Characterization Factors Research Articles

Linking inventories and impact assessment models for addressing biodiversity impacts: mapping rules and challenges

PurposeAn adequate matching between the nomenclature of elementary flows in life cycle inventory (LCI) databases and life cycle impact assessment (LCIA) methods is key for ensuring the proper application of life cycle assessment (LCA). However, the nomenclature of elementary flows lacks harmonization among the LCA community. This paper aims at defining mapping rules and discussing main challenges related to the process of systematically mapping LCI nomenclatures to LCIA methods and models addressing biodiversity impacts.MethodsEight LCIA methods and models addressing biodiversity loss are analyzed: five comprehensive LCIA methods (i.e., LC-IMPACT, Impact World + , Ecological Scarcity 2013, ReCiPe 2016, and Stepwise), one land use intensity-specific LCIA model; and two approaches adapting the GLOBIO model to LCIA. These models and methods are mapped to two LCI nomenclatures (ecoinvent v3.6 as implemented in Simapro and Environmental Footprint (EF) 3.0). A mapping tool was developed to support the process of (a) mapping elementary flows by name, Chemical Service number or available synonyms; (b) implementing specific mapping rules regarding compartment/sub-compartment, and substance name; (c) mapping elementary flows to manually defined proxies (e.g., synonyms, spelling corrections and similar substances); and (d) assigning characterization factors (CFs). The process entails analyzing a case study to identify uncharacterized elementary flows.Results and discussionWe present a mapping of LCIA methods and models addressing impacts on biodiversity loss with specific LCI nomenclatures. Mapping rules are proposed for elementary flows regarding chemicals, carbon emissions, land use, water use, and particulate matter. Specific aspects to be considered in mapping elementary flows in LCIA and LCI nomenclatures are discussed. Main gaps in LCI nomenclatures are associated to toxicity and climate change impacts. The EF 3.0 was more aligned than ecoinvent 3.6 with the LCIA methods and models regarding elementary flows coverage and regionalization level. Analyzing uncharacterized flows revealed further coverage needs for “Chemical, organic” (between 19 and 20% uncharacterized flows), “Chemical, inorganic” (between 9 and 18% uncharacterized flows) and “Chemical, radioactive” (between 9 and 14% uncharacterized flows).ConclusionsThis paper contributes to the operationalization of LCIA methods and models addressing biodiversity impacts by proposing a systematic mapping process and rules for a better LCIA-LCI connection. Different development pathways of LCI (e.g., focused on substance name detail) and LCIA (e.g., towards improved regionalization level) have stretched the gap between both nomenclatures. Recommendations are provided identifying further efforts towards the harmonization of the nomenclature of elementary flows in the LCA community.

Toxicity impacts in the environmental footprint method: calculation principles

PurposeThe EU environmental footprint (EF) is a life cycle assessment (LCA)-based method which aims at assessing the environmental impacts of products and organisations through 16 midpoint impact categories, among which three address toxicity-related impacts. This paper presents the principles underpinning the calculation of the set of characterisation factors (CFs) for the toxicity-related impact categories in the EF version 3.0: freshwater ecotoxicity (ECOTOX), human toxicity cancer (HTOX_c) and human toxicity non-cancer (HTOX_nc).MethodsIn order to respond to the issues that emerged during the EF pilot phase, the input data and the calculation principles of the USEtox® model were updated. In particular, (i) robustness factors (RFs) were introduced to reduce the dominance of metals and to balance the lackness of a robust fate modelling for non-organic compounds in USEtox®; (ii) high-quality data were selected from databases of EU agencies (European Chemicals Agency and European Food Safety Authority) to guarantee the transparency and the reliability of input data; and (iii) a new approach based on HC20 (hazard concentration killing 20% of the exposed population) was implemented to derive freshwater ecotoxicity effect factors (EfF).Results and discussionThe new approach increased the number of characterised chemicals in the three impact categories: ECOTOX (6038 chemicals, + 140%), HTOX_c (1024 chemicals, + 70%) and HTOX_nc (3317 chemicals, + 660%). Moreover, specific derivation principles were defined for assigning CFs also to relevant groups of chemicals (e.g. polycyclic aromatic hydrocarbons), and specific strategies were implemented to better align LCA toxicity data with data used for risk assessment purposes.ConclusionsThe new set of CFs was calculated to ensure a broader coverage of characterised chemicals and to overcome some limitations of the USEtox® model identified during the environmental footprint pilot phase.

