1
|
Schmidt MP, Mamet SD, Senger C, Schebel A, Ota M, Tian TW, Aziz U, Stein LY, Regier T, Stanley K, Peak D, Siciliano SD. Positron-emitting radiotracers spatially resolve unexpected biogeochemical relationships linked with methane oxidation in Arctic soils. Glob Chang Biol 2022; 28:4211-4224. [PMID: 35377512 DOI: 10.1111/gcb.16188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 03/21/2022] [Accepted: 03/26/2022] [Indexed: 06/14/2023]
Abstract
Arctic soils are marked by cryoturbic features, which impact soil-atmosphere methane (CH4 ) dynamics vital to global climate regulation. Cryoturbic diapirism alters C/N chemistry within frost boils by introducing soluble organic carbon and nutrients, potentially influencing microbial CH4 oxidation. CH4 oxidation in soils, however, requires a spatio-temporal convergence of ecological factors to occur. Spatial delineation of microbial activity with respect to these key microbial and biogeochemical factors at relevant scales is experimentally challenging in inherently complex and heterogeneous natural soil matrices. This work aims to overcome this barrier by spatially linking microbial CH4 oxidation with C/N chemistry and metagenomic characteristics. This is achieved by using positron-emitting radiotracers to visualize millimeter-scale active CH4 uptake areas in Arctic soils with and without diapirism. X-ray absorption spectroscopic speciation of active and inactive areas shows CH4 uptake spatially associates with greater proportions of inorganic N in diapiric frost boils. Metagenomic analyses reveal Ralstonia pickettii associates with CH4 uptake across soils along with pertinent CH4 and inorganic N metabolism associated genes. This study highlights the critical relationship between CH4 and N cycles in Arctic soils, with potential implications for better understanding future climate. Furthermore, our experimental framework presents a novel, widely applicable strategy for unraveling ecological relationships underlying greenhouse gas dynamics under global change.
Collapse
Affiliation(s)
- Michael P Schmidt
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
- USDA-ARS United States Salinity Laboratory, Riverside, California, USA
| | - Steven D Mamet
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Curtis Senger
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Alixandra Schebel
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Mitsuaki Ota
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Tony W Tian
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Umair Aziz
- Department of Computer Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Lisa Y Stein
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Tom Regier
- Canadian Light Source, Inc., Saskatoon, Saskatchewan, Canada
| | - Kevin Stanley
- Department of Computer Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Derek Peak
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Steven D Siciliano
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| |
Collapse
|
2
|
Elikem E, Persico AP, Bulmer D, Siciliano SD, Mussone P, Peak D. A sustainable colloidal material with sorption and nutrient-supply capabilities for in situ groundwater bioremediation. J Environ Qual 2021; 50:1440-1451. [PMID: 34647326 DOI: 10.1002/jeq2.20293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 09/22/2021] [Indexed: 06/13/2023]
Abstract
Microbial degradation of subsurface organic contaminants is often hindered by the low availability of both contaminants and nutrients, especially phosphorus (P). The use of activated carbon and traditional P fertilizers to overcome these challenges has proved ineffective; therefore, we sought to find an innovative and effective solution. By heating bone meal-derived organic residues in water in a closed reactor, we synthesized nonporous colloids composed of aromatic and aliphatic structures linked to P groups. X-ray absorption near edge spectroscopy analysis revealed that the materials contain mostly bioavailable forms of P (i.e., adsorbed P and magnesium-bearing brushite). The capacity of the materials to adsorb organic contaminants was investigated using benzene and batch isotherm experiments. The adsorption isotherms were fitted to the linearized Freundlich model; isotherm capacity (logKF ) values for the materials ranged between 1.6 and 2.8 μg g-1 . These results indicate that the colloidal materials have a high affinity for organic contaminants. This, coupled with their possession of bioavailable P, should make them effective amendments for in situ groundwater bioremediation. Also, the materials' chemical properties suggest that they are not recalcitrant, implying that they will not become potential contaminants when released into the environment.
Collapse
Affiliation(s)
- Essouassi Elikem
- Dep. of Soil Science, Univ. of Saskatchewan, 51 Campus Drive, Saskatoon, SK, S7N 5A8, Canada
| | - Arantxa P Persico
- Applied BioNanotechnology Industrial Research, Northern Alberta Institute of Technology, 10210 Princess Elizabeth Avenue NW, Edmonton, AB, T5G 0Y2, Canada
| | - David Bulmer
- Dep. of Soil Science, Univ. of Saskatchewan, 51 Campus Drive, Saskatoon, SK, S7N 5A8, Canada
| | - Steven D Siciliano
- Dep. of Soil Science, Univ. of Saskatchewan, 51 Campus Drive, Saskatoon, SK, S7N 5A8, Canada
| | - Paolo Mussone
- Applied BioNanotechnology Industrial Research, Northern Alberta Institute of Technology, 10210 Princess Elizabeth Avenue NW, Edmonton, AB, T5G 0Y2, Canada
| | - Derek Peak
- Dep. of Soil Science, Univ. of Saskatchewan, 51 Campus Drive, Saskatoon, SK, S7N 5A8, Canada
| |
Collapse
|
3
|
Whitaker AH, Austin RE, Holden KL, Jones JL, Michel FM, Peak D, Thompson A, Duckworth OW. The Structure of Natural Biogenic Iron (Oxyhydr)oxides Formed in Circumneutral pH Environments. Geochim Cosmochim Acta 2021; 308:237-255. [PMID: 34305159 PMCID: PMC8294128 DOI: 10.1016/j.gca.2021.05.059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Biogenic iron (Fe) (oxyhydr)oxides (BIOS) partially control the cycling of organic matter, nutrients, and pollutants in soils and water via sorption and redox reactions. Although recent studies have shown that the structure of BIOS resembles that of two-line ferrihydrite (2LFh), we lack detailed knowledge of the BIOS local coordination environment and structure required to understand the drivers of BIOS reactivity in redox active environments. Therefore, we used a combination of microscopy, scattering, and spectroscopic methods to elucidate the structure of BIOS sampled from a groundwater seep in North Carolina and compare them to 2LFh. We also simulated the effects of wet-dry cycles by varying sample preparation (e.g., freezing, flash freezing with freeze drying, freezing with freeze drying and oven drying). In general, the results show that both the long- and short-range ordering in BIOS are structurally distinct and notably more disordered than 2LFh. Our structure analysis, which utilized Fe K-edge X-ray absorption spectroscopy, Mössbauer spectroscopy, X-ray diffraction, and pair distribution function analyses, showed that the BIOS samples were more poorly ordered than 2LFh and intimately mixed with organic matter. Furthermore, pair distribution function analyses resulted in coherent scattering domains for the BIOS samples ranging from 12-18 Å, smaller than those of 2LFh (21-27 Å), consistent with reduced ordering. Additionally, Fe L-edge XAS indicated that the local coordination environment of 2LFh samples consisted of minor amounts of tetrahedral Fe(III), whereas BIOS were dominated by octahedral Fe(III), consistent with depletion of the sites due to small domain size and incorporation of impurities (e.g., organic C, Al, Si, P). Within sample sets, the frozen freeze dried and oven dried sample preparation increased the crystallinity of the 2LFh samples when compared to the frozen treatment, whereas the BIOS samples remained more poorly crystalline under all sample preparations. This research shows that BIOS formed in circumneutral pH waters are poorly ordered and more environmentally stable than 2LFh.
Collapse
Affiliation(s)
- Andrew H. Whitaker
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Robert E. Austin
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Kathryn L. Holden
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Jacob L. Jones
- Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - F. Marc Michel
- Department of Geosciences, Virginia Tech, Blacksburg, Virginia 24060, USA
| | - Derek Peak
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, Canada
| | - Aaron Thompson
- Department of Crop and Soil Sciences, University of Georgia, Athens, Georgia 30602, USA
| | - Owen W. Duckworth
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, North Carolina 27695, USA
| |
Collapse
|
4
|
Schmidt MP, Siciliano SD, Peak D. The role of monodentate tetrahedral borate complexes in boric acid binding to a soil organic matter analogue. Chemosphere 2021; 276:130150. [PMID: 33721632 DOI: 10.1016/j.chemosphere.2021.130150] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 02/24/2021] [Accepted: 02/27/2021] [Indexed: 06/12/2023]
Abstract
Boron is an essential plant micronutrient responsible for several important functions. Boron availability in soils may be influenced by binding with soil organic matter (SOM), particularly with aromatic diol and polyphenol groups on SOM. The mechanism by which aromatic diols bind boron, however, remains unclear. The objective of this work is to further investigate interaction between boric acid and varying concentrations of an aromatic, polyphenolic SOM analogue (tannic acid at 5, 10 and 20 g L-1) from pH = 5-9. UV/Visible spectroscopy showed boric acid enhanced tannic acid deprotonation at pH = 7.0 and 9.0, resulting in singly deprotonated tannic acid subunits. Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) showed boric acid/tannic acid binding for all concentrations at pH = 7 and 9, whereas binding at pH = 5.0 was observed only at 20 g L-1 tannic acid. Uncomplexed boron species were not evident at pH = 9.0, but were detectable at pH = 7.0 at lower tannic acid concentrations and prevalent at pH = 5.0, qualitatively indicating binding affinity increases from pH = 5.0 to 9.0. ATR-FTIR results indicated tetrahedral coordination of boron upon complexation to tannic acid with a monodentate mechanism. These results collectively highlight a transition of solution planar boric acid to a tetrahedral, monodentate coordination with a single phenol group in tannic acid polyphenols. This contrasts with previous spectroscopic studies, which indicated bidentate tetrahedral or monodentate trigonal planar orientations prevail at aromatic diol sites. This work presents a previously unobserved boric acid coordination mechanism to an SOM analogue and, therefore, may better inform prediction and modeling of boron behavior in soils.
