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Dianne F Jolley - One of the best experts on this subject based on the ideXlab platform.
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assessing the effects of bioturbation on metal Bioavailability in contaminated sediments by diffusive gradients in thin films dgt
Environmental Science & Technology, 2016Co-Authors: Elvio D Amato, Timothy M Remaili, Stuart L Simpson, David A Spadaro, Chad V Jarolimek, Dianne F JolleyAbstract:The burrowing and feeding activities of benthic organisms can alter metal speciation in sediments and affect an organisms’ exposure to metals. Recently, the performance of the in situ technique of diffusive gradients in thin films (DGT) for predicting metal Bioavailability has been investigated in response to the increasing demand of considering Contaminant Bioavailability in sediment quality assessments. In this study, we test the ability of the DGT technique for predicting the metal Bioavailability in clean and contaminated sediments that are being subjected to varying degrees of sediments disturbance: low bioturbation (bivalve Tellina deltoidalis alone) and high bioturbation (bivalve and actively burrowing amphipod, Victoriopisa australiensis). Significant release of DGT-labile Cd, Ni, Pb, and Zn, but lower Cu and Fe, occurred in the pore and overlying waters of sediments exposed to high bioturbation conditions, resulting in higher bioaccumulation of zinc in bivalves. Strong relationships were found be...
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the impact of sediment bioturbation by secondary organisms on metal Bioavailability bioaccumulation and toxicity to target organisms in benthic bioassays implications for sediment quality assessment
Environmental Pollution, 2016Co-Authors: Timothy M Remaili, Stuart L Simpson, Elvio D Amato, David A Spadaro, Chad V Jarolimek, Dianne F JolleyAbstract:Bioturbation alters the properties of sediments and modifies Contaminant Bioavailability to benthic organisms. These naturally occurring disturbances are seldom considered during the assessment of sediment quality. We investigated how the presence (High bioturbation) and absence (Low bioturbation) of a strongly bioturbating amphipod within three different sediments influenced metal Bioavailability, survival and bioaccumulation of metals to the bivalve Tellina deltoidalis. The concentrations of dissolved copper decreased and manganese increased with increased bioturbation. For copper a strong correlation was observed between increased bivalve survival (53–100%) and dissolved concentrations in the overlying water. Increased bioturbation intensity resulted in greater tissue concentrations for chromium and zinc in some test sediments. Overall, the results highlight the strong influence that the natural bioturbation activities from one organism may have on the risk Contaminants pose to other organisms within the local environment. The characterisation of field-based exposure conditions concerning the biotic or abiotic resuspension of sediments and the rate of attenuation of released Contaminants through dilution or readsorption may enable laboratory-based bioassay designs to be adapted to better match those of the assessed environment.
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diffusive gradients in thin films technique provide robust prediction of metal Bioavailability and toxicity in estuarine sediments
Environmental Science & Technology, 2014Co-Authors: Elvio D Amato, Stuart L Simpson, Chad V Jarolimek, Dianne F JolleyAbstract:Many sediment quality assessment frameworks incorporate Contaminant Bioavailability as a critical factor regulating toxicity in aquatic ecosystems. However, current approaches do not always adequately predict metal Bioavailability to organisms living in the oxidized sediment surface layers. The deployment of the diffusive gradients in thin films (DGT) probes in sediments allows labile metals present in pore waters and weakly bound to the particulate phase to be assessed in a time-integrated manner in situ. In this study, relationships between DGT-labile metal fluxes within 5 mm of the sediment–water interface and lethal and sublethal effects to the amphipod Melita plumulosa were assessed in a range of contaminated estuarine sediments during 10-day laboratory-based bioassays. To account for differing toxicities of metals, DGT fluxes were normalized to water (WQG) or sediment quality guidelines or toxicity thresholds specific for the amphipod. The better dose–response relationship appeared to be the one bas...