Assessing environmental impact of NOX and SO2 emissions in textiles production with chemical footprint

Air pollution is a major concern of the new civilized world due to its adverse impact on human health and environment. As typical air pollutants, nitrogen oxide (NOX) and sulfur dioxide (SO2) not only pollute the atmosphere by forming acid rain and particulate matter, but are also harmful to the human respiratory system. Significant emissions of NOX and SO2 in the production phases make the textile industry under enormous environmental pressure. Chemical footprint (ChF) is an effective method for transforming the potential environmental risks of pollutant emissions into an intuitive form of toxicity. In this study, we present a ChF assessment method for NOX and SO2 emissions from textiles production. For this purpose, we adopt the USEtox model and calculate the relevant characterization factors (CFs) by considering the physicochemical properties and toxicity of NOX and SO2. The textile industry in Zhejiang Province, China, is chosen as a case study to demonstrate the feasibility of this proposed ChF assessment methodology. Results indicate that ChF caused by NOX emission in Zhejiang's textile industry is approximately eight times larger than that caused by SO2 emission. The four sub-sectors of Zhejiang's textile industry (textile manufacturing sector; textile wearing apparel, footware, and caps manufacturing sector; leather, fur, feather and related products manufacturing sector; chemical fibers manufacturing sector) also have similar proportional distributions of ChFs. Besides, the textile manufacturing sector has the largest ChF, accounting for 73% of the total ChF caused by NOX and SO2 emissions.

Development of simplified characterization factors for the assessment of expanded polystyrene and tire wear microplastic emissions applied in a food container life cycle assessment

AbstractTo date, life cycle assessment (LCA) does not include a methodology for assessing the impacts of plastic litter leaked to the environment. This limits the applicability of LCA as a tool to compare the potential impacts of single‐use plastics and their alternatives on ecosystem quality and human health. As a contribution to tackle this issue, this work proposes simplified fate and characterization factors (CFs) for modeling the impacts of two types of microplastics—expanded polystyrene and tire and road wear particles—in the marine environment. In terms of fate mechanisms, this work explores different sedimentation, degradation, and fragmentation rate scenarios, based on literature values and expert estimates. Whereas the fate of expanded polystyrene is sensitive to the different fragmentation, degradation, and sedimentation scenarios, for tire and road wear particles the fate is primarily sensitive to sedimentation. The fate factors are integrated into CFs using an existing exposure and effect factor for microplastics in aquatic environments. Since the CFs of the two studied microplastics show important differences, these results reveal the need for developing polymer‐specific CFs. Finally, the CFs are tested in a case study of on‐the‐go food containers (one single‐use plastic, two compostable alternatives, and one reusable plate). Depending on the fate scenario, plastic litter impacts range from barely noticeable to more than doubling the total potential damage to ecosystem quality, compared to no plastic litter impact assessment. The high uncertainty of the results encourages further research on modeling microplastic fate and impacts in detail.