Collapse
Affiliation(s)
- Michael P Schmidt
- Department of Soil Science, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, SK S7N 5A8, Canada.
| | - Steven D Siciliano
- Department of Soil Science, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, SK S7N 5A8, Canada
| | - Derek Peak
- Department of Soil Science, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, SK S7N 5A8, Canada
| |
Collapse
|
5
|
Mamet SD, Jimmo A, Conway A, Teymurazyan A, Talebitaher A, Papandreou Z, Chang YF, Shannon W, Peak D, Siciliano SD. Soil Buffering Capacity Can Be Used To Optimize Biostimulation of Psychrotrophic Hydrocarbon Remediation. Environ Sci Technol 2021; 55:9864-9875. [PMID: 34170682 DOI: 10.1021/acs.est.1c01113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Effective bioremediation of hydrocarbons requires innovative approaches to minimize phosphate precipitation in soils of different buffering capacities. Understanding the mechanisms underlying sustained stimulation of bacterial activity remains a key challenge for optimizing bioremediation-particularly in northern regions. Positron emission tomography (PET) can trace microbial activity within the naturally occurring soil structure of intact soils. Here, we use PET to test two hypotheses: (1) optimizing phosphate bioavailability in soil will outperform a generic biostimulatory solution in promoting hydrocarbon remediation and (2) oligotrophic biostimulation will be more effective than eutrophic approaches. In so doing, we highlight the key bacterial taxa that underlie aerobic and anaerobic hydrocarbon degradation in subarctic soils. In particular, we showed that (i) optimized phosphate bioavailability outperformed generic biostimulatory solutions in promoting hydrocarbon degradation, (ii) oligotrophic biostimulation is more effective than eutrophic approaches, and (iii) optimized biostimulatory solutions stimulated specific soil regions and bacterial consortia. The knowledge gleaned from this study will be crucial in developing field-scale biodegradation treatments for sustained stimulation of bacterial activity in northern regions.
Collapse
Affiliation(s)
- Steven D Mamet
- College of Agriculture and Bioresources, Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, Canada
| | - Amy Jimmo
- College of Agriculture and Bioresources, Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, Canada
| | - Alexandra Conway
- College of Agriculture and Bioresources, Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, Canada
| | - Aram Teymurazyan
- Department of Physics, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Alizera Talebitaher
- Department of Physics, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Zisis Papandreou
- Department of Physics, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Yu-Fen Chang
- Department of Physics, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
- Department of Mechanical and Marine Engineering, Western Norway University of Applied Sciences, Bergen 5063, Norway
- Nuclear Medicine and Radiation Biology Research Group, Department of Clinical Medicine, UiT The Arctic University of Norway, 9037 Tromsø, Norway
| | - Whitney Shannon
- College of Agriculture and Bioresources, Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, Canada
- Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5C9, Canada
| | - Derek Peak
- College of Agriculture and Bioresources, Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, Canada
| | - Steven D Siciliano
- College of Agriculture and Bioresources, Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, Canada
| |
Collapse
|
6
|
Abstract
Positron-emitting nuclides have long been used as imaging agents in medical science to spatially trace processes non-invasively, allowing for real-time molecular imaging using low tracer concentrations. This ability to non-destructively visualize processes in real time also makes positron imaging uniquely suitable for probing various processes in plants and porous environmental media, such as soils and sediments. Here, we provide an overview of historical and current applications of positron imaging in environmental research. We highlight plant physiological research, where positron imaging has been used extensively to image dynamics of macronutrients, signalling molecules, trace elements, and contaminant metals under various conditions and perturbations. We describe how positron imaging is used in porous soils and sediments to visualize transport, flow, and microbial metabolic processes. We also address the interface between positron imaging and other imaging approaches, and present accompanying chemical analysis of labelled compounds for reviewed topics, highlighting the bridge between positron imaging and complementary techniques across scales. Finally, we discuss possible future applications of positron imaging and its potential as a nexus of interdisciplinary biogeochemical research.
Collapse
Affiliation(s)
- Michael P Schmidt
- Department of Soil Science, College of Agriculture and Bioresources, 7235University of Saskatchewan, Saskatoon, Canada
| | - Steven D Mamet
- Department of Soil Science, College of Agriculture and Bioresources, 7235University of Saskatchewan, Saskatoon, Canada
| | - Richard A Ferrieri
- Interdisciplinary Plant Group, Division of Plant Sciences, Department of Chemistry, Missouri Research Reactor Center, 14716University of Missouri, Columbia, MO, USA
| | - Derek Peak
- Department of Soil Science, College of Agriculture and Bioresources, 7235University of Saskatchewan, Saskatoon, Canada
| | - Steven D Siciliano
- Department of Soil Science, College of Agriculture and Bioresources, 7235University of Saskatchewan, Saskatoon, Canada
| |
Collapse
|
7
|
Jun YS, Zhu M, Peak D. Frontiers and advances in environmental soil chemistry: a special issue in honor of Prof. Donald L. Sparks. Geochem Trans 2020; 21:6. [PMID: 32303855 PMCID: PMC7164233 DOI: 10.1186/s12932-020-00070-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Affiliation(s)
- Young-Shin Jun
- Department of Energy, Environmental & Chemical Engineering, Washington University, St. Louis, MO 63130 USA
| | - Mengqiang Zhu
- Department of Ecosystem Science and Management, University of Wyoming, Laramie, WY 82071 USA
| | - Derek Peak
- Department of Soil Science, University of Saskatchewan, Saskatoon, SK S7N 5A8 Canada
| |
Collapse
|
8
|
McQuillan AJ, Osawa M, Peak D, Ren B, Tian ZQ. Experiments on adsorption at hydrous metal oxide surfaces using attenuated total reflection infrared spectroscopy (ATRIRS) (IUPAC Technical Report). PURE APPL CHEM 2019. [DOI: 10.1515/pac-2019-0211] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
This article seeks to encourage the adoption of modern methods of surface analysis in teaching contexts by introducing the use of attenuated total reflection infrared spectroscopy (ATRIRS) in analysis of adsorption reactions at hydrous metal oxide thin films. The first experiment shows how outer-sphere adsorption of perchlorate ion is distinguished from inner-sphere adsorption of ethanedioate (oxalate) ion at TiO2 surfaces. The second experiment shows how the nature of adsorption of sulfate ion to iron oxide surfaces changes with pH. In the third experiment, the variation of the amount of benzene-1,2-diol (catechol) adsorbed to TiO2 with solution concentration enables an adsorption constant to be derived from the adsorption isotherm.
