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Dik Van De Meent - One of the best experts on this subject based on the ideXlab platform.
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USEtox fate and ecotoxicity factors for comparative assessment of toxic Emissions in life cycle analysis: sensitivity to key chemical properties
The International Journal of Life Cycle Assessment, 2011Co-Authors: Andrew D. Henderson, Mark A. J. Huijbregts, Thomas E. Mckone, Dik Van De Meent, Michael Z. Hauschild, Henrik Fred Larsen, Manuele Margni, Jerome Payet, Ralph K. Rosenbaum, Olivier JollietAbstract:Purpose The USEtox model was developed in a scientific consensus process involving comparison of and harmonization between existing environmental multimedia fate models. USEtox quantitatively models the continuum from chemical Emission to freshwater ecosystem toxicity via chemical-specific characterization factors (CFs) for Life Cycle Impact Assessment (LCIA). This work provides understanding of the key mechanisms and chemical parameters influencing fate in the environment and impact on aquatic ecosystems. Materials and method USEtox incorporates a matrix framework for multimedia modeling, allowing separation of fate, exposure, and ecotoxicity effects in the determination of an overall CF. Current best practices, such as incorporation of intermittent rain and effect factors (EF) based on substance toxicity across species, are implemented in the model. The USEtox database provides a dataset of over 3,000 organic chemicals, of which approximately 2,500 have freshwater EFs. Freshwater characterization factors for these substances, with a special focus on a subset of chemicals with characteristic properties, were analyzed to understand the contributions of fate, exposure, and effect on the overall CFs. The approach was based on theoretical interpretation of the multimedia model components as well as multidimensional graphical analysis. Results and discussion For direct Emission of a substance to water, the EF strongly controls freshwater ecotoxicity, with a range of up to 10 orders of magnitude. In this release scenario, chemical-specific differences in environmental fate influence the CF for freshwater Emissions by less than 2 orders of magnitude. However, for an Emission to Air or soil, the influence of the fate is more pronounced. Chemical partitioning properties between water, Air, and soil may drive intermedia transfer, which may be limited by the often uncertain, media-specific degradation half-life. Intermedia transfer may be a function of landscape parameters as well; for example, direct transfer from Air to freshwater is limited by the surface area of freshwater. Overall, these altered fate factors may decrease the CF up to 8 orders of magnitude. Conclusions This work brings new clarity to the relative contributions of fate and freshwater ecotoxicity to the calculation of CFs. In concert with the USEtox database, which provides the most extensive compilation of CFs to date, these findings enable those undertaking LCIA to understand and contextualize existing and newly calculated CFs.
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A comparison between the multimedia fate and exposure models caltox and uniform system for evaluation of substances adapted for life-cycle assessment based on the population intake fraction of toxic pollutants
Environmental Toxicology and Chemistry, 2005Co-Authors: Mark A. J. Huijbregts, Loes M.j. Geelen, Edgar G. Hertwich, Thomas E. Mckone, Dik Van De MeentAbstract:In life-cycle assessment (LCA) and comparative risk assessment, potential human exposure to toxic pollutants can be expressed as the population intake fraction (iF), which represents the fraction of the quantity emitted that enters the human population. to assess the influence of model differences in the calculation of the population iF, ingestion and inhalation iFs of 365 substances emitted to Air, freshwater, and soil were calculated with two commonly applied multimedia fate and exposure models, CaltoX and the uniform system for evaluation of substances adapted for life-cycle assessment (USES-LCA). The model comparison showed that differences in the iFs due to model choices were the lowest after Emission to Air and the highest after Emission to soil. Inhalation iFs were more sensitive to model differences compared to ingestion iFs. The choice for a continental seawater compartment, vertical stratification of the soil compartment, rain and no-rain scenarios, and drinking water purification mainly clarify the relevant model differences found in population iFs. Furthermore, pH correction of chemical properties and aerosol-associated deposition on plants appeared to be important for dissociative organics and metals emitted to Air, respectively. Finally, it was found that quantitative structure–activity relationship estimates for superhydrophobics may introduce considerable uncertainty in the calculation of population intake fractions.
Olivier Jolliet - One of the best experts on this subject based on the ideXlab platform.