Methodology to address potential impacts of plastic emissions in life cycle assessment

PurposeProducts made of plastic often appear to have lower environmental impacts than alternatives. However, present life cycle assessments (LCA) do not consider possible risks caused by the emission of plastics into the environment. Following the precautionary principle, we propose characterization factors (CFs) for plastic emissions allowing to calculate impacts of plastic pollution measured in plastic pollution equivalents, based on plastics’ residence time in the environment.Methods and materialsThe method addresses the definition and quantification of plastic emissions in LCA and estimates their fate in the environment based on their persistence. According to our approach, the fate is mainly influenced by the environmental compartment the plastic is initially emitted to, its redistribution to other compartments, and its degradation speed. The latter depends on the polymer type’s specific surface degradation rate (SSDR), the emission’s shape, and its characteristic length. The SSDRs are derived from an extensive literature review. Since the data quality of the SSDR and redistribution rates varies, an uncertainty assessment is carried out based on the pedigree matrix approach. To quantify the fate factor (FF), we calculate the area below the degradation curve of an emission and call it residence time {tau }_{R}.Results and discussionThe results of our research include degradation measurements (SSDRs) retrieved from literature, a surface-driven degradation model, redistribution patterns, FFs based on the residence time, and an uncertainty analysis of the suggested FFs. Depending on the applied time horizon, the values of the FFs range from near zero to values greater than 1000 for different polymer types, size classes, shapes, and initial compartments. Based on the comparison of the compartment-specific FFs with the total compartment-weighted FFs, the polymer types can be grouped into six clusters. The proposed FFs can be used as CFs which can be further developed by integrating the probability of the exposure of humans or organisms to the plastic emission (exposure factor) and for the impacts of plastics on species (effect factor).ConclusionsThe proposed methodology is intended to support (plastic) product designers, for example, regarding materials’ choice, and can serve as a first proxy to estimate potential risks caused by plastic emissions. Besides, the FFs can be used to develop new CFs, which can be linked to one or more existing impact categories, such as human toxicity or ecotoxicity, or new impact categories addressing, for example, potential risks caused by entanglement.

Characterization factors and other air quality impact metrics: Case study for PM2.5-emitting area sources from biofuel feedstock supply

In this paper, we develop a framework and metrics for estimating the impact of emission sources on regulatory compliance and human health for applications in air quality planning and life cycle impact assessment (LCIA). Our framework is based on a pollutant's characterization factor (CF) and three new metrics: Available Regulatory Capacity for Incremental Emissions (ARCIE), Source CF Ratio, and Activity Health Impact (AHI) Ratio. ARCIE can be used to assess whether a receptor location has capacity to accommodate additional source emissions while complying with regulatory limits. We present CF as a midpoint indicator of health impacts per unit mass of emitted pollutant. Source CF Ratio enables comparison of potential new-source locations based on human health impacts. The AHI Ratio estimates the health impacts of a pollutant in relation to the utilization of the source for each unit of product or service. These metrics can be applied to any pollutant, energy source sector (e.g., agriculture, electricity), source type (point, line, area), and spatial modeling domain (nation, state, city, region). We demonstrate these metrics through a case study of fine particulate (PM2.5) emissions from U.S. corn stover harvesting and local processing at various scales, representing steps in the biofuel production process. We model PM2.5 formation in the atmosphere using a novel reduced-complexity chemical transport model called the Intervention Model for Air Pollution (InMAP). Through this case study, we present the first area-source PM2.5 CFs that address the recommendations of several LCIA studies to establish spatially explicit CFs specific to an energy source sector or type. Overall, the framework developed in this work provides multiple new ways to consider the potential impacts of air emissions through spatially differentiated metrics.

On the combination of USEtox® and SimpleBox 4 Nano models for the derivatization of size-dependent characterization factors for engineered nanomaterials

Even if it has been claimed that Life Cycle Assessment is an essential tool to analyze, evaluate, understand and manage the environmental and health impacts of nanotechnology, few studies incorporate characterization factors (CFs) for human toxicity and freshwater ecotoxicity accounting for the impacts of engineered nanomaterials (ENMs) beyond their manufacturing stage. The objective of the present work consisted in identifying the correspondence between the information required and outputs provided by the USEtox® consensus model (which is not nanospecific) and the SimpleBox4Nano model (which accounts for nanospecific processes, e.g. aggregation, attachment and dissolution for Fate Factor derivatization) in order to assess the possibility of integrating the two to derive size-dependent CFs for the varying sizes of ENMs throughout their life cycle. The possibility to combine and integrate the two models appeared to be limited since there is no absolute correspondence between the two of them.

