Social aspects for sustainability assessment of technologies—challenges for social life cycle assessment (SLCA)

Purpose

Technologies can contribute to sustainable development (e.g., improving living conditions) and at the same time cause sustainability problems (e.g., emissions). Decisions on alternative technologies should thus ideally be based on the principle to minimize the latter. Analyzing environmental, economic, and social aspects related to technologies supports decisions by identifying the “more sustainable” technology. This paper focuses on social issues. First, it discusses the applicability of the social life cycle assessment (SLCA) guidelines for a comparative technology analysis, taking the example of two case studies in developing countries. Indicating technologies as “sustainable” also means that they are indeed operated over the expected lifetime, which, in development projects, is often not guaranteed. Consequently, social aspects related to implementation conditions should be considered in an SLCA study as well. Thus, a second focus is laid on identifying appropriate indicators to address these aspects.

Methods

First, the SLCA guidelines were examined with regard to applying this product-related approach to two real case studies (analysis of technologies/plants for water supply and for decentralized fuel production) for a comparative technology analysis. Suitable indicators are proposed. To address the second focus, a literature research on technology assessment and implementation in developing countries was conducted. Moreover, socioeconomic studies in the investigation areas of the case studies were consulted. Based on this, indicators addressing implementation conditions were identified from the SLCA guidelines and additional literature.

Results and discussion

The study shows social issues and indicators found in the SLCA guidelines and considered suitable for a comparative technology analysis in the case studies. However, for a sustainability assessment of technologies, especially in developing countries, further indicators are required to address technology implementation conditions. A set of additional social indicators like reported trust in institutions or fluctuation of personnel is proposed. Though these indicators were derived based on specific case studies, they can also be suggested to other technologies and are not necessarily limited to developing countries.

Conclusions

The study pointed out that an application of the SLCA guidelines considering the whole life cycle was not (yet) feasible for the case studies considered. This is mainly due to the lack of data. Regarding technology implementation, it was examined which indicators are available in this SLCA approach and which could additionally be integrated and applied. This is relevant as a potential contribution of technologies to sustainable development can only be achieved when the technologies are successfully implemented.     

An analytic framework for social life cycle impact assessment—part 1: methodology

Purpose

This study aims to develop a new framework of social life cycle impact assessment (SLCIA) method based on the United Nations Environment Program/Society of Environmental Toxicology and Chemistry (UNEP/SETAC) Guidelines for analyzing the social impact in Taiwan, particularly in the electronics industry.

Methods

After reviewing the literature on social life cycle assessment (SLCA), we analyzed existing case studies and developed SLCIA methods based on the UNEP/SETAC Guidelines. We thereafter identified stakeholders, subcategories, and indicators in accordance with the current status of SLCA case studies and opinions from ten experts in the Taiwanese electronics industry. Both quantitative and semi-quantitative indicators were subsequently proposed to assess the social impact of workers in the Taiwanese electronics sector. Each indicator was given the score of 1 to 5 by classifying the social impact percentage of nine scales. To formulate an analytic framework for SLCIA, the weighting values of each subcategory and indicator were determined using the consistent fuzzy preference relations (CFPR) method.

Results and discussion

Seven subcategories and 19 qualitative and quantitative indicators of worker stakeholders for the electronics sector were identified based on the UNEP/SETAC Guidelines. A score of 1 to 5 is assigned to each quantitative indicator by classifying the social impact percentage of nine scales. The data obtained from companies for each quantitative indicator were subsequently transformed into social impact percentage in terms of the statistical data on social situations at the country or industry level. With regard to semi-quantitative indicators, three implementation levels of management efforts on social performance within five elements were identified. The CFPR method was then employed to determine the weights of each indicator by ten experts. Results indicated that preventing forced work practices, protecting children from having to work, and providing minimum and fair wages for workers are the three most important indicators for assessing social impact.

Conclusions

A new SLCIA method that incorporates both quantitative and semi-quantitative indicators was proposed for assessing social impact in the electronics sector in Taiwan. Nine quantitative indicators can be easily organized using available social data from government statistics as performance reference points (PRPs) to determine the social impact exerted by companies. The relative weights were determined to allow for an impact assessment and thus solve the limitation of their currently assumed equal weights. The proposed framework is examined to analyze the social impact of three production sites for semiconductor packaging and manufacturing in Taiwan.