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USEtox fate and ecotoxicity factors for comparative assessment of toxic Emissions in life cycle analysis: sensitivity to key chemical properties
The International Journal of Life Cycle Assessment, 2011Co-Authors: Andrew D. Henderson, Mark A. J. Huijbregts, Thomas E. Mckone, Dik Van De Meent, Michael Z. Hauschild, Henrik Fred Larsen, Manuele Margni, Jerome Payet, Ralph K. Rosenbaum, Olivier JollietAbstract:Purpose The USEtox model was developed in a scientific consensus process involving comparison of and harmonization between existing environmental multimedia fate models. USEtox quantitatively models the continuum from chemical Emission to freshwater ecosystem toxicity via chemical-specific characterization factors (CFs) for Life Cycle Impact Assessment (LCIA). This work provides understanding of the key mechanisms and chemical parameters influencing fate in the environment and impact on aquatic ecosystems. Materials and method USEtox incorporates a matrix framework for multimedia modeling, allowing separation of fate, exposure, and ecotoxicity effects in the determination of an overall CF. Current best practices, such as incorporation of intermittent rain and effect factors (EF) based on substance toxicity across species, are implemented in the model. The USEtox database provides a dataset of over 3,000 organic chemicals, of which approximately 2,500 have freshwater EFs. Freshwater characterization factors for these substances, with a special focus on a subset of chemicals with characteristic properties, were analyzed to understand the contributions of fate, exposure, and effect on the overall CFs. The approach was based on theoretical interpretation of the multimedia model components as well as multidimensional graphical analysis. Results and discussion For direct Emission of a substance to water, the EF strongly controls freshwater ecotoxicity, with a range of up to 10 orders of magnitude. In this release scenario, chemical-specific differences in environmental fate influence the CF for freshwater Emissions by less than 2 orders of magnitude. However, for an Emission to Air or soil, the influence of the fate is more pronounced. Chemical partitioning properties between water, Air, and soil may drive intermedia transfer, which may be limited by the often uncertain, media-specific degradation half-life. Intermedia transfer may be a function of landscape parameters as well; for example, direct transfer from Air to freshwater is limited by the surface area of freshwater. Overall, these altered fate factors may decrease the CF up to 8 orders of magnitude. Conclusions This work brings new clarity to the relative contributions of fate and freshwater ecotoxicity to the calculation of CFs. In concert with the USEtox database, which provides the most extensive compilation of CFs to date, these findings enable those undertaking LCIA to understand and contextualize existing and newly calculated CFs.
Maureen E Puettmann - One of the best experts on this subject based on the ideXlab platform.
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LIFE-CYCLE ANALYSIS OF WOOD PRODUCTS : CRADLE-to-GATE LCI OF RESIDENTIAL WOOD BUILDING MATERIALS
Wood Science and Technology, 2004Co-Authors: Maureen E PuettmannAbstract:This study compares the cradle-to-gate total energy and major Emissions for the extraction of raw materials, production, and transportation of the common wood building materials from the CORRIM 2004 reports. A life-cycle inventory produced the raw materials, including fuel resources and Emission to Air, water, and land for glued-laminated timbers, kiln-dried and green softwood lumber, laminated veneer lumber, softwood plywood, and oriented strandboard. Major findings from these comparisons were that the production of wood products, by the nature of the industry, uses a third of their energy consumption from renewable resources and the remainder from fossil-based, non-renewable resources when the system boundaries consider forest regeneration and harvesting, wood products and resin production, and transportation life-cycle stages. When the system boundaries are reduced to a gate-to-gate (manufacturing life-cycle stage) model for the wood products, the biomass component of the manufacturing energy increases to nearly 50% for most products and as high as 78% for lumber production from the Southeast. The manufacturing life-cycle stage consumed the most energy over all the products when resin is considered part of the production process. Extraction of log resources and transportation of raw materials for production had the least environmental impact.
Philip Owende - One of the best experts on this subject based on the ideXlab platform.
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environmental impacts of biogas deployment part i life cycle inventory for evaluation of production process Emissions to Air
Journal of Cleaner Production, 2012Co-Authors: Martina Poeschl, S M Ward, Philip OwendeAbstract:Abstract A Life Cycle Inventory (LCI) was developed to identify the unit processes in the life-cycle of biogas production and utilization offering the greatest opportunities for Emission to Air reduction, hence potential for environmental improvement. The systems investigated included single feedstock digestion and multiple feedstock co-digestion, small ( el ) and large-scale (≥500 kW el ) biogas plants, and selected biogas utilization pathways and digestate management options. Analysis was performed in accordance with ISO 14040 and 14044 standards, using SimaPro 7.2 software and Ecoinvent ® v2.1 database. The analysis is based on published data considering primarily conditions for Germany. Results indicated significant variation of Emission levels for all unit processes related to biogas production and utilization. Emissions from the feedstock supply logistics were highly influenced by the origin of feedstock used. For example, the fossil fuel related carbon dioxide (CO 2,fossil ) Emissions associated with feedstock supply were over 50 times higher for Municipal Solid Waste (MSW) compared to cattle manure. The higher value for MSW was associated with the requisite collection, transport and pre-treatment, whereas only transportation was required for cattle manure. Emissions from unit processes in biogas plant operation and biogas utilization depended on combined efficiency of energy generation (electricity and thermal), potential substitution of fossil fuels with biogas and utilization of the heat by-product of electricity generation. For example, the results indicated that upgrading of biogas to biomethane, with almost 100% conversion efficiency, caused 6 times less non-methane volatile organic compounds (NMVOC) Emissions if plant heating was supplied from coupled small-scale CHP unit as opposed to heating with natural gas. Harnessing of the residual biogas from digestate storage areas was estimated to reduce methane Emission by a factor up to 14. Overall, this study provides basic data required for identification and mitigation of Emission ‘hot-spots’ in biogas production and utilization, including the evaluation of environmental and public health impacts of biogas technology options by attributional Life Cycle Assessment (LCA) methodology.