Improving screening model of pesticide risk assessment in surface soils: Addressing regional specific human exposure risks and regulatory management

In this study, a simple screening approach was proposed to evaluate region-specific population health risks of soil pesticides, which was achieved by introducing region-specific factors of pesticides, including fate factors (FFs), environmental distribution factors (DFs), and intake factors (IFs). These region-specific factors were characterized using simple weather variables and calculated the characterization factors (CFs) to link pesticide emissions to population exposure risks. The CF at the reference state indicates the potential of a pesticide entering the human body. Simulations for over 700 pesticides showed that pesticides that are thermodynamically stable in soil organics have large CFs. In addition, we conducted a case study on the region-specific risk assessment of malathion in the United States. The results indicated that colder regions have larger CFs of malathion than those of the warmer regions due to the large FF values for the same emission rates. However, from a regulatory perspective, colder regions should have less strict malathion soil standards than those of warmer regions as children in colder regions spend limited time outdoors. Although other region-specific factors such as soil type and population density need to be considered to improve the model, the approach proposed in this study can be used as a simple screening tool to evaluate region-specific population health risks and manage soil residues for different regions.

167 Impacts on Biodiversity, Environment and Society of Beef Production in the Mexican Tropics: A Life Cycle Assessment Approach

Abstract Beef production exerts strong environmental pressures and can also generate negative social effects. In this study, the impacts on biodiversity, environment and society of beef production in the Mexican tropics, were evaluated through the Life Cycle Assessment (LCA) approach. The functional unit of the study was 1 kg live weight of calf and focused on three productive systems: native silvopastoral (NSP), intensive silvopastoral (ISP) and monoculture (MC). This research was divided into four analysis steps. (1) social impacts; (2) damage to biodiversity; (3) methane emissions and 4) environmental LCA impacts. Using the Social-LCA, we evaluated 18 social indicators, grouped into five categories: human rights, working conditions, health and safety, socio-economic repercussions, and governance. The results showed similarities between the three livestock systems, which revealed a deficient social performance. For projecting the biodiversity damage of pasture land use from an LCA perspective, characterization factors (CFs) were estimated. CFs consist of dimensionless figures representing the potential for damage per unit area of pasture land (potential species loss per m2). The CFs were calculated for three levels of pasture land use intensity (minimal/NSP, light/ISP, intense/MC). Based on the characterization factors developed, the MC showed the least potential species loss. Enteric methane emissions from the production systems were determined using the IPCC Tier 2. The results revealed that the emissions values from enteric methane calculated with Tier 1 overestimated the emissions compared to Tier 2 methodology. LCA indicated a lower environmental impact of the MC on four of the seven categories analyzed, highlighting its lower contribution to climate change and reducing species loss. However, consumption of water and scarcity of fossil fuel resources increased. To achieve tropical sustainable livestock farming, further lines of research should be aimed at evaluating its economic impacts and propose management systems that guarantee better social and environmental performance.

Quantification of the global and regional impacts of gas flaring on human health via spatial differentiation

Globally, gas flaring caused 350 million tonnes of CO2 emissions in 2018. In addition to climate change, this burning practice also has other negative consequences for humans (e.g., respiratory problems) and the environment. The aim of this paper is to quantify the impact of flaring on human health (at the global and country level) via the calculation of the number of disability-adjusted life years (DALYs) caused by the combustion of associated gas. For this quantification, gas flaring emissions were linked with midpoint indicators (e.g., climate change) in life cycle assessment (LCA) for all selected countries. Regionalised characterisation factors (CFs) were applied in the impact assessment to allow for spatial differentiation. The global impact on human health caused by flaring was obtained by taking the sum for all countries. The results show that these flaring emissions globally cause 4.83 × 105 DALYs or 6.19 × 10−5 DALYs/person on an annual basis. This amounts to 0.12% of the total DALYs related to air pollution (from PM2.5) caused by all polluting sectors and 6.51% of the total DALYs related to climate change. To quantify these impacts, this study uses a country perspective rather than considering local characteristics. Thus, if more precise information at a more local level (e.g., city level) is sought, additional factors (e.g., meteorological conditions) should be taken into account. Finally, future research should also focus on the benefits of gas flaring reduction techniques to enable the selection of the most promising technologies for the elimination of gas flaring and its effects.