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dgt induced copper flux predicts bioaccumulation and toxicity to bivalves in sediments with varying properties
Environmental Science & Technology, 2012Co-Authors: Stuart L Simpson, Chad V Jarolimek, Heloise Yverneau, Anne Cremazy, Helen L Price, Dianne F JolleyAbstract:Many regulatory frameworks for sediment quality assessment include consideration of Contaminant Bioavailability. However, the "snap-shots" of metal Bioavailability provided by analyses of porewaters or acid-volatile sulfide-simultaneously extractable metal (AVS-SEM) relationships do not always contribute sufficient information. The use of inappropriate or inadequate information for assessing metal Bioavailability in sediments may result in incorrect assessment decisions. The technique of diffusive gradients in thin films (DGT) enables the in situ measurement of metal concentrations in waters and fluxes from sediment porewaters. We utilized the DGT technique to interpret the Bioavailability of copper to the benthic bivalve Tellina deltoidalis in sediments of varying properties contaminated with copper-based antifouling paint particles. For a concentration series of copper-paint contaminated sandy, silty-sand, and silty sediment types, DGT-probes were used to measure copper fluxes to the overlying water, at the sediment-water interface, and in deeper sediments. The overlying water copper concentrations and DGT-Cu fluxes were shown to provide excellent exposure concentration-response relationships in relation to lethal effects occurring to the copper-sensitive benthic bivalve, T. deltoidalis. The study demonstrates the strength of the DGT technique, which we expect will become frequently used for assessing metal Bioavailability in sediments.
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metal equilibration in laboratory contaminated spiked sediments used for the development of whole sediment toxicity tests
Chemosphere, 2004Co-Authors: Stuart L Simpson, Brad M Angel, Dianne F JolleyAbstract:The equilibration and Bioavailability of metals in laboratory-contaminated sediments have been investigated in order to provide better guidance on acceptable procedures for spiking sediments with metals for use in the development of whole-sediment toxicity tests. The equilibration rates of Cd, Cu, Ni and Zn spiked into three estuarine surface sediments with varying properties were investigated. Changes to sediment pH, redox potential, porewater and acid-soluble metals, acid-volatile sulfide and bacterial activity during equilibration, effects of temperature and disturbances following equilibration are reported. The addition of metals to sediments caused major decreases in pH and increases in redox potential as metals displaced iron(II) into the porewaters and added metals and iron (following oxidation) were hydrolyzed. The rates of equilibration of metals in porewaters varied considerably and were dependent on sediment and metal properties. For the oxic/sub-oxic sediments studied, metal-spikes of Cd, Cu, Ni and Zn appeared near equilibrium after 25-45, 10-15, 30-70 and 20-40 days, respectively. Acid-soluble metal concentrations decreased during the equilibration period indicating that the metals become more strongly associated with the sediments with time (less bioavailable). Bacterial activity was greatest in the sediment equilibrated at pH 7 and decreased following the addition of metals. During the equilibration period, bacterial activity increased in sediments equilibrated at pH 6, remained low in sediments at pH 8 and varied erratically in sediments at pH 7. Spiked sediments were shown to equilibrate more slowly at lower temperatures resulting in high porewater metal concentrations. Disturbances to equilibrated sediments because of sample manipulation caused significant iron(II) oxidation and losses of metals from porewaters. The importance of documenting spiking and equilibration procedures and carefully measuring and reporting sediment parameters is highlighted so that Contaminant Bioavailability and exposure pathways can be interpreted and organism sensitivity accurately determined. Recommendations are given for the preparation of metal-spiked sediments for toxicity testing purposes.
Stuart L Simpson - One of the best experts on this subject based on the ideXlab platform.
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assessing the effects of bioturbation on metal Bioavailability in contaminated sediments by diffusive gradients in thin films dgt
Environmental Science & Technology, 2016Co-Authors: Elvio D Amato, Timothy M Remaili, Stuart L Simpson, David A Spadaro, Chad V Jarolimek, Dianne F JolleyAbstract:The burrowing and feeding activities of benthic organisms can alter metal speciation in sediments and affect an organisms’ exposure to metals. Recently, the performance of the in situ technique of diffusive gradients in thin films (DGT) for predicting metal Bioavailability has been investigated in response to the increasing demand of considering Contaminant Bioavailability in sediment quality assessments. In this study, we test the ability of the DGT technique for predicting the metal Bioavailability in clean and contaminated sediments that are being subjected to varying degrees of sediments disturbance: low bioturbation (bivalve Tellina deltoidalis alone) and high bioturbation (bivalve and actively burrowing amphipod, Victoriopisa australiensis). Significant release of DGT-labile Cd, Ni, Pb, and Zn, but lower Cu and Fe, occurred in the pore and overlying waters of sediments exposed to high bioturbation conditions, resulting in higher bioaccumulation of zinc in bivalves. Strong relationships were found be...