Collapse
Affiliation(s)
| | - Masatoshi Osawa
- Catalysis Research Centre , Hokkaido University , Sapporo , Japan
| | - Derek Peak
- Department of Soil Science , University of Saskatewan , Saskatoon , Canada
| | - Bin Ren
- Department of Chemistry , Xiamen University , Xiamen , China
| | - Zhong-Qun Tian
- Department of Chemistry , Xiamen University , Xiamen , China
| |
Collapse
|
9
|
Lounsbury AW, Wang R, Plata DL, Billmyer N, Muhich C, Kanie K, Sugimoto T, Peak D, Zimmerman JB. Preferential adsorption of selenium oxyanions onto {1 1 0} and {0 1 2} nano-hematite facets. J Colloid Interface Sci 2019; 537:465-474. [DOI: 10.1016/j.jcis.2018.11.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Revised: 11/02/2018] [Accepted: 11/07/2018] [Indexed: 10/27/2022]
|
10
|
Elikem E, Laird BD, Hamilton JG, Stewart KJ, Siciliano SD, Peak D. Effects of chemical speciation on the bioaccessibility of zinc in spiked and smelter-affected soils. Environ Toxicol Chem 2019; 38:448-459. [PMID: 30525224 DOI: 10.1002/etc.4328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 10/12/2018] [Accepted: 12/03/2018] [Indexed: 06/09/2023]
Abstract
Previous studies have suggested that understanding soil metal speciation, rather than relying solely on total metal content, can improve the accuracy and utility of contaminated site risk assessments. Because soil properties and reaction time can alter metal speciation, speciation should influence metal bioaccessibility. For example, under gastrointestinal conditions, it is expected that metal species will differ in bioaccessibility depending on their stability in acidic pH environments. We studied the links between metal speciation and bioaccessibility. A combination of synchrotron-based X-ray diffraction and X-ray absorption near edge structure (XANES) was used to identify the zinc (Zn) speciation in spiked and smelter-affected soils. After conducting in vitro digestion tests on the soil samples, XANES and linear combination fitting were carried out on the residual pellets to identify the species of Zn that remained after digesting the soils in the simulated gastric and duodenal fluids. The metal species that were not present in the residual pellets were inferred to have been dissolved and, thus, more bioaccessible. Sphalerite (ZnS), ZnO, and outer-sphere Zn contributed more to Zn bioaccessibility than franklinite (ZnFe2 O4 ) and Zn incorporated into a hydroxy interlayer mineral (Zn-HIM). The bioaccessibility of Zn-aluminum layered double hydroxides (Zn-Al-LDH) was found to be inversely proportional to its residence time in soil. It was also observed that the relatively high pH of the duodenum favors metal reprecipitation and readsorption, leading to a reduction in bioaccessible metal concentration. These results imply that metal speciation mainly controls metal bioaccessibility. Environ Toxicol Chem 2019;38:448-459. © 2018 SETAC.
Collapse
Affiliation(s)
- Essouassi Elikem
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Brian D Laird
- School of Public Health and Health Systems, University of Waterloo, Waterloo, Ontario, Canada
| | - Jordan G Hamilton
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Katherine J Stewart
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Steven D Siciliano
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Derek Peak
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| |
Collapse
|
11
|
Godiwala P, Humm K, Comstock I, Witmyer J, Peak D, Sparks A, Lalwani S, Frankfurter D. Performance of retrieved oocytes that mature from metaphase I (MI) to metaphase II (MII) after a GnRH agonist trigger. Fertil Steril 2018. [DOI: 10.1016/j.fertnstert.2018.07.881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
12
|
Grant K, Comstock I, Humm K, Lalwani S, Peak D, Witmyer J, Frankfurter D. Trophectodermal euploidy rates as a function of time to blastocoele expansion. Fertil Steril 2018. [DOI: 10.1016/j.fertnstert.2018.07.981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
13
|
Saibu Y, Kumar S, Jamwal A, Peak D, Niyogi S. A FTIRM study of the interactive effects of metals (zinc, copper and cadmium) in binary mixtures on the biochemical constituents of the gills in rainbow trout (Oncorhynchus mykiss). Comp Biochem Physiol C Toxicol Pharmacol 2018; 211:48-56. [PMID: 29803893 DOI: 10.1016/j.cbpc.2018.05.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Revised: 05/22/2018] [Accepted: 05/22/2018] [Indexed: 10/16/2022]
Abstract
We employed Fourier Transform Infrared Microspectroscopy to examine, in situ, the effects of waterborne Cu, Cd and Zn, alone and in binary mixtures, during acute exposure on the integrity of major lipid and protein constituents of the gill of a model teleost species, rainbow trout (Oncorhynchus mykiss). Our findings demonstrated that acute exposure to metals, both individually and in binary mixture, resulted in the degradations of various components of proteins and lipids in the gill tissue. Generally, when comparing the effects of individual metals, Cu was found to induce the maximum adverse effects followed by Cd and Zn, respectively. Among the binary metal-mixture combinations, Cu and Cd produced additive effects on the degradation of major proteins and lipid moieties, whereas the co-exposure of Zn with Cd or Cu elicited ameliorative effects, indicating antagonistic (less than additive) interactions between Zn and Cd or Cu in the rainbow trout gill. Overall, the present study demonstrates that FTIRM can be a useful tool to gain novel mechanistic insights into the biochemical changes induced by metals in the fish gill, which could influence the overall toxicity of metals to fish.
Collapse
Affiliation(s)
- Yusuf Saibu
- Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK, Canada.
| | - Saroj Kumar
- Dept. of Engineering Sciences, Uppsala University, Uppsala, Sweden; Dept. of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - Ankur Jamwal
- Dept. of Biology, University of Saskatchewan, 112 Science Place, Saskatoon, SK, Canada
| | - Derek Peak
- Dept. of Soil Science, University of Saskatchewan, 114 Science Place, Saskatoon, SK, Canada
| | - Som Niyogi
- Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK, Canada; Dept. of Biology, University of Saskatchewan, 112 Science Place, Saskatoon, SK, Canada
| |
Collapse
|
14
|
Saibu Y, Jamwal A, Feng R, Peak D, Niyogi S. Distribution and speciation of zinc in the gills of rainbow trout (Oncorhynchus mykiss) during acute waterborne zinc exposure: Interactions with cadmium or copper. Comp Biochem Physiol C Toxicol Pharmacol 2018; 206-207:23-31. [PMID: 29501824 DOI: 10.1016/j.cbpc.2018.02.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 02/21/2018] [Accepted: 02/25/2018] [Indexed: 11/18/2022]
Abstract
We utilized micro X-ray fluorescence imaging (μ-XFI) and micro X-ray absorption near-edge spectroscopy (μ-XANES), which are both synchrotron-based techniques to investigate Zn distribution profile, its co-localization patterns with Ca, S, and Fe and speciation in the gills of rainbow trout (RBT). Fish (~100 g) were exposed to acutely toxic levels of waterborne Zn alone and in combination with waterborne Cd or Cu for 24 h (each at 1 × 96 h LC50). Gill sections were prepared and analyzed at the VESPERS beamline of the Canadian Light Source. The primary lamellae of the fish gill were found to be the primary area of Zn accumulation. These regions also correspond to the zones of mitochondria rich cells localization in fish gills, supporting the putative roles of these cells in metal uptake. Zn was also found to predominantly co-localize with Ca and S, but not with Fe, indicating the roles of Ca and S in intracellular Zn handling. Zn distribution in the gill was markedly reduced during co-exposure to Cd, but not to Cu, suggesting a competitive interaction between Zn and Cd for uptake. The speciation of Zn in the gill was dominated by Zn-phosphate, Zn-histidine and Zn-cysteine species; however, the interactions of Zn with Cd or Cu resulted in the loss of Zn-cysteine. Overall, our findings provide important novel insights into the interactions of Zn, Cd and Cu in the fish gill, which may ultimately help to explain the mechanisms underlying the acute toxicity of these metals in binary mixture to fish.
Collapse
Affiliation(s)
- Yusuf Saibu
- Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK, Canada.
| | - Ankur Jamwal
- Department of Biology, University of Saskatchewan, 112 Science Place, Saskatoon, SK, Canada
| | - Renfei Feng
- Canadian Light Source Incorporated, 44 Innovation Blvd, Saskatoon, SK, Canada
| | - Derek Peak
- Department of Soil Science, University of Saskatchewan, 114 Science Place, Saskatoon, SK, Canada
| | - Som Niyogi
- Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK, Canada; Department of Biology, University of Saskatchewan, 112 Science Place, Saskatoon, SK, Canada
| |
Collapse
|
15
|
Alotaibi KD, Schoenau JJ, Kar G, Peak D, Fonstad T. Phosphorus speciation in a prairie soil amended with MBM and DDG ash: Sequential chemical extraction and synchrotron-based XANES spectroscopy investigations. Sci Rep 2018; 8:3617. [PMID: 29483601 PMCID: PMC5827736 DOI: 10.1038/s41598-018-21935-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 02/14/2018] [Indexed: 11/09/2022] Open
Abstract
Sequential chemical extraction and synchrotron-based XANES spectroscopy techniques were used to identify P species in two ashes before and after addition to a prairie soil. The used ashes were: meat and bone meal ash (MBMA) and dried distillers grains ash (DDGA) plus mineral P fertilizer (MP) for comparison. Soil treated with MP contained higher content of resin-Pi and NaHCO3-Pi followed by DDGA and MBMA. The MBMA amended soil had the highest (47%) proportion of the soil P contained in recalcitrant HCl extractable fraction, reflecting more Ca-bound P present and being formed in soil after application. Analysis of both ashes with XANES spectroscopy before application to soil revealed that MBMA had strong spectral features consistent with hydroxyapatite (Ca5(PO4)3(OH)). DDGA exhibited spectral features consistent with a mixture of several Mg and K phosphate salts rather than a single mineral species. The distinctive features in the XANES spectra of both ashes largely disappeared after amendment to the soil, suggesting transformation to different P forms in the soil after application. It is also possible that the added amount of P to the studied soil via DDGS or MBMA was small enough so that P speciation is not different from the background P level.