Global process-based characterization factors of soil carbon depletion for life cycle impact assessment

Regionalization of land use (LU) impact in life cycle assessment (LCA) has gained relevance in recent years. Most regionalized models are statistical, using highly aggregated spatial units and LU classes (e.g. one unique LU class for cropland). Process-based modelling is a powerful characterization tool but so far has never been applied globally for all LU classes. Here, we propose a new set of spatially detailed characterization factors (CFs) for soil organic carbon (SOC) depletion. We used SOC dynamic curves and attainable SOC stocks from a process-based model for more than 17,000 world regions and 81 LU classes. Those classes include 63 agricultural (depending on 4 types of management/production), and 16 forest sub-classes, and 1 grassland and 1 urban class. We matched the CFs to LU elementary flows used by LCA databases at country-level. Results show that CFs are highly dependent on the LU sub-class and management practices. For example, transformation into cropland in general leads to the highest SOC depletion but SOC gains are possible with specific crops.

Improving water scarcity footprint capabilities in arid regions through expansion of characterization factor methods

Water scarcity footprint (WSF) is a recent addition to life cycle assessment methodology that has advanced the understanding of freshwater environmental impact. The Available Water Remaining (AWARE) method is one approach that has gained significant traction in WSF applications. While an effective method for determining WSF, the methodology has limitations that constrain capabilities for determining freshwater environmental impact in arid regions. The primary limitation is the inability to compare regions when more water demand exists than what is available which typically occurs in arid regions. This limitation reduces resolution and therefore decision-making capabilities. This work proposes a novel method for determining WSF in arid regions by capturing and quantifying scarcity when water demand is greater than availability. The approach presented here, called the demand to availability (DTA) method, is intended to be used for small-scale, or subregion analyses in areas where truncation occurs using standard AWARE methods. With the regional specificity, unique characterization factors can be developed to enhance deterministic resolution and ultimately improve decision-making abilities. The DTA methods are presented universally, allowing for application and implementation to any region. A case study was developed to demonstrate the effectiveness of the DTA method by analyzing characterization factors (CFs) and alfalfa WSFs in the arid Southwestern United States. Using the standard AWARE methods, this region originally truncated 38% of counties resulting in zero resolution or decision-making abilities. Results of the case study that used the proposed DTA method show an improved resolution in 100% of these counties, both within CF and alfalfa WSF. Although the proposed method is an improvement for understanding WSFs in arid regions, limitations and constraints still exist and are discussed.

Quantifying uncertainty for AWARE characterization factors

Although it is not yet current practice in life cycle assessment, it is recommended that impact assessment methods be accompanied by their uncertainty data to better guide the decision maker. This work uses the best available information to assess uncertainty of the AWARE model for water scarcity and corresponding sensitivities of input parameters. An uncertainty estimate for the AWARE characterization factors (CFs) is provided via (1) arrays (5000 values per CF) with statistics, (2) dispersion analysis, and (3) distribution best fit and parameters. Results show that uncertainty, represented by the dispersion of the values, varies significantly around the world and tends to be more important in regions of higher scarcity and low in most regions around the world (area based) in terms of absolute spread. Globally, values of 18.8 and 66.28 are found for the spread, represented by the interpercentile range (95%) and interquartile range (25–75%), respectively. The lognormal distribution shows the best fit for most regions around the world and could be used as a default distribution. Two parameters come out as influential: actual water availability (because of precipitation uncertainty) and the global hydrological model itself (because of the variability of results obtained from different models). When compared with uncertainty associated with spatio-temporal variability, uncertainties found in this work are generally lower, and hence improving resolution in water scarcity assessments (to monthly and watershed levels) should remain the priority. Finally, required data for software integration of AWARE uncertainty are provided. This article met the requirements for a Gold-Gold JIE data openness badge described at http://jie.click/badges.