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the impact of sediment bioturbation by secondary organisms on metal Bioavailability bioaccumulation and toxicity to target organisms in benthic bioassays implications for sediment quality assessment
Environmental Pollution, 2016Co-Authors: Timothy M Remaili, Stuart L Simpson, Elvio D Amato, David A Spadaro, Chad V Jarolimek, Dianne F JolleyAbstract:Bioturbation alters the properties of sediments and modifies Contaminant Bioavailability to benthic organisms. These naturally occurring disturbances are seldom considered during the assessment of sediment quality. We investigated how the presence (High bioturbation) and absence (Low bioturbation) of a strongly bioturbating amphipod within three different sediments influenced metal Bioavailability, survival and bioaccumulation of metals to the bivalve Tellina deltoidalis. The concentrations of dissolved copper decreased and manganese increased with increased bioturbation. For copper a strong correlation was observed between increased bivalve survival (53–100%) and dissolved concentrations in the overlying water. Increased bioturbation intensity resulted in greater tissue concentrations for chromium and zinc in some test sediments. Overall, the results highlight the strong influence that the natural bioturbation activities from one organism may have on the risk Contaminants pose to other organisms within the local environment. The characterisation of field-based exposure conditions concerning the biotic or abiotic resuspension of sediments and the rate of attenuation of released Contaminants through dilution or readsorption may enable laboratory-based bioassay designs to be adapted to better match those of the assessed environment.
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diffusive gradients in thin films technique provide robust prediction of metal Bioavailability and toxicity in estuarine sediments
Environmental Science & Technology, 2014Co-Authors: Elvio D Amato, Stuart L Simpson, Chad V Jarolimek, Dianne F JolleyAbstract:Many sediment quality assessment frameworks incorporate Contaminant Bioavailability as a critical factor regulating toxicity in aquatic ecosystems. However, current approaches do not always adequately predict metal Bioavailability to organisms living in the oxidized sediment surface layers. The deployment of the diffusive gradients in thin films (DGT) probes in sediments allows labile metals present in pore waters and weakly bound to the particulate phase to be assessed in a time-integrated manner in situ. In this study, relationships between DGT-labile metal fluxes within 5 mm of the sediment–water interface and lethal and sublethal effects to the amphipod Melita plumulosa were assessed in a range of contaminated estuarine sediments during 10-day laboratory-based bioassays. To account for differing toxicities of metals, DGT fluxes were normalized to water (WQG) or sediment quality guidelines or toxicity thresholds specific for the amphipod. The better dose–response relationship appeared to be the one bas...
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dgt induced copper flux predicts bioaccumulation and toxicity to bivalves in sediments with varying properties
Environmental Science & Technology, 2012Co-Authors: Stuart L Simpson, Chad V Jarolimek, Heloise Yverneau, Anne Cremazy, Helen L Price, Dianne F JolleyAbstract:Many regulatory frameworks for sediment quality assessment include consideration of Contaminant Bioavailability. However, the "snap-shots" of metal Bioavailability provided by analyses of porewaters or acid-volatile sulfide-simultaneously extractable metal (AVS-SEM) relationships do not always contribute sufficient information. The use of inappropriate or inadequate information for assessing metal Bioavailability in sediments may result in incorrect assessment decisions. The technique of diffusive gradients in thin films (DGT) enables the in situ measurement of metal concentrations in waters and fluxes from sediment porewaters. We utilized the DGT technique to interpret the Bioavailability of copper to the benthic bivalve Tellina deltoidalis in sediments of varying properties contaminated with copper-based antifouling paint particles. For a concentration series of copper-paint contaminated sandy, silty-sand, and silty sediment types, DGT-probes were used to measure copper fluxes to the overlying water, at the sediment-water interface, and in deeper sediments. The overlying water copper concentrations and DGT-Cu fluxes were shown to provide excellent exposure concentration-response relationships in relation to lethal effects occurring to the copper-sensitive benthic bivalve, T. deltoidalis. The study demonstrates the strength of the DGT technique, which we expect will become frequently used for assessing metal Bioavailability in sediments.