     

A novel social life cycle assessment method for determining workers’ human development: a case study of the sugarcane biorefineries in Brazil

The International Journal of Life Cycle Assessment - The social life cycle assessment (S-LCA) methodology needs to advance in its methodological development, mainly regarding the impact assessment...     

Hotspot identification in the clothing industry using social life cycle assessment—opportunities and challenges of input-output modelling

Purpose

A cradle-to-gate, input/output-based social life cycle assessment (SLCA) was conducted using the Swedish clothing consumption as a case study. The aim was to investigate the influence of the cut-off rule and the definition of “hotspots” in social hotspot assessment. A second aim was to identify social hotspots of Swedish clothing on a national level.

Methods

The case study was based on the SLCA methodology provided in the Guidelines for Social Life Cycle Assessment of Products (Benoît and Mazijn 2009). An input/output model was used to define the product system from cradle to gate. The negative social hotspots were evaluated for a set of social indicators that were selected by consumers. The impact assessment was conducted on a sector and country level by using the Social Hotspots Database. The identified sectors of the economy with high and very high levels of risk were listed for each social indicator.

Results and discussion

The results pinpointed some hotspots throughout the supply chain for Swedish clothing consumption. Some unexpected sectors such as commerce and business services in Bangladesh were identified as important hotspots as well as main sectors in the production phase such as plant fibres, textiles and garments that would be expected also on the bases of a traditional process analysis. A sensitivity analysis on different cut-off values showed the extent to which the choice of cut-off rule can directly affect the results via influence over the number of country-specific sectors (CSSs) in the product system. The influence of the hotspot definition was investigated by evaluating the working hour intensity for low- and medium-risk levels for three different indicators. The results show that for child labour, 92 % of the share of working hours was associated with low- and medium-risk levels. Therefore, the evaluation of risk levels other than high and very high can provide a more complete picture of the hotspots.

Conclusions

The application of input/output-based SLCA on the clothing production supply chain provided a more complete picture of the social hotspots than with traditional process-based SLCA. Some unexpected sectors related to commerce and business appeared as social hotspots in the clothing industry. The study explored some important parameters in applying an input/output-based SLCA. The results show that the cut-off values and definition of hotspots in relation to risk levels can directly influence the results.

     

An analytical framework for social life cycle impact assessment—part 2: case study of labor impacts in an IC packaging company

Purpose

The pressure on brand firms in the electronics industry to improve the labor conditions of their workers in their global production networks is increasing. Given the significance of mitigating the impacts of production on labor, this study used the new development method of social life cycle impact assessment (SLCIA) for conducting labor impact assessment. An illustrative example in an integrated circuit (IC) packaging company is presented to demonstrate the assessment of the impacts and the identification of the potential for improvement of labor practices among three factories.

Methods

SLCIA method was proposed based on the UNEP/SETAC Guidelines that were reviewed in our previous work, Part 1 (in a previous article): Methodology. The proposed method was used to assess the impacts of operations on labor in the three factories of an IC packaging company. Nineteen indicators of labor–stakeholders were used to collect data from factories and organizations in 2012. The obtained values from these three factories were translated into social impact scores that ranged from 1 to 5. The score of each indicator was multiplied by the weights of each indicator, and a final score of labor situations was generated to identify the hotspots of labor impacts and to identify the factory with better labor performance.

Results and discussion

The main goal of this study is to demonstrate the effectiveness of our proposed SLCIA method in assessing the labor impacts in the electronics industry. Among three factories of IC packaging, factory C was ranked as having the lowest social impact on labor with a higher performance, followed by factories B and A. In addition, the results show that four indicators, “lacking labor union,” “did not hire a sufficient number of disabled employees,” “overtime work that exceeded the legal limit,” and “excessive number of dispatched workers,” were recognized as the main social impacts on labor in IC packaging production.

Conclusions

The SLCA technique was used to assess the impacts of the production processes of three IC packaging factories on the labor conditions of their factory workers. The proposed method shed light on the significant impacts of such processes. The proposed model demonstrated its potential advantage by systematically and effectively identifying the labor impact hotspots, which could assist managers in devising strategies that could improve the labor situations within their organizations.