A dynamic approach for life cycle global warming impact assessment of machine tool considering time effect

PurposeMachine tools are the equipment used for the cutting and shaping of materials, like metals, which generate greenhouse gas (GHG) emissions across their life cycles due to material use and energy consumption. The life cycle emissions of machine tools are distributed over time and may vary with technology advancement. This paper aims to incorporate these temporal factors into the global warming impact (GWI) assessment of machine tools and further reveal their influences on the results.MethodIncorporating emission time into the GWI assessment of machine tools is based on the following dynamic life cycle assessment (LCA) framework. First, compute temporally differentiated GHGs of machine tools based on the activity-based modeling. And then, use time-dependent characterization factors (CFs), which are developed based on the radiative forcing concept, to assess their GWI. By using this framework, a dynamic life cycle GWI assessment of machine tool is conducted using two gear hobbing machines. Both the emission time and the potential changes of life cycle emissions due to the improvement of electricity mix and the variation of machine tool use modes are considered.Results and discussionThe results demonstrated that when the emission time was considered, both machines offered 3% of reduction of GWI, compared with their static results, respectively. Further reductions were found for the two machines, when the electricity improvement and the changes of the machine tool use modes were considered. All the differences between the static and the dynamic environmental impact results become smaller with the extension of the time horizons (THs) that accounted for the evaluation.Conclusions and recommendationsThe conventional static LCA has the potential to overestimate the real GWI of machine tools. It is more important to account for the emission time in GWI assessment at shorter THs or for a longer lifetime of machine tools. This work offers a method to dynamically assess the real GWI of machine tools. The proposed method helps to make robust decision-making for environmentally friendly machine tool selection and support sustainable production.

Importance of stopping groundwater irrigation for balancing agriculture and wetland ecosystem

The surge in agricultural water consumption to ensure food security in China has severely hampered the survival of wetland ecosystems. People ignore the importance of “lungs” in the process of meeting the needs for “stomach”. In this study, we quantified the direct and indirect impacts of agricultural water consumption on wetland plant species using Characterization Factors (CFs) and identified their contributions in the three historical periods in the Sanjiang Plain, China. The total potential losses of wetland plant diversity were calculated, and the wetland benefits were evaluated based on the “National Sustainable Agriculture Plan for 2030”. Results indicated that the direct impact of the amount of irrigation water on plant species enhanced, while the indirect impact of groundwater abstraction declined with a drop in one order of magnitude. However, the wetland plant diversity was more responsive to 1 m3 of groundwater abstraction than 1 m3 of irrigation water in all three periods. The agricultural water consumption resulted in more than 120 wetland plant species-eq potential loss from 1987 to 2018, where irrigation water contributed for 57% and groundwater abstraction behavior contributed for 43% loss. The plant diversity loss due to groundwater abstraction was avoidable. By 2030, the wetland plant diversity will be restored by 15.5% according to the national policy, almost all of which comes from the contribution of eliminating the groundwater use. The comprehensive implementation of surface water irrigation, as a practical alternative to groundwater source, is an effective approach to alleviate the contradiction of food security and wetland protection.