Collapse
Affiliation(s)
- Khaled D Alotaibi
- Department of Soil Science, King Saud University, Box 2460, Riyadh, 11451, Saudi Arabia. .,Department of Soil Science, University of Saskatchewan, 51 Campus Drive, Saskatoon, Sk, S7N 5A8, Canada.
| | - Jeff J Schoenau
- Department of Soil Science, University of Saskatchewan, 51 Campus Drive, Saskatoon, Sk, S7N 5A8, Canada
| | - Gourango Kar
- Department of Soil Science, University of Saskatchewan, 51 Campus Drive, Saskatoon, Sk, S7N 5A8, Canada
| | - Derek Peak
- Department of Soil Science, University of Saskatchewan, 51 Campus Drive, Saskatoon, Sk, S7N 5A8, Canada
| | - Terry Fonstad
- Department of Chemical and Biological Engineering, University of Saskatchewan, 51 Campus Drive, Saskatoon, Sk, S7N 5A9, Canada
| |
Collapse
|
16
|
Hamilton JG, Grosskleg J, Hilger D, Bradshaw K, Carlson T, Siciliano SD, Peak D. Chemical speciation and fate of tripolyphosphate after application to a calcareous soil. Geochem Trans 2018; 19:1. [PMID: 29313216 PMCID: PMC5758486 DOI: 10.1186/s12932-017-0046-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 12/19/2017] [Indexed: 06/07/2023]
Abstract
Adsorption and precipitation reactions often dictate the availability of phosphorus in soil environments. Tripolyphosphate (TPP) is considered a form of slow release P fertilizer in P limited soils, however, investigations of the chemical fate of TPP in soils are limited. It has been proposed that TPP rapidly hydrolyzes in the soil solution before adsorbing or precipitating with soil surfaces, but in model systems, TPP also adsorbs rapidly onto mineral surfaces. To study the adsorption behavior of TPP in calcareous soils, a short-term (48 h) TPP spike was performed under laboratory conditions. To determine the fate of TPP under field conditions, two different liquid TPP amendments were applied to a P limited subsurface field site via an in-ground injection system. Phosphorus speciation was assessed using X-ray absorption spectroscopy, total and labile extractable P, and X-ray diffraction. Adsorption of TPP to soil mineral surfaces was rapid (< 48 h) and persisted without fully hydrolyzing to ortho-P. Linear combination fitting of XAS data indicated that the distribution of adsorbed P was highest (~ 30-40%) throughout the site after the first TPP amendment application (high water volume and low TPP concentrations). In contrast, lower water volumes with more concentrated TPP resulted in lower relative fractions of adsorbed P (15-25%), but a significant increase in total P concentrations (~ 3000 mg P kg soil) and adsorbed P (60%) directly adjacent to the injection system. This demonstrates that TPP application increases the adsorbed P fraction of calcareous soils through rapid adsorption reactions with soil mineral surfaces.
Collapse
Affiliation(s)
- Jordan G. Hamilton
- Department of Soil Science, University of Saskatchewan, Saskatoon, SK S7N 5A8 Canada
| | - Jay Grosskleg
- Federated Cooperatives Ltd., Saskatoon, SK S7K 0H2 Canada
| | - David Hilger
- Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, ON Canada
| | - Kris Bradshaw
- Federated Cooperatives Ltd., Saskatoon, SK S7K 0H2 Canada
| | | | - Steven D. Siciliano
- Department of Soil Science, University of Saskatchewan, Saskatoon, SK S7N 5A8 Canada
| | - Derek Peak
- Department of Soil Science, University of Saskatchewan, Saskatoon, SK S7N 5A8 Canada
| |
Collapse
|
17
|
Weyers E, Strawn DG, Peak D, Baker LL. Inhibition of phosphorus sorption on calcite by dairy manure-sourced DOC. Chemosphere 2017; 184:99-105. [PMID: 28582769 DOI: 10.1016/j.chemosphere.2017.05.141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 05/10/2017] [Accepted: 05/23/2017] [Indexed: 06/07/2023]
Abstract
In confined animal feeding operations, such as dairies, manure is amended to soils at high rates leading to increases in P and organic matter in the soils. Phosphorus reacts with soil-Ca to form Ca-P minerals, which controls P availability for leaching and transport through the watershed. In this research, the effects of manure sourced dissolved organic matter (DOM) on P sorption on calcite were measured at different reaction times and concentrations. Reactions were monitored in 1% and 10% manure-to-water extract solutions spiked with P. When manure-DOM was present, a significant reduction in P sorption occurred (2-90% absolute decrease) compared to samples without manure-DOM. The greatest decrease occurred in the samples reacted in the 10% manure solution. XANES spectroscopic analysis showed that at 1% manure solution, a Ca-P phase similar to hydroxyapatite formed. In the calcite samples reacted in the 10% manure solution, K-edge XANES spectroscopy revealed that P occurred as a Ca-Mg-P phase instead of the less soluble hydroxyapatite-like phase. Results from this study suggest that in manure-amended calcareous soils, increased DOM from manure will decrease P sorption capacity and increase the overall P concentration in solution, which will increase the mobility of P and subsequently pose greater risks for impairment of surface water quality.
Collapse
Affiliation(s)
- Eva Weyers
- 875 Perimeter Dr., Department of Soil and Water Systems, University of Idaho, Moscow, ID 83844-2340, USA
| | - Daniel G Strawn
- 875 Perimeter Dr., Department of Soil and Water Systems, University of Idaho, Moscow, ID 83844-2340, USA.
| | - Derek Peak
- University of Saskatchewan, Saskatoon, SK S7N 5A2 Canada
| | - Leslie L Baker
- 875 Perimeter Dr., Department of Soil and Water Systems, University of Idaho, Moscow, ID 83844-2340, USA
| |
Collapse
|
18
|
Chen T, Philips C, Hamilton J, Chartbrand B, Grosskleg J, Bradshaw K, Carlson T, Timlick K, Peak D, Siciliano SD. Citrate Addition Increased Phosphorus Bioavailability and Enhanced Gasoline Bioremediation. J Environ Qual 2017; 46:975-983. [PMID: 28991988 DOI: 10.2134/jeq2017.02.0064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Phosphorus (P) bioavailability often limits gasoline biodegradation in calcareous cold-region soils. One possible method to increase P bioavailability in such soils is the addition of citrate. Citrate addition at the field scale may increase hydrocarbon degradation by: (i) enhancing inorganic and organic P dissolution and desorption, (ii) increasing hydrocarbon bioavailability, and/or (iii) stimulating microbial activity. Alternatively, citrate addition may inhibit activity due to competitive effects on carbon metabolism. Using a field-scale in situ biostimulation study, we evaluated if citrate could stimulate gasoline degradation and what the dominant mechanism of this stimulation will be. Two large bore injectors were constructed at a site contaminated with gasoline, and a biostimulation solution of 11 mM MgSO, 1 mM HPO, and 0.08 mM HNO at pH 6.5 in municipal potable water was injected at ∼5000 L d for about 4 mo. Following this, 10 mM citric acid was incorporated into the existing biostimulation solution and the site continued to be stimulated for 8 mo. After citrate addition, the bioavailable P fraction in groundwater and soil increased. Iron(II) groundwater concentrations increased and corresponded to decreases in benzene, toluene, ethylbenzene, xylenes (BTEX) in groundwater, as well as a decrease in F1 in the soil saturated zone. Overall, citrate addition increased P bioavailability and may stimulate anaerobic microbial activity, resulting in accelerated anaerobic gasoline bioremediation in cold-region calcareous soils.