     

Comparative life cycle assessment of car disc brake systems—case study results and method discussion about comparative LCAs

Purpose

Two life cycle assessment (LCA) studies comparing a new low-particulate-matter-emission disc brake and a reference disc brake were presented. The purpose was to identify the difference in potential environmental impacts due to a material change in the new disc brake parts. Additionally, the validity was investigated for the simplification method of omitting identical parts in comparative LCA. This was done by comparing the results between the simplified and the full LCA model.

Methods

The two disc brakes, new disc brake and reference disc brake, were assessed according to the LCA ISO standards. The ReCiPe 2016 Midpoint (hierarchist) impact assessment method was chosen. Simplifying a comparative LCA is possible, all identical parts can be omitted, and only the ones that differ need to be assessed. In this paper, this simplification was called comparative LCA with an omission of identical parts.

Results and discussion

The comparative impacts were analysed over seventeen impact categories. The new disc brake alternative used more resources during the manufacture of one disc compared to the reference disc brake alternative. The shorter life length of the reference disc demanded a higher number of spare part discs to fulfil the same functional unit, but this impact was reduced due to material recycling. The new disc brake impacts were connected primarily to the coating and secondly to the pad manufacture and materials. The validity of the simplification method was investigated by comparing the results of the two LCA models. The impact differences were identical independent of the LCA model, and the same significant impact categories could be identified. Hence, the purpose of the study could be fulfilled, and the simplification was valid.

Conclusions

Both LCA models, simplified and full, revealed that the new disc brake had limited environmental advantages. The omission of identical parts made it more challenging to determine if an impact was significant or insignificant. The simplification seemed to be reasonable.

     

Extending life cycle assessment normalization factors and use of machine learning – A Slovenian case study

Within a life cycle assessment (LCA), normalization is an essential part for interpretation. In Europe, only the European Union normalization factors (EU NFs), with 2000 as the reference year, are available for LCA practitioners, although they work on a regional level. The hypothesis of this research was based on the assumption that some regional NFs deviate from the EU NFs due to unique regional profiles, or because of previously omitted or generalized human impact. In this particular case study set in Slovenia has been tested. By working on the ReCiPe 1.08 life cycle impact assessment methodology, 18 impact categories were investigated, and an additional 3 were added: electromagnetic radiation, light pollution and electric use. To meet practitioners’ needs, the most up-to-date inventory data was used with the reference years of 2007–2012. Out of 440 environmental interventions that were investigated, 139 had no characterization factors (CFs), 97 were estimated using machine learning and 42 had to be omitted. The final result confirmed our hypothesis. Twenty NFs were compared with the EU NFs, and the results have shown that on average, the NFs differ by a factor of 9.76 (median = 1.65). The reasons for the high deviation are due to natural land transformation, and ionising radiation, toxicological and ecotoxicological impact categories; where there are major data gaps in the CFs. The primary concern of the research was data availability for toxicological and ecotoxicological parameters for toxicity-related emissions, and the fact that original CFs covered only 50.25% of plant protection products used in Slovenia. Toxicological and ecotoxicological uncertainties were illustrated by comparing four different results. Future studies should be focused on the use of machine learning to provide the next generation of CFs and to go beyond the CFs’ damage-oriented assessment. Remediation should be the new endpoint category and its units should be Joules.     

Capability of social life cycle assessment for analyzing the artisanal small-scale gold mining sector—case study in the Amazonian rainforest in Brazil

The International Journal of Life Cycle Assessment - Gold extraction in the Amazonian rainforest is accompanied by ecological threats and social grievances, but at the same time, the artisanal...     

A GIS based method to calculate regionalized land use characterization factors for life cycle impact assessment using LANCA®

The International Journal of Life Cycle Assessment - Land is used and modified in its natural function for the cultivation of food and energy crops, for infrastructure and other production...     

Psychosocial risk factors’ impact pathway for social life cycle assessment: an application to citrus life cycles in South Italy

The International Journal of Life Cycle Assessment - Social life cycle assessment (SLCA) was the last tool to be developed within the framework of life cycle thinking, and since the beginning,...     

Life cycle inventory and impact assessment for an asphalt pavement road construction—a case study in Brazil

The International Journal of Life Cycle Assessment - Currently, there are no life cycle impact data available on the construction of road infrastructure in Brazil. This study aimed to determine...     