Life cycle impact assessment methods for estimating the impacts of dissipative flows of metals

The dissipation of metals leads to potential environmental impacts, usually evaluated for product systems with life cycle assessment. Dissipative flows of metals become inaccessible for future users, going against the common goal of a more circular economy. Therefore, they should be addressed in life cycle impact assessment (LCIA) in the area of protection “Natural Resources.” However, life cycle inventory databases provide limited information on dissipation as they only track emissions to the environment as elementary flows. Therefore, we propose two LCIA methods capturing the expected dissipation patterns of metals after extraction, based on dynamic material flow analysis data. The methods are applied to resource elementary flows in life cycle inventories. The lost potential service time method provides precautionary indications on the lost service due to dissipation over different time horizons. The average dissipation rate method distinguishes between the conservation potentials of different metals. Metals that are relatively well conserved, including major metals such as iron and aluminum, have low characterization factors (CFs). Those with poor process yields, including many companion and high-tech metals such as gallium and tellurium, have high CFs. A comparative study between the developed CFs, along with those of the Abiotic Depletion Potential and Environmental Dissipation Potential methods, show that dissipation trends do not consistently match those of the depletion and environmental dissipation potentials. The proposed methods may thus be complementary to other methods when assessing the impacts of resource use on the area of protection Natural Resources when pursuing an increased material circularity. This article met the requirements for a gold-silver JIE data openness badge at http://jie.click/badges.

Mapping the local impacts of water consumption with regionalized three-dimensional arrays

This study aims to develop a regionalized characterization model of water consumption that can delineate what the potential damage receptors are and where they will be. In order to improve local water resources management, assessment results with more accurate spatial information are needed. This model could be used to derive regionalized life cycle assessment (LCA) results, especially for evaluations within a country. We developed a regionalized characterization model using a watershed-affected matrix and related factors. To construct the watershed-affected matrix, a watershed-affected area (WAA) describing the geographical boundary that will be affected by insufficient water supply from the watershed was proposed as a spatial scale to evaluate the impacts of local water consumption. The model could be performed with input water consumption inventory data carrying watershed scale attributes, and with output damage results carrying local administrative scale attributes. The area of concern (AoC) concept was applied to the model so that water consumption users, such as domestic, agricultural, and industrial sectors, could be used as damage receptor to reveal societal concern about which sector will be influenced due to water depletion. This regionalized characterization model was tested on the three main watersheds in Taiwan, each representing typical, but different, water-usage features. Sector-wise WAAs of each watershed were constructed, and endpoint characterization factors (CFs) of local water consumption were calculated. The visualization results show the damage distribution of water consumption among the damage receptors, which used to be a single average value at the watershed or national scale. The model with the AoC concept is sufficiently flexible for choosing representative affected users and outcome indicators according to stakeholder preferences. Spatial differentiation and comparable results can also support LCA interpretation with detailed information. This model is expected to be further applied to the development of damage prevention strategies.

Creating ecosystem services assessment models incorporating land use impacts based on soil quality

Life cycle assessment (LCA) is a widely applied approach used to evaluate the environmental impacts of a product or service across its life cycle stages; however, the impacts of land use on ecosystem services are less addressed in most LCA studies. This study, therefore, aims to improve the LCA model by incorporating a new impact category of land use on ecosystem services at both midpoint and endpoint levels in the existing ReCiPe2016 impact assessment method. The impacts of land use in the LCA model included land occupation and land transformation. The soil quality-based indicator, soil organic carbon (SOC), was adopted to quantify the soil quality change in ecosystem services caused by land use. A site with contaminated soils was adopted to validate the proposed impact assessment approach and to compare the results of various remediation practices. Our results revealed that the characterization factors (CFs) varied with the type of land use intervention, with land occupation of settlements presenting the highest CFs and land occupation of forest presenting the most negative CFs and thus benefitting ecosystem services. These results were well reflected in the case study, while the type of land intervention was the key factor determining the impact level. The results suggested that long-term occupation, high contamination levels, and high material or energy use contributed to relatively higher impacts of land use on ecosystem services. The proposed approach enables the quantification of land use impacts on ecosystem services as expressed in monetary loss or benefit at the endpoint resource level. The impact assessment results indicated that the in situ bioremediation scenario contributed relatively higher impacts ($12,667 USD) than the excavation and thermal treatment scenario ($−37 USD). These monetary assessment results are informative and are expected to be used in the decision-making process towards achieving beneficial environmental outcomes.