Mark A. J. Huijbregts - One of the best experts on this subject based on the ideXlab platform.
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USEtox fate and ecotoxicity factors for comparative assessment of toxic Emissions in life cycle analysis: sensitivity to key chemical properties
The International Journal of Life Cycle Assessment, 2011Co-Authors: Andrew D. Henderson, Mark A. J. Huijbregts, Thomas E. Mckone, Dik Van De Meent, Michael Z. Hauschild, Henrik Fred Larsen, Manuele Margni, Jerome Payet, Ralph K. Rosenbaum, Olivier JollietAbstract:Purpose The USEtox model was developed in a scientific consensus process involving comparison of and harmonization between existing environmental multimedia fate models. USEtox quantitatively models the continuum from chemical Emission to freshwater ecosystem toxicity via chemical-specific characterization factors (CFs) for Life Cycle Impact Assessment (LCIA). This work provides understanding of the key mechanisms and chemical parameters influencing fate in the environment and impact on aquatic ecosystems. Materials and method USEtox incorporates a matrix framework for multimedia modeling, allowing separation of fate, exposure, and ecotoxicity effects in the determination of an overall CF. Current best practices, such as incorporation of intermittent rain and effect factors (EF) based on substance toxicity across species, are implemented in the model. The USEtox database provides a dataset of over 3,000 organic chemicals, of which approximately 2,500 have freshwater EFs. Freshwater characterization factors for these substances, with a special focus on a subset of chemicals with characteristic properties, were analyzed to understand the contributions of fate, exposure, and effect on the overall CFs. The approach was based on theoretical interpretation of the multimedia model components as well as multidimensional graphical analysis. Results and discussion For direct Emission of a substance to water, the EF strongly controls freshwater ecotoxicity, with a range of up to 10 orders of magnitude. In this release scenario, chemical-specific differences in environmental fate influence the CF for freshwater Emissions by less than 2 orders of magnitude. However, for an Emission to Air or soil, the influence of the fate is more pronounced. Chemical partitioning properties between water, Air, and soil may drive intermedia transfer, which may be limited by the often uncertain, media-specific degradation half-life. Intermedia transfer may be a function of landscape parameters as well; for example, direct transfer from Air to freshwater is limited by the surface area of freshwater. Overall, these altered fate factors may decrease the CF up to 8 orders of magnitude. Conclusions This work brings new clarity to the relative contributions of fate and freshwater ecotoxicity to the calculation of CFs. In concert with the USEtox database, which provides the most extensive compilation of CFs to date, these findings enable those undertaking LCIA to understand and contextualize existing and newly calculated CFs.
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A comparison between the multimedia fate and exposure models caltox and uniform system for evaluation of substances adapted for life-cycle assessment based on the population intake fraction of toxic pollutants
Environmental Toxicology and Chemistry, 2005Co-Authors: Mark A. J. Huijbregts, Loes M.j. Geelen, Edgar G. Hertwich, Thomas E. Mckone, Dik Van De MeentAbstract:In life-cycle assessment (LCA) and comparative risk assessment, potential human exposure to toxic pollutants can be expressed as the population intake fraction (iF), which represents the fraction of the quantity emitted that enters the human population. to assess the influence of model differences in the calculation of the population iF, ingestion and inhalation iFs of 365 substances emitted to Air, freshwater, and soil were calculated with two commonly applied multimedia fate and exposure models, CaltoX and the uniform system for evaluation of substances adapted for life-cycle assessment (USES-LCA). The model comparison showed that differences in the iFs due to model choices were the lowest after Emission to Air and the highest after Emission to soil. Inhalation iFs were more sensitive to model differences compared to ingestion iFs. The choice for a continental seawater compartment, vertical stratification of the soil compartment, rain and no-rain scenarios, and drinking water purification mainly clarify the relevant model differences found in population iFs. Furthermore, pH correction of chemical properties and aerosol-associated deposition on plants appeared to be important for dissociative organics and metals emitted to Air, respectively. Finally, it was found that quantitative structure–activity relationship estimates for superhydrophobics may introduce considerable uncertainty in the calculation of population intake fractions.