Lake. The measured loss flows balance (within the range of uncertainties), and possibly surpass, the measured annual loads. Concentration histories were modeled using a simple mass balance, which indicated that no significant change in Se concentration was expected during the period of study. Surprisingly, the measured total Se concentration increased during the period of the study, indicating that the removal processes operate at their low estimated rates, and/or there are unmeasured selenium loads entering the lake. The selenium concentration trajectories were compared to those of other trace metals to assess the significance of selenium concentration trends.
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Affiliation(s)
- Ximena Diaz
- Department of Geology and Geophysics, University of Utah, 135 S 1460 E Salt Lake City, UT 84112, United States
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Hazelton SG, Pierce DT. Ultratrace Determination of Inorganic Selenium without Signal Calibration. Anal Chem 2007; 79:4558-63. [PMID: 17508714 DOI: 10.1021/ac061838t] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To more readily evaluate the complex biogeochemistry of selenium, a flow-through electrochemical method was developed that can accurately determine Se(IV) concentrations in aqueous samples to part-per-trillion levels without signal calibration. Stripping methods were used in conjunction with a high-efficiency, flow-through cell. The cell was designed with a novel gold working electrode that was separated from a porous counter electrode by a Nafion membrane. Because this design permitted exhaustive deposition of selenium from the sample stream as well as efficient coulometric stripping, determinations obeyed Faraday's law over a reasonably wide range of operating conditions. The method had a minimum quantitation limit of approximately 8 ng and a maximum limit of 800 ng for Se(IV). It was reliable for sample volumes as small as 0.5 mL and as high as 20 mL, thereby allowing determinations from part-per-million to just below part-per-billion levels. Interferences from Cu(II) and arsenate were evident, but only when these species were present at concentrations exceeding 10 mg.L-1. Overall, the method had a performance comparable to hydride-generation atomic absorption spectrometry but with less cumbersome equipment and freedom from calibration.
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Affiliation(s)
- Sandra G Hazelton
- Department of Chemistry, University of North Dakota, Grand Forks, North Dakota 58202-9024, USA
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Latshaw JD, Morishita TY, Sarver CF, Thilsted J. Selenium Toxicity in Breeding Ring-Necked Pheasants (Phasianus colchicus). Avian Dis 2004; 48:935-9. [PMID: 15666878 DOI: 10.1637/7177-030904r] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A flock of breeding ring-necked pheasants received feed with a high selenium content. Within 4 days of eating the toxic feed, the rate of egg production began to decrease, and bird aggression increased. Approximately 12% of the hens died within a week. Necropsy of the hens revealed colorless fluid around the heart and a friable, but otherwise normal, liver. The rapid onset of the problem and signs noted at necropsy suggested toxicosis. Based on analysis, the feed contained 9.3 ppm of selenium. Selenium toxicity was consistent with the histologic diagnosis of degenerative cardiomyopathy, vacuolar degeneration of hepatocytes, and centrilobular hepatic necrosis. After 8 days, the toxic feed was removed and replaced with fresh feed. Egg production, which had dropped to 50%, returned to normal within 10 days of feed replacement. Hatchability of eggs laid from days 8 to 14 after delivery of the toxic feed was 35%. Approximately 10% of the chicks that hatched had deformed beaks and abnormal eyes. Many of the chicks that died in the shell had deformities, bringing the total to more than 50% of all embryos that developed. The selenium content of eggs that had no embryonic development was 2.05 ppm. Hatchability of eggs laid from days 21 to 28 after the toxic feed was delivered was almost 80%, which was slightly lower than normal. The selenium content of these eggs was 0.30 ppm. These results show the rapid onset and correction of selenium toxicity and suggest that specific embryologic defects are diagnostic for selenium toxicity.
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Affiliation(s)
- J D Latshaw
- Department of Animal Sciences, Veterinary Extension Ohio State University, 1920 Coffey Road, Columbus, OH 43210, USA
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