Collapse
|
19
|
Hamilton JG, Hilger D, Peak D. Mechanisms of tripolyphosphate adsorption and hydrolysis on goethite. J Colloid Interface Sci 2017; 491:190-198. [DOI: 10.1016/j.jcis.2016.12.036] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 12/14/2016] [Accepted: 12/15/2016] [Indexed: 11/28/2022]
|
20
|
Hamilton JG, Farrell RE, Chen N, Reid J, Feng R, Peak D. Effects of Dolomitic Limestone Application on Zinc Speciation in Boreal Forest Smelter-Contaminated Soils. J Environ Qual 2016; 45:1894-1900. [PMID: 27898799 DOI: 10.2134/jeq2016.06.0231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Anthropogenic activities at the HudBay Minerals, Inc., Flin Flon (Manitoba, Canada) mining and processing facility have severely affected the surrounding boreal forest ecosystem. Soil contamination occurred via a combination of metal and sulfuric acid deposition and has resulted in forest dieback and ineffective natural recovery. A community-led effort to revegetate areas of the landscape through the application of a dolomitic limestone has been met with varied success. Zinc (Zn) speciation has shown to be closely linked to the presence or absence of an invasive metal-tolerant grass species, with soils being broadly classed into two revegetation response groups. Group I, characterized by the absence of metal-tolerant grasses, and group II, characterized by the presence of metal-tolerant grasses. The systematic approach used to lime areas of the landscape produced a liming chronosequence for each group. This study used a combination of X-ray absorption spectroscopy, X-ray fluorescence mapping, and X-ray diffraction techniques to determine the effect of liming on Zn speciation in these chronosequences. Liming group I soils resulted in the formation of a neo-phase Zn-Al-hydroxy interlayer coprecipitate and subsequent rapid boreal forest revegetation. The effect of liming on Zn speciation on the group II soils resulted in a gradual transition of increasingly stable adsorption species, culminating with a stable Zn-Al-layered double hydroxide precipitate. Boreal forest vegetation has failed to recolonize group II soils during the study. However, the formation of the layered double hydroxide species resulted in a significant reduction in CaCl-extractable Zn. Further research is required to determine how to promote the revegetation of these soils.
Collapse
|
21
|
Siciliano SD, Chen T, Phillips C, Hamilton J, Hilger D, Chartrand B, Grosskleg J, Bradshaw K, Carlson T, Peak D. Total Phosphate Influences the Rate of Hydrocarbon Degradation but Phosphate Mineralogy Shapes Microbial Community Composition in Cold-Region Calcareous Soils. Environ Sci Technol 2016; 50:5197-5206. [PMID: 27082646 DOI: 10.1021/acs.est.5b05911] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Managing phosphorus bioaccessibility is critical for the bioremediation of hydrocarbons in calcareous soils. This paper explores how soil mineralogy interacts with a novel biostimulatory solution to both control phosphorus bioavailability and influence bioremediation. Two large bore infiltrators (1 m diameter) were installed at a PHC contaminated site and continuously supplied with a solution containing nutrients and an electron acceptor. Soils from eight contaminated sites were prepared and pretreated, analyzed pretrial, spiked with diesel, placed into nylon bags into the infiltrators, and removed after 3 months. From XAS, we learned that three principal phosphate phases had formed: adsorbed phosphate, brushite, and newberyite. All measures of biodegradation in the samples (in situ degradation estimates, mineralization assays, culturable bacteria, catabolic genes) varied depending upon the soil's phosphate speciation. Notably, adsorbed phosphate increased anaerobic phenanthrene degradation and bzdN catabolic gene prevalence. The dominant mineralogical constraints on community composition were the relative amounts of adsorbed phosphate, brushite, and newberyite. Overall, this study finds that total phosphate influences microbial community phenotypes whereas relative percentages of phosphate minerals influences microbial community genotype composition.
Collapse
Affiliation(s)
- Steven D Siciliano
- Department of Soil Science, University of Saskatchewan , Saskatoon S7N 5A8, Canada
| | - Tingting Chen
- Department of Soil Science, University of Saskatchewan , Saskatoon S7N 5A8, Canada
| | - Courtney Phillips
- Department of Soil Science, University of Saskatchewan , Saskatoon S7N 5A8, Canada
| | - Jordan Hamilton
- Department of Soil Science, University of Saskatchewan , Saskatoon S7N 5A8, Canada
| | - David Hilger
- Department of Soil Science, University of Saskatchewan , Saskatoon S7N 5A8, Canada
| | | | - Jay Grosskleg
- Federated Cooperatives Limited, Saskatoon S7N 5A8, Canada
| | - Kris Bradshaw
- Federated Cooperatives Limited, Saskatoon S7N 5A8, Canada
| | - Trevor Carlson
- Federated Cooperatives Limited, Saskatoon S7N 5A8, Canada
| | - Derek Peak
- Department of Soil Science, University of Saskatchewan , Saskatoon S7N 5A8, Canada
| |
Collapse
|
22
|
Jones L, Borstov A, Fillingim R, Peak D, Kurz M, Hendry P, Rathlev N, Swor R, Domeier R, Damiron K, Pearson C, Kaushik S, Feldman J, McLean S. (100) African Americans experience a greater burden of acute pain after motor vehicle collision than European Americans. The Journal of Pain 2016. [DOI: 10.1016/j.jpain.2016.01.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
23
|
Hamilton JG, Farrell RE, Chen N, Feng R, Reid J, Peak D. Characterizing Zinc Speciation in Soils from a Smelter-Affected Boreal Forest Ecosystem. J Environ Qual 2016; 45:684-692. [PMID: 27065416 DOI: 10.2134/jeq2015.03.0145] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
HudBay Minerals, Inc., has mined and/or processed Zn and Cu ore in Flin Flon, MB, Canada, since the 1930s. The boreal forest ecosystem and soil surrounding these facilities have been severely impacted by mixed metal contamination and HSO deposition. Zinc is one of the most prevalent smelter-derived contaminants and has been identified as a key factor that may be limiting revegetation. Metal toxicity is related to both total concentrations and speciation; therefore, X-ray absorption spectroscopy and X-ray fluorescence mapping were used to characterize Zn speciation in soils throughout the most heavily contaminated areas of the landscape. Zinc speciation was linked to two distinct soil types. Group I soils consist of exposed soils in weathered positions of bedrock outcrops with Zn present primarily as franklinite, a (ZnFeO) spinel mineral. Group II soils are stabilized by an invasive metal-tolerant grass species, with Zn found as a mixture of octahedral (Fe oxides) and tetrahedral Mn oxides) adsorption complexes with a franklinite component. Soil erosion influences Zn speciation through the redistribution of Zn and soil particulates from Group I landscape positions to Group II soils. Despite Group II soils having the highest concentrations of CaCl-extractable Zn, they support metal-tolerant plant growth. The metal-tolerant plants are probably preferentially colonizing these areas due to better soil and nutrient conditions as a result of soil deposition from upslope Group I areas. Zinc concentration and speciation appears to not influence the colonization by metal-tolerant grasses, but the overall soil properties and erosion effects prevent the revegetation by native boreal forest species.
Collapse
|
24
|
Levine M, Pizon A, Stellpflug S, Wiegand T, Villano J, Peak D, Thomas S. 387 Hypoglycemia in Acetaminophen-Induced Hepatic Failure: What Is the Significance? Ann Emerg Med 2015. [DOI: 10.1016/j.annemergmed.2015.07.423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
25
|
Laird BD, Weiseth B, Packull-McCormick SR, Peak D, Dodd M, Siciliano SD. Solid-liquid separation method governs the in vitro bioaccessibility of metals in contaminated soil-like test materials. Chemosphere 2015; 134:544-549. [PMID: 25600322 DOI: 10.1016/j.chemosphere.2014.12.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 11/25/2014] [Accepted: 12/04/2014] [Indexed: 06/04/2023]
Abstract
An in vitro gastrointestinal model was used to explore the role of solid-liquid separation method on the bioaccessibility of trace elements in a smelter-impacted soil (NIST-2711) from Helena, MT and a mine overburden from an open-pit gold and silver mine in Mount Nansen, YK (YK-OVB). Separation methods studied included centrifugation (5,000 g, 12,000 g), syringe microfiltration (0.45 μm), and ultrafiltration (1,000 kDa, 50 kDa, 30 kDa, 10 kDa, 3 kDa). Results indicated that the use of syringe microfiltration generally yields the same bioaccessibility as the use of centrifugation and that the speed of centrifugation does not typically affect metal bioaccessibility. However, ultrafiltration consistently yields a significantly lower bioaccessibility than the use of centrifugation and syringe microfiltration. There are rarely any differences between bioaccessibility estimates generated using a low-resistance (1,000 kDa) and a high-resistance (3 kDa) ultrafiltration membrane; therefore, under the in vitro gastrointestinal conditions modeled herein, negligible quantities of trace elements are complexed to small molecules between 3 and 1,000 kDa. The primary exceptions to these trends were observed for Pb in NIST-2711 (5,000 g>12,000 g>0.45 μm>ultrafiltration) and for Tl in NIST-2711 and YK-OVB (5000 g∼12,000 g>0.45 μm>ultrafiltration). These results provide valuable information to researchers attempting to expand the use of in vitro bioaccessibility beyond soil Pb and As.