Life cycle assessment applying planetary and regional boundaries to the process level: a model case study

The planetary boundaries framework contains regional boundaries in addition to global boundaries. Geographically resolved methods to assess regional environmental impacts are therefore needed. Existing planetary boundaries-based life cycle assessment (PB-LCA) methods have limited geographical resolution or are not applicable to full product systems, due to high spatial requirements on inventory data. Here, we enable PB-LCA of full product systems across a comprehensive set of regional and global PB impact categories. We propose comparing environmental impacts of individual processes within a product system to assigned shares of regional or global safe operating space (SOS). This is followed by aggregation of process-level results so that accumulated exceedance of assigned SOS is derived across the entire life cycle. We then present a procedure for aggregating geographically resolved characterization factors (CFs) and SOS to country, continent and global levels, ensuring compatibility with typical life cycle inventory results. We then apply the new techniques to a model laundry case study. It involves 61 selected processes, two geographically resolved PB-LCA methods, related to impacts from freshwater use and nitrogen emissions, and a largely spatially generic PB-LCA method that covers a comprehensive set of impact categories. The calculation of accumulated exceedance of assigned SOS may help inform decisions about where in a life cycle to focus impact reduction efforts most urgently. The number of case study processes that exceed their assigned SOS differs when applying the geographically resolved methods, as opposed to the largely spatially generic method. Case study results differ greatly across PB-LCA impact categories, reaffirming the importance of covering a comprehensive set. Geographically resolved methods are needed for all regional impact categories and software support would be advantageous. Existing methods will require periodic updates to reflect ongoing advancements in PB science. Best practice approaches or a consensus for assigning regional SOS to processes are needed. Our study provides a step towards greater operability of geographically resolved PB-LCA methods by enabling application to a full product system within an assessment that covers a comprehensive set of impact categories. The case study application shows potential advantages of the process-level approach and points to the need for quantifying uncertainties in such assessments. Future studies should seek to explore the potential role of PB-LCA in decision support compared with conventional LCA.

La Eutrofización acuática y terrestre como categorías de impacto regional

La creciente conciencia con respecto a la importancia de la protección ambiental y los posibles impactos asociados con los productos han aumentado el interés por el desarrollo de métodos para comprender y tratar los mismos, tal como, el Análisis de Ciclo de Vida (ACV). Uno de los riesgos que deriva de las diversas actividades económicas - agricultura, ganadería, industria, comercio, urbanización, otras- es la eutrofización de cuerpos de agua y del suelo, y estas categorías son consideradas en todos los modelos de Evaluación del Impacto del Ciclo de Vida (EICV). Sin embargo, la Eutrofización acuática (agua dulce y marina) y terrestre aún no está explorada en el ámbito del ACV a nivel país. El plan de Tesis Doctoral tiene como objetivo desarrollar indicadores regionales de Eutrofización, profundizando en el estudio de la degradación del suelo y agua, bajo la metodología del ACV. Hasta el momento, se ha efectuado una revisión exhaustiva de la bibliografía y de antecedentes específicos en el plano nacional e internacional sobre estas categorías de impacto regional. Se observa que hay escasos artículos de investigación que analizan de manera integrada los ecosistemas acuáticos y terrestres, y que en Argentina se requieren estudios sobre Eutrofización en regiones con significancia ambiental, dada la variabilidad bioclimática y el sistema productivo, con factores de caracterización (CFs) dependientes del sitio. Se prevé efectuar un análisis sistemático de los estudios resultantes de la revisión bibliográfica que permitan identificar las necesidades de investigación para la región y aporten una base sólida para la continuidad de los objetivos planteados. La obtención de un conjunto de indicadores contribuiría a la sustentabilidad ambiental de Argentina, brindando herramientas para minimizar los impactos derivados de la producción y el consumo de productos y servicios.