“Less is better” and “only above threshold”: Two incompatible paradigms for human toxicity in life cycle assessment?

The absence of spatial and temporal information in the data from a typical Life Cycle Inventory puts constraints on the possibilities of subsequent Life Cycle Impact Assessment to predict actual impact. Usual methods for Life Cycle Impact Assessment (often referred to as “less is better” methods) make only limited use of spatial and temporal information, because they predict concentration increases rather than full concentrations. As a consequence it does not seem possible to evaluate whether a threshold value is surpassed. The resulting poor accordance between the predicted impact and the expected occurrence of actual impact is a major problem. This problem is particularly relevant for human toxicity assessment, since the probability of surpassing thresholds here traditionally is the main point of attention. A considerable group of practitioners suggests to follow an “only above threshold” principle by introduction of assessment tools from risk assessment and environmental impact assessment in LCA. Intensive debate is going on about possibilities and limitations of “less is better” and “only above threshold”. The debate is obscured by two underlying discussions (about no-effect-levels and about data-availability) that are partly, but not fully intertwined. Both principles tend to be given fixed positions in these discussions, and are therefore often put forward as fundamentally different and incompatible with each other. This article entwines the discussions, shows parallels between both principles, and uses these parallels to present a new method for Life Cycle Impact Assessment of human toxicity from air emissions that — with limited data requirement from Life Cycle Inventory — can take as well threshold evaluation and spatial source-differentiation into account.     

Integrating triple bottom line input–output analysis into life cycle sustainability assessment framework: the case for US buildings

Purpose

With the increasing concerns related to integration of social and economic dimensions of the sustainability into life cycle assessment (LCA), traditional LCA approach has been transformed into a new concept, which is called as life cycle sustainability assessment (LCSA). This study aims to contribute the existing LCSA framework by integrating several social and economic indicators to demonstrate the usefulness of input–output modeling on quantifying sustainability impacts. Additionally, inclusion of all indirect supply chain-related impacts provides an economy-wide analysis and a macro-level LCSA. Current research also aims to identify and outline economic, social, and environmental impacts, termed as triple bottom line (TBL), of the US residential and commercial buildings encompassing building construction, operation, and disposal phases.

Methods

To achieve this goal, TBL economic input–output based hybrid LCA model is utilized for assessing building sustainability of the US residential and commercial buildings. Residential buildings include single and multi-family structures, while medical buildings, hospitals, special care buildings, office buildings, including financial buildings, multi-merchandise shopping, beverage and food establishments, warehouses, and other commercial structures are classified as commercial buildings according to the US Department of Commerce. In this analysis, 16 macro-level sustainability assessment indicators were chosen and divided into three main categories, namely environmental, social, and economic indicators.

Results and discussion

Analysis results revealed that construction phase, electricity use, and commuting played a crucial role in much of the sustainability impact categories. The electricity use was the most dominant component of the environmental impacts with more than 50 % of greenhouse gas emissions and energy consumption through all life cycle stages of the US buildings. In addition, construction phase has the largest share in income category with 60 % of the total income generated through residential building’s life cycle. Residential buildings have higher shares in all of the sustainability impact categories due to their relatively higher economic activity and different supply chain characteristics.

Conclusions

This paper is an important attempt toward integrating the TBL perspective into LCSA framework. Policymakers can benefit from such approach and quantify macro-level environmental, economic, and social impacts of their policy implications simultaneously. Another important outcome of this study is that focusing only environmental impacts may misguide decision-makers and compromise social and economic benefits while trying to reduce environmental impacts. Hence, instead of focusing on environmental impacts only, this study filled the gap about analyzing sustainability impacts of buildings from a holistic perspective.     

IMPACT 2002+, ReCiPe 2008 and ILCD’s recommended practice for characterization modelling in life cycle impact assessment: a case study-based comparison

Purpose

The European Commission has launched a recommended set of characterization models and factors for application in life cycle impact assessment (LCIA). However, it is not known how this recommended practice, referred to as the ILCD 2009, performs relative to some of the most frequently used alternative LCIA methodologies. Here, we compare the ILCD 2009 with IMPACT 2002+ and ReCiPe 2008, focusing on characterization at midpoint based on a case study comparing four window design options for use in a residential building.