Collapse
Affiliation(s)
- Brian D Laird
- School of Public Health and Health Systems, University of Waterloo, Waterloo, Ontario, Canada.
| | - Blake Weiseth
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | | | - Derek Peak
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Matt Dodd
- Royal Roads University, Victoria, British Columbia, Canada
| | - Steven D Siciliano
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| |
Collapse
|
26
|
Dynes JJ, Regier TZ, Snape I, Siciliano SD, Peak D. Validating the scalability of soft X-ray spectromicroscopy for quantitative soil ecology and biogeochemistry research. Environ Sci Technol 2015; 49:1035-1042. [PMID: 25526317 DOI: 10.1021/es505271p] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Synchrotron-based soft-X-ray scanning transmission X-ray microscopy (STXM) has the potential to provide nanoscale resolution of the associations among biological and geological materials. However, standard methods for how samples should be prepared, measured, and analyzed to allow the results from these nanoscale imaging and spectroscopic tools to be scaled to field scale biogeochemical results are not well established. We utilized a simple sample preparation technique that allows one to assess detailed mineral, metal, and microbe spectroscopic information at the nano- and microscale in soil colloids. We then evaluated three common approaches to collect and process nano- and micronscale information by STXM and the correspondence of these approaches to millimeter scale soil measurements. Finally, we assessed the reproducibility and spatial autocorrelation of nano- and micronscale protein, Fe(II) and Fe(III) densities in a soil sample. We demonstrate that linear combination fitting of entire spectra provides slightly different Fe(II) mineral densities compared to image resonance difference mapping but that difference mapping results are highly reproducible between among sample replicates. Further, STXM results scale to the mm scale in complex systems with an approximate geospatial range of 3 μm in these samples.
Collapse
|
27
|
Bortsov A, Miller W, Soward A, Swor R, Peak D, Jones J, Rathlev N, Lee D, Domeier R, Hendry P, McLean S. (145) Derivation of an emergency department-based clinical prediction tool to identify individuals at increased risk of chronic musculoskeletal pain development after motor vehicle collision. The Journal of Pain 2014. [DOI: 10.1016/j.jpain.2014.01.051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
28
|
Green RJ, Peak D, Achkar AJ, Tse JS, Moewes A, Hawthorn DG, Regier TZ. Comment on "State-dependent electron delocalization dynamics at the solute-solvent interface: soft-x-ray absorption spectroscopy and ab initio calculations". Phys Rev Lett 2014; 112:129301. [PMID: 24724686 DOI: 10.1103/physrevlett.112.129301] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Indexed: 06/03/2023]
Affiliation(s)
- R J Green
- Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5E2
| | - D Peak
- Department of Soil Science, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5A8
| | - A J Achkar
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - J S Tse
- Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5E2
| | - A Moewes
- Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5E2
| | - D G Hawthorn
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - T Z Regier
- Canadian Light Source, Inc., Saskatoon, Saskatchewan, Canada S7N 2V3
| |
Collapse
|
29
|
Yang J, Liu J, Dynes JJ, Peak D, Regier T, Wang J, Zhu S, Shi J, Tse JS. Speciation and distribution of copper in a mining soil using multiple synchrotron-based bulk and microscopic techniques. Environ Sci Pollut Res Int 2014; 21:2943-2954. [PMID: 24170498 DOI: 10.1007/s11356-013-2214-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 10/02/2013] [Indexed: 06/02/2023]
Abstract
Molecular-level understanding of soil Cu speciation and distribution assists in management of Cu contamination in mining sites. In this study, one soil sample, collected from a mining site contaminated since 1950s, was characterized complementarily by multiple synchrotron-based bulk and spatially resolved techniques for the speciation and distribution of Cu as well as other related elements (Fe, Ca, Mn, K, Al, and Si). Bulk X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy revealed that soil Cu was predominantly associated with Fe oxides instead of soil organic matter. This agreed with the closest association of Cu to Fe by microscopic X-ray fluorescence (U-XRF) and scanning transmission X-ray microscopy (STXM) nanoanalysis, along with the non-occurrence of photoreduction of soil Cu(II) by quick Cu L3,2-edge XANES spectroscopy (Q-XANES) which often occurs when Cu organic complexes are present. Furthermore, bulk-EXAFS and STXM-coupled Fe L3,2-edge nano-XANES analysis revealed soil Cu adsorbed primarily to Fe(III) oxides by inner-sphere complexation. Additionally, Cu K-edge μ-XANES, L3,2-edge bulk-XANES, and successive Q-XANES results identified the presence of Cu2S rather than radiation-damage artifacts dominant in certain microsites of the mining soil. This study demonstrates the great benefits in use of multiple combined synchrotron-based techniques for comprehensive understanding of Cu speciation in heterogeneous soil matrix, which facilitates our prediction of Cu reactivity and environmental fate in the mining site.
Collapse
Affiliation(s)
- Jianjun Yang
- Department of Environmental Engineering, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, People's Republic of China
| | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Phillips CL, Regier TZ, Peak D. Aqueous Cu(II)-organic complexation studied in situ using soft X-ray and vibrational spectroscopies. Environ Sci Technol 2013; 47:14290-14297. [PMID: 24261818 DOI: 10.1021/es401643e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
In situ aqueous solutions containing copper-ligand mixtures were measured at the Cu L-edge using X-ray absorption near edge structure (XANES) and with attenuated total reflectance infrared (ATR-FTIR) spectroscopies. Copper complexation with environmentally relevant ligands such as EDTA, citrate, and malate provided a bridge between spectroscopic studies and general environmental behavior and will allow for future study of complex environmental samples. XANES results show that the lowest unoccupied molecular orbital (LUMO) energy is governed by the ligand field strength and is related to Lewis acid/base properties of the ligand functional groups. Complementary ATR-FTIR studies confirmed the importance of water molecules in the structure of these Cu-ligand complexes and provided in-depth structural analysis to support the XANES data. Copper-malate is shown to have a 5/6-O-ring structure, and Cu-ethylenediaminetetraacetate has pentadentate coordination. Cu L-edge XANES also revealed direct Cu-N coordination in these aqueous solutions with amide functional groups.
Collapse
Affiliation(s)
- Courtney L Phillips
- Department of Soil Science, University of Saskatchewan , Saskatoon, Saskatchewan, Canada
| | | | | |
Collapse
|
31
|
Abstract
Biochars produced from meat and bonemeal (MBM) waste materials contain large amounts of calcium phosphate and are potentially useful sorbents for the remediation of metals. Because the reactivity of biochars depends strongly upon the conditions used in their production, the objective of this study was to evaluate the rates and mechanisms of Zn sorption onto a commercially supplied MBM biochar prior to its application in a field-scale revegetation project. Sorption experiments varying pH, time, and Zn concentration found that, above pH 6.1, Zn adsorbed to MBM biochar quickly (within 5 h) with a maximum adsorption capacity of 0.65 mmol Zn g(-1). Synchrotron-based Zn K-edge extended X-ray absorption fine structure spectroscopy was consistent with a tetrahedral Zn bound to phosphate groups in a monodentate inner-sphere surface complex for all conditions tested. With an acidification pretreatment and at more acidic pH, MBM biochar causes precipitation of a ZnPO4 phase. On the basis of these results, this MBM biochar has a high capacity to rapidly adsorb Zn in adsorption experiments and can be considered a promising sorbent for Zn remediation of contaminated soils.
Collapse
Affiliation(s)
- Aaron R Betts
- Oak Ridge Institute for Science and Education , U.S. Environmental Protection Agency, Cincinnati, Ohio 45268, United States
| | | | | | | |
Collapse
|
32
|
Regier TZ, Achkar AJ, Peak D, Tse JS, Hawthorn DG. Dark channel fluorescence observations result from concentration effects rather than solvent–solute charge transfer. Nat Chem 2012; 4:765-6; author reply 767-8. [DOI: 10.1038/nchem.1430] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
33
|
Misra S, Peak D, Chen N, Hamilton C, Niyogi S. Tissue-specific accumulation and speciation of selenium in rainbow trout (Oncorhynchus mykiss) exposed to elevated dietary selenomethionine. Comp Biochem Physiol C Toxicol Pharmacol 2012; 155:560-5. [PMID: 22261037 DOI: 10.1016/j.cbpc.2012.01.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Revised: 12/25/2011] [Accepted: 01/05/2012] [Indexed: 11/28/2022]
Abstract
The toxicity of selenium in fish is influenced by its chemical speciation and the exposure route. In the natural environment, selenium exposure to fish occurs primarily in the form of selenomethionine in diet. Thus, the main objective of this study was to examine the tissue-specific selenium burden and speciation in fish exposed to elevated dietary selenomethionine. Rainbow trout (Oncorhynchus mykiss) were treated with dietary selenomethionine (40 μg g(-1) dry mass) for 2 weeks, and at the end of the exposure different tissue samples were collected to assess the tissue-specific distribution and speciation of selenium. We used synchrotron-based X-ray absorption near edge spectroscopy (XANES) to determine the selenium speciation profile. Selenomethionine, selenocysteine and selenocystine were found to be the predominant form of selenium in all of the tissues; however their relative proportion varied across different tissues. In general, the organs primarily involved in selenium handling in fish (e.g., liver, kidney) accumulated a higher percentage of selenocystine. We also found that dietary selenomethionine exposure resulted into a marked increase in selenium burden of all major tissues in fish including the brain. Collectively, our findings provide new insights into the tissue-specific distribution and speciation of selenium in fish exposed to selenomethionine via diet.