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metal equilibration in laboratory contaminated spiked sediments used for the development of whole sediment toxicity tests
Chemosphere, 2004Co-Authors: Stuart L Simpson, Brad M Angel, Dianne F JolleyAbstract:The equilibration and Bioavailability of metals in laboratory-contaminated sediments have been investigated in order to provide better guidance on acceptable procedures for spiking sediments with metals for use in the development of whole-sediment toxicity tests. The equilibration rates of Cd, Cu, Ni and Zn spiked into three estuarine surface sediments with varying properties were investigated. Changes to sediment pH, redox potential, porewater and acid-soluble metals, acid-volatile sulfide and bacterial activity during equilibration, effects of temperature and disturbances following equilibration are reported. The addition of metals to sediments caused major decreases in pH and increases in redox potential as metals displaced iron(II) into the porewaters and added metals and iron (following oxidation) were hydrolyzed. The rates of equilibration of metals in porewaters varied considerably and were dependent on sediment and metal properties. For the oxic/sub-oxic sediments studied, metal-spikes of Cd, Cu, Ni and Zn appeared near equilibrium after 25-45, 10-15, 30-70 and 20-40 days, respectively. Acid-soluble metal concentrations decreased during the equilibration period indicating that the metals become more strongly associated with the sediments with time (less bioavailable). Bacterial activity was greatest in the sediment equilibrated at pH 7 and decreased following the addition of metals. During the equilibration period, bacterial activity increased in sediments equilibrated at pH 6, remained low in sediments at pH 8 and varied erratically in sediments at pH 7. Spiked sediments were shown to equilibrate more slowly at lower temperatures resulting in high porewater metal concentrations. Disturbances to equilibrated sediments because of sample manipulation caused significant iron(II) oxidation and losses of metals from porewaters. The importance of documenting spiking and equilibration procedures and carefully measuring and reporting sediment parameters is highlighted so that Contaminant Bioavailability and exposure pathways can be interpreted and organism sensitivity accurately determined. Recommendations are given for the preparation of metal-spiked sediments for toxicity testing purposes.
Elvio D Amato - One of the best experts on this subject based on the ideXlab platform.
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assessing the effects of bioturbation on metal Bioavailability in contaminated sediments by diffusive gradients in thin films dgt
Environmental Science & Technology, 2016Co-Authors: Elvio D Amato, Timothy M Remaili, Stuart L Simpson, David A Spadaro, Chad V Jarolimek, Dianne F JolleyAbstract:The burrowing and feeding activities of benthic organisms can alter metal speciation in sediments and affect an organisms’ exposure to metals. Recently, the performance of the in situ technique of diffusive gradients in thin films (DGT) for predicting metal Bioavailability has been investigated in response to the increasing demand of considering Contaminant Bioavailability in sediment quality assessments. In this study, we test the ability of the DGT technique for predicting the metal Bioavailability in clean and contaminated sediments that are being subjected to varying degrees of sediments disturbance: low bioturbation (bivalve Tellina deltoidalis alone) and high bioturbation (bivalve and actively burrowing amphipod, Victoriopisa australiensis). Significant release of DGT-labile Cd, Ni, Pb, and Zn, but lower Cu and Fe, occurred in the pore and overlying waters of sediments exposed to high bioturbation conditions, resulting in higher bioaccumulation of zinc in bivalves. Strong relationships were found be...
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the impact of sediment bioturbation by secondary organisms on metal Bioavailability bioaccumulation and toxicity to target organisms in benthic bioassays implications for sediment quality assessment
Environmental Pollution, 2016Co-Authors: Timothy M Remaili, Stuart L Simpson, Elvio D Amato, David A Spadaro, Chad V Jarolimek, Dianne F JolleyAbstract:Bioturbation alters the properties of sediments and modifies Contaminant Bioavailability to benthic organisms. These naturally occurring disturbances are seldom considered during the assessment of sediment quality. We investigated how the presence (High bioturbation) and absence (Low bioturbation) of a strongly bioturbating amphipod within three different sediments influenced metal Bioavailability, survival and bioaccumulation of metals to the bivalve Tellina deltoidalis. The concentrations of dissolved copper decreased and manganese increased with increased bioturbation. For copper a strong correlation was observed between increased bivalve survival (53–100%) and dissolved concentrations in the overlying water. Increased bioturbation intensity resulted in greater tissue concentrations for chromium and zinc in some test sediments. Overall, the results highlight the strong influence that the natural bioturbation activities from one organism may have on the risk Contaminants pose to other organisms within the local environment. The characterisation of field-based exposure conditions concerning the biotic or abiotic resuspension of sediments and the rate of attenuation of released Contaminants through dilution or readsorption may enable laboratory-based bioassay designs to be adapted to better match those of the assessed environment.
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diffusive gradients in thin films technique provide robust prediction of metal Bioavailability and toxicity in estuarine sediments
Environmental Science & Technology, 2014Co-Authors: Elvio D Amato, Stuart L Simpson, Chad V Jarolimek, Dianne F JolleyAbstract:Many sediment quality assessment frameworks incorporate Contaminant Bioavailability as a critical factor regulating toxicity in aquatic ecosystems. However, current approaches do not always adequately predict metal Bioavailability to organisms living in the oxidized sediment surface layers. The deployment of the diffusive gradients in thin films (DGT) probes in sediments allows labile metals present in pore waters and weakly bound to the particulate phase to be assessed in a time-integrated manner in situ. In this study, relationships between DGT-labile metal fluxes within 5 mm of the sediment–water interface and lethal and sublethal effects to the amphipod Melita plumulosa were assessed in a range of contaminated estuarine sediments during 10-day laboratory-based bioassays. To account for differing toxicities of metals, DGT fluxes were normalized to water (WQG) or sediment quality guidelines or toxicity thresholds specific for the amphipod. The better dose–response relationship appeared to be the one bas...