Methods

Ranking of the four window options was done for each impact category within each methodology. To allow comparison across the methodologies both in terms of total impact scores and contribution patterns for individual substances, impact scores were converted into common metrics for each impact category.

Results and discussion

Apart from toxic impacts on human health and ecosystems, all studied methodologies consistently identify the same window option as having the lowest and the highest environmental impact. This is mainly because few processes, associated with production of heat, dominate the total impacts, and there is a large difference in demand for heat between the compared options. Despite this general agreement in ranking, differences in impact scores are above 3 orders of magnitude for human health impacts from ionizing radiation and ecosystem impacts from land use, and they lie between 1 and 3 orders of magnitude for metal depletion and for toxicity-related impact categories. The differences are somewhat smaller (within 1 order of magnitude) for the impact categories respiratory inorganics and photochemical ozone formation, and are within a factor of 3 for the remaining impact categories. The differences in impact scores in our case study are brought about by the differences in underlying characterization models and/or substance coverage, depending on the impact category.

Conclusions

In spite of substantial differences in impact scores for the individual impact categories, we find that the studied LCIA methods point to the same conclusion with respect to identifying the alternative with the lowest environmental burden and ascribe this to the fact that few processes are driving the main environmental impacts, and there is large difference in demand for output from these processes between the compared options. Even though the overall conclusions remain the same for our case study, the choice of the ILCD’s recommended practice over the existing alternatives does matter for the impact categories ionizing radiation and land use and all toxicity-related impact categories.     

USEtox—the UNEP-SETAC toxicity model: recommended characterisation factors for human toxicity and freshwater ecotoxicity in life cycle impact assessment

Background, aim and scope  In 2005, a comprehensive comparison of life cycle impact assessment toxicity characterisation models was initiated by the United Nations Environment Program (UNEP)–Society for Environmental Toxicology and Chemistry (SETAC) Life Cycle Initiative, directly involving the model developers of CalTOX, IMPACT 2002, USES-LCA, BETR, EDIP, WATSON and EcoSense. In this paper, we describe this model comparison process and its results—in particular the scientific consensus model developed by the model developers. The main objectives of this effort were (1) to identify specific sources of differences between the models’ results and structure, (2) to detect the indispensable model components and (3) to build a scientific consensus model from them, representing recommended practice. Materials and methods  A chemical test set of 45 organics covering a wide range of property combinations was selected for this purpose. All models used this set. In three workshops, the model comparison participants identified key fate, exposure and effect issues via comparison of the final characterisation factors and selected intermediate outputs for fate, human exposure and toxic effects for the test set applied to all models. Results  Through this process, we were able to reduce inter-model variation from an initial range of up to 13 orders of magnitude down to no more than two orders of magnitude for any substance. This led to the development of USEtox, a scientific consensus model that contains only the most influential model elements. These were, for example, process formulations accounting for intermittent rain, defining a closed or open system environment or nesting an urban box in a continental box. Discussion  The precision of the new characterisation factors (CFs) is within a factor of 100–1,000 for human health and 10–100 for freshwater ecotoxicity of all other models compared to 12 orders of magnitude variation between the CFs of each model, respectively. The achieved reduction of inter-model variability by up to 11 orders of magnitude is a significant improvement. Conclusions  USEtox provides a parsimonious and transparent tool for human health and ecosystem CF estimates. Based on a referenced database, it has now been used to calculate CFs for several thousand substances and forms the basis of the recommendations from UNEP-SETAC’s Life Cycle Initiative regarding characterisation of toxic impacts in life cycle assessment. Recommendations and perspectives  We provide both recommended and interim (not recommended and to be used with caution) characterisation factors for human health and freshwater ecotoxicity impacts. After a process of consensus building among stakeholders on a broad scale as well as several improvements regarding a wider and easier applicability of the model, USEtox will become available to practitioners for the calculation of further CFs. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.

Mineral resources in life cycle impact assessment: part II – recommendations on application-dependent use of existing methods and on future method development needs

The International Journal of Life Cycle Assessment - Assessing impacts of abiotic resource use has been a topic of persistent debate among life cycle impact assessment (LCIA) method developers and...