Collapse
Affiliation(s)
- Sougat Misra
- Department of Biology, 112 Science Place, University of Saskatchewan, Saskatoon, Saskatchewan, Canada, S7N 5E2
| | | | | | | | | |
Collapse
|
34
|
Abstract
Ferrihydrite is a common iron hydroxide nanomineral commonly found in soils, sediments, and surface waters. Reactivity with this important environmental surface often controls the fate and mobility of both essential nutrients and inorganic contaminants. Despite the critical role of ferrihydrite in environmental geochemistry, its structure is still debated. In this work, we apply bulk sensitive Fe L edge X-ray absorption spectroscopy to study the crystal field environment of the Fe in ferrihydrite and other Fe oxides of known structure. This direct probe of the local electronic structure provides verification of the presence of tetrahedrally coordinated Fe(III) in the structure of ferrihydrite and puts to rest the controversy on this issue.
Collapse
Affiliation(s)
- Derek Peak
- Department of Soil Science, College of Agriculture and Bioresources, University of Saskatchewan, 51 Campus Drive, Saskatoon, Saskatchewan, Canada S7N 5A8.
| | | |
Collapse
|
35
|
Penn J, Borczuk P, Peak D. 326 Identification of Patients With Traumatic Intracranial Hemorrhage Who Are at Low Risk for Deterioration or Neurosurgical Intervention. Ann Emerg Med 2011. [DOI: 10.1016/j.annemergmed.2011.06.357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
36
|
Yang J, Regier T, Dynes JJ, Wang J, Shi J, Peak D, Zhao Y, Hu T, Chen Y, Tse JS. Soft X-ray Induced Photoreduction of Organic Cu(II) Compounds Probed by X-ray Absorption Near-Edge (XANES) Spectroscopy. Anal Chem 2011; 83:7856-62. [DOI: 10.1021/ac201622g] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jianjun Yang
- Institute of Environmental Science and Technology, Zhejiang University, Hangzhou 310029, P.R. China
- Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Canada S7N 5E2
| | - Tom Regier
- Canadian Light Source Inc., University of Saskatchewan, Saskatoon, Canada S7N 0X4
| | - James J. Dynes
- Canadian Light Source Inc., University of Saskatchewan, Saskatoon, Canada S7N 0X4
| | - Jian Wang
- Canadian Light Source Inc., University of Saskatchewan, Saskatoon, Canada S7N 0X4
| | - Jiyan Shi
- Institute of Environmental Science and Technology, Zhejiang University, Hangzhou 310029, P.R. China
| | - Derek Peak
- Department of Soil Science, University of Saskatchewan, Saskatoon, Canada S7N 5A8
| | - Yidong Zhao
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Science, Beijing 100049, P.R. China
| | - Tiandou Hu
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Science, Beijing 100049, P.R. China
| | - Yingxu Chen
- Institute of Environmental Science and Technology, Zhejiang University, Hangzhou 310029, P.R. China
| | - John S Tse
- Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Canada S7N 5E2
| |
Collapse
|
37
|
Laird BD, Peak D, Siciliano SD. Bioaccessibility of metal cations in soil is linearly related to its water exchange rate constant. Environ Sci Technol 2011; 45:4139-4144. [PMID: 21466150 DOI: 10.1021/es103710a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Site-specific risk assessments often incorporate the concepts of bioaccessibility (i.e., contaminant fraction released into gastrointestinal fluids) or bioavailability (i.e., contaminant fraction absorbed into systemic circulation) into the calculation of ingestion exposure. We evaluated total and bioaccessible metal concentrations for 19 soil samples under simulated stomach and duodenal conditions using an in vitro gastrointestinal model. We demonstrated that the median bioaccessibility of 23 metals ranged between <1 and 41% under simulated stomach conditions and < 1 and 63% under simulated duodenal conditions. Notably, these large differences in metal bioaccessibility were independent of equilibrium solubility and stability constants. Instead, the relationship (stomach phase R = 0.927; duodenum phase R = 0.891) between bioaccessibility and water exchange rates of metal cations (k(H₂O)) indicated that desorption kinetics may influence if not control metal bioaccessibility.
Collapse
Affiliation(s)
- Brian D Laird
- Interdisciplinary Graduate Program of Toxicology, University of Saskatchewan, Saskatoon, Canada
| | | | | |
Collapse
|
38
|
Dubey A, Dayal M, Peak D, Khaldi R, Frankfurter D, Gindoff P. Prefered day of embryo transfer (day 4 vs day 5) of normal PGD embryos depends on develpomental stage. Fertil Steril 2010. [DOI: 10.1016/j.fertnstert.2010.07.514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
39
|
Misra S, Peak D, Niyogi S. Application of XANES spectroscopy in understanding the metabolism of selenium in isolated rainbow trout hepatocytes: insights into selenium toxicity. Metallomics 2010; 2:710-7. [DOI: 10.1039/c0mt00008f] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
40
|
Laird BD, Peak D, Siciliano SD. The effect of residence time and fluid volume to soil mass (LS) ratio on in vitro arsenic bioaccessibility from poorly crystalline scorodite. J Environ Sci Health A Tox Hazard Subst Environ Eng 2010; 45:732-739. [PMID: 20401772 DOI: 10.1080/10934521003648958] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Percent arsenic bioaccessibility is occasionally dependent upon arsenic concentration; however, the mechanism(s) of this relationship has not yet been defined. To evaluate the mechanism of this relationship, the arsenic bioaccessibility from freshly synthesized poorly crystalline scorodite was measured in the stomach, small intestine, and colon stages of the Simulator of the Human Intestinal Microbial Ecosystem (SHIME). The shape of the arsenic dissolution isotherms were different between stages (stomach: linear; small intestine: exponential rise to maxima; colon: sigmoidal). These results indicate that arsenic bioaccessibility may be limited by either in vitro GI fluid saturation or in vitro GI model residence time, depending upon the chemical/microbiological conditions of the model. Gastrointestinal microorganisms increased arsenic bioaccessibility of scorodite up to two-fold in the SHIME colon; however, this was dependent upon the sample arsenic concentration. Up to 40% of the bioaccessible arsenic was reduced to arsenite; however this process was neither mediated by GI microorganisms nor associated with increased arsenic bioaccessibility.
Collapse
Affiliation(s)
- Brian D Laird
- Interdisciplinary Graduate Program of Toxicology, University of Saskatchewan, Saskatoon, SK, Canada.
| | | | | |
Collapse
|
41
|
Laird BD, Yeung J, Peak D, Siciliano SD. Nutritional status and gastrointestinal microbes affect arsenic bioaccessibility from soils and mine tailings in the simulator of the human intestinal microbial ecosystem. Environ Sci Technol 2009; 43:8652-8657. [PMID: 20028066 DOI: 10.1021/es900837y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In vitro gastrointestinal models, used to measure the metal(loid) bioaccessibility for site specific risk assessment, are typically operated under fasted conditions. We evaluated the hypothesis that fed conditions increase arsenic bioaccessibility on three reference soils (NIST 2711, NIST 2709, and BGS 102) and the bulk and <38 mum size fractions of a mine tailing. The three nutritional states included a fed state with a carbohydrate mixture, a second fed state with homogenized crowberries (Empetrum nigrum), and a fasted state. The carbohydrate mixture increased arsenic bioaccessibility from four of five samples in the simulator of the human intestinal microbial ecosystem (SHIME) stomach but only three of five samples in the SHIME small intestine and colon. In contrast, crowberries increased arsenic bioaccessibility from four of five samples in the SHIME small intestine but had variable affects in the SHIME stomach and colon. The effect of nutritional status on arsenic bioaccessibility was potentially mediated via ligand-promoted dissolution in the SHIME stomach and small intestine. The displacement of arsenic with phosphate was potentially present in the SHIME small intestine but not the SHIME stomach. Microbial activity increased arsenic bioaccessibility relative to sterile conditions from four of five samples under fasted conditions and three of the five samples under fed conditions, which may suggest that in vitro gastrointestinal (GI) models operated under fed conditions and with microbes provide a more conservative estimate of in vitro bioaccessibility. However, for some samples, the arsenic bioaccessibility in the SHIME colon (with microbial activity) was equivalent to values observed in a separate physiologically based extraction test under small intestinal conditions (without microbial activity). These results suggest that the incorporation of microbial activity into in vitro GI models does not necessarily make estimates of arsenic bioaccessibility more protective than those generated using in vitro models that do not include microbial activity.