Timothy M Remaili - One of the best experts on this subject based on the ideXlab platform.
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assessing the effects of bioturbation on metal Bioavailability in contaminated sediments by diffusive gradients in thin films dgt
Environmental Science & Technology, 2016Co-Authors: Elvio D Amato, Timothy M Remaili, Stuart L Simpson, David A Spadaro, Chad V Jarolimek, Dianne F JolleyAbstract:The burrowing and feeding activities of benthic organisms can alter metal speciation in sediments and affect an organisms’ exposure to metals. Recently, the performance of the in situ technique of diffusive gradients in thin films (DGT) for predicting metal Bioavailability has been investigated in response to the increasing demand of considering Contaminant Bioavailability in sediment quality assessments. In this study, we test the ability of the DGT technique for predicting the metal Bioavailability in clean and contaminated sediments that are being subjected to varying degrees of sediments disturbance: low bioturbation (bivalve Tellina deltoidalis alone) and high bioturbation (bivalve and actively burrowing amphipod, Victoriopisa australiensis). Significant release of DGT-labile Cd, Ni, Pb, and Zn, but lower Cu and Fe, occurred in the pore and overlying waters of sediments exposed to high bioturbation conditions, resulting in higher bioaccumulation of zinc in bivalves. Strong relationships were found be...
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the impact of sediment bioturbation by secondary organisms on metal Bioavailability bioaccumulation and toxicity to target organisms in benthic bioassays implications for sediment quality assessment
Environmental Pollution, 2016Co-Authors: Timothy M Remaili, Stuart L Simpson, Elvio D Amato, David A Spadaro, Chad V Jarolimek, Dianne F JolleyAbstract:Bioturbation alters the properties of sediments and modifies Contaminant Bioavailability to benthic organisms. These naturally occurring disturbances are seldom considered during the assessment of sediment quality. We investigated how the presence (High bioturbation) and absence (Low bioturbation) of a strongly bioturbating amphipod within three different sediments influenced metal Bioavailability, survival and bioaccumulation of metals to the bivalve Tellina deltoidalis. The concentrations of dissolved copper decreased and manganese increased with increased bioturbation. For copper a strong correlation was observed between increased bivalve survival (53–100%) and dissolved concentrations in the overlying water. Increased bioturbation intensity resulted in greater tissue concentrations for chromium and zinc in some test sediments. Overall, the results highlight the strong influence that the natural bioturbation activities from one organism may have on the risk Contaminants pose to other organisms within the local environment. The characterisation of field-based exposure conditions concerning the biotic or abiotic resuspension of sediments and the rate of attenuation of released Contaminants through dilution or readsorption may enable laboratory-based bioassay designs to be adapted to better match those of the assessed environment.
Mark Tibbett - One of the best experts on this subject based on the ideXlab platform.
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the role of root exuded low molecular weight organic anions in facilitating petroleum hydrocarbon degradation current knowledge and future directions
Science of The Total Environment, 2014Co-Authors: Belinda C Martin, Suman George, Charles A Price, Megan H Ryan, Mark TibbettAbstract:Rhizoremediation is a bioremediation technique whereby enhanced microbial degradation of organic Contaminants occurs within the plant root zone (rhizosphere). It is considered an effective and affordable ‘green technology’ for remediating soils contaminated with petroleum hydrocarbons (PHCs). This paper critically reviews the potential role of root exuded compounds in rhizoremediation, with emphasis on commonly exuded low molecular weight aliphatic organic acid anions (carboxylates). The extent to which remediation is achieved shows wide disparity among plant species. Therefore, plant selection is crucial for the advancement and widespread adoption of this technology. Root exudation is speculated to be one of the predominant factors leading to microbial changes in the rhizosphere and thus the potential driver behind enhanced petroleum biodegradation. Carboxylates can form a significant component of the root exudate mixture and are hypothesised to enhance petroleum biodegradation by: i) providing an easily degradable energy source; ii) increasing phosphorus supply; and/or iii) enhancing the Contaminant Bioavailability. These differing hypotheses, which are not mutually exclusive, require further investigation to progress our understanding of plant–microbe interactions with the aim to improve plant species selection and the efficacy of rhizoremediation.