Collapse
Affiliation(s)
- Brian D Laird
- Graduate Program of Toxicology, Department of Soil Science, and Toxicology Group, University of Saskatchewan, Saskatoon, SK, S7N 5A8
| | | | | | | |
Collapse
|
42
|
Dayal M, Frankfurter D, Moawad G, Peak D, Dubey A, Gindoff P. A new threshold sperm index predicts IUI outcome. Fertil Steril 2009. [DOI: 10.1016/j.fertnstert.2009.07.1237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
43
|
Frankfurter D, Dayal M, Peak D, Dubey A, Gindoff P. Profound teratospermia does not influence sex chromosomal aneuploidy rates in IVF-PGD cycles. Fertil Steril 2008. [DOI: 10.1016/j.fertnstert.2008.07.956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
44
|
Dayal M, Frankfurter D, Moawad G, Peak D, Dubey A, Gindoff P. A novel semen measure for predicting post-IUI pregnancy: the absolute motile morphology count. Fertil Steril 2008. [DOI: 10.1016/j.fertnstert.2008.07.071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
45
|
Dean M, Frankfurter D, Dayal M, Dubey A, Peak D, Gindoff P. Pregnant and non-pregnant IVF-ET cycles yield adequate endometrial development regardless of serum estradiol levels. Fertil Steril 2007. [DOI: 10.1016/j.fertnstert.2007.07.991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
46
|
Nagurney J, Moselewski F, Nichols J, Brown D, Marill K, Peak D, Harris N, Swap C, Worrell S, Halpern E, Hoffmann U. Impact of Multi-detector Computerized Axial Tomography Scan of the Coronary Arteries on the Decision to Admit Emergency Department Patients with Chest Pain and Inconclusive Emergency Department Evaluations for Acute Coronary Syndrome. Acad Emerg Med 2007. [DOI: 10.1197/j.aem.2007.03.1046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
47
|
Abstract
The fate and mobility of boric acid in the environment is largely controlled by adsorption reactions with soil organic matter and soil minerals to form surface complexes (Soil Sci Soc. Am. J. 1991, 55, 1582; Geochim. Cosmochim. Acta 2002, 67, 2551; Soil Sci. Soc. Am. J. 1995, 59, 405; Environ. Sci. Technol. 1995, 29, 302). In this study, boric acid adsorption on pure am-Al(OH)3 and 5% (w/w) humic acid (HA) coated am-Al(OH)3 were investigated both as a function of pH (4.5-11) and initial boric acid concentration (0-4.5 mmol L(-1)). Batch adsorption isotherm experiments were also conducted with samples exposed to atmospheric CO2 and anaerobic (N2) conditions to examine the effects of dissolved CO2 on boric acid adsorption. Boron (B) K-edge X-ray absorption near-edge structure (XANES) spectroscopy was used to investigate the coordination of boric acid adsorbed at mineral/water interfaces. The XANES spectra of boric acid adsorption samples showed that both trigonally and tetrahedrally coordinated B complexes were present on the mineral surface. Both macroscopic and spectroscopic experiments revealed that the combination of HA coating on am-Al(OH)3 and dissolved CO2 decreased boric acid adsorption compared to adsorption on pure am-Al(OH)3.
Collapse
Affiliation(s)
- Dani Xu
- University of Saskatchewan, 51 Campus Drive, Saskatoon, Saskatchewan, Canada S7N 5A8.
| | | |
Collapse
|
48
|
Peak D. Adsorption mechanisms of selenium oxyanions at the aluminum oxide/water interface. J Colloid Interface Sci 2006; 303:337-45. [PMID: 16949599 DOI: 10.1016/j.jcis.2006.08.014] [Citation(s) in RCA: 167] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2006] [Revised: 08/02/2006] [Accepted: 08/02/2006] [Indexed: 11/29/2022]
Abstract
Sorption processes at the mineral/water interface typically control the mobility and bioaccessibility of many inorganic contaminants such as oxyanions. Selenium is an important micronutrient for human and animal health, but at elevated concentrations selenium toxicity is a concern. The objective of this study was to determine the bonding mechanisms of selenate (SeO4(2-) and selenite (SeO3(2-) on hydrous aluminum oxide (HAO) over a wide range of reaction pH using extended X-ray absorption fine structure (EXAFS) spectroscopy. Additionally, selenate adsorption on corundum (alpha-Al2O3) was studied to determine if adsorption mechanisms change as the aluminum oxide surface structure changes. The overall findings were that selenite forms a mixture of outer-sphere and inner-sphere bidentate-binuclear (corner-sharing) surface complexes on HAO, selenate forms primarily outer-sphere surface complexes on HAO, and on corundum selenate forms outer-sphere surface complexes at pH 3.5 but inner-sphere monodentate surface complexes at pH 4.5 and above. It is possible that the lack of inner-sphere complex formation at pH 3.5 is caused by changes in the corundum surface at low pH or secondary precipitate formation. The results are consistent with a structure-based reactivity for metal oxides, wherein hydrous metal oxides form outer-sphere complexes with sulfate and selenate, but inner-sphere monodentate surface complexes are formed between sulfate and selenate and alpha-Me2O3.
Collapse
Affiliation(s)
- Derek Peak
- Department of Soil Science, University of Saskatchewan, Saskatoon, SK S7N 5A8, Canada.
| |
Collapse
|
49
|
Dubey A, Dayal M, Frankfurter D, Balazy P, Peak D, Gindoff P. O-149. Fertil Steril 2006. [DOI: 10.1016/j.fertnstert.2006.07.172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
50
|
O'Driscoll NJ, Siciliano SD, Peak D, Carignan R, Lean DRS. The influence of forestry activity on the structure of dissolved organic matter in lakes: implications for mercury photoreactions. Sci Total Environ 2006; 366:880-93. [PMID: 16257437 DOI: 10.1016/j.scitotenv.2005.09.067] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2005] [Revised: 09/13/2005] [Accepted: 09/19/2005] [Indexed: 05/04/2023]
Abstract
It is well known that dissolved organic matter (DOM) increases in lakes associated with forestry activity but characterization of the DOM structure is incomplete. Twenty-three lakes with a wide range of forestry activities located in central Quebec, Canada were sampled and analyzed for dissolved organic carbon (DOC) concentration, DOC fluorescence, and ultra violet-visible (UV-VIS) absorption spectra. The results show that DOC increases (as does the associated DOC fluorescence) with increased logging (slope=0.122, r2=0.581, p<0.001; and slope=0.283, r2=0.308, p<0.01, respectively) in the 23 lakes sampled however, the aromaticity of the DOM does not change with changes in logging (as found by UV-VIS ratios, absorbance slope in the UV region, and DOC normalized fluorescence (slope=1.42x10(-2), r2=0.331, p<0.01). The DOM from four of these lakes was concentrated using reverse osmosis (RO) followed by freeze-drying. The structures of the concentrated dissolved organic matter (DOM) samples were analyzed using X-ray analysis of near edge structures (XANES), X-ray diffraction (XRD), and 13C solid-state nuclear magnetic resonance (13C NMR) analysis. XANES analysis of functional groups in the four concentrated samples shows that there are significant differences in reduced sulphur between the samples, however there was no clear relationship with forestry activity in the associated catchment. XRD data showed the presence of amorphous sulphide minerals associated with the DOM concentrate that may be important sites for mercury binding. The 13C NMR spectra of these samples show that the percentage of carbon present in carboxylic functional groups increases with increasing logging. Such structures are important for binding photo-reducible mercury and their presence may limit mercury photo-reduction and volatilization. We propose a mechanism by which increased logging leads to increased carboxylic groups in DOM and thereby increased weak binding of photo-reducible mercury. These results, in part, explain the decrease in dissolved gaseous mercury (DGM) production rates with increased logging found in our previous work.
Collapse
Affiliation(s)
- N J O'Driscoll
- Biology Department, Faculty of Science, University of Ottawa, P.O. Box 450, Stn. A., Ottawa, Ontario, Canada, K1N 6N5.
| | | | | | | | | |
Collapse
|