Statistical analysis of use-phase energy consumption of textile products

Purpose

The purpose of this work was to present a methodology to assess the energy consumption, specifically the energy utilized in the washing and drying processes, of textile products in their use-phase with the help of statistical tools. Regardless of the environmental impacts associated with the use-phase of textile products, analysis of energy consumption in that phase is still lacking. There is a need to design methodology for identifying the hotspots and parameters influencing the energy consumption in the use-phase of textile products. A pragmatic method that consists of a life-cycle assessment (LCA) framework plus principle component analysis (PCA), extended by Procrustes analysis (PA), is used to determine the energy consumption and minimize the possible uncertainties in the use-phase of textile product systems.

Methods

The LCA plus PCA-PA method employed in this work to analyze the energy consumption of textile products in the use-phase comprises two statistical tools. First, PCA was applied to find the key parameters affecting the results. As an extension of PCA, PA was performed to highlight the most prominent variables within the dataset and extract the maximum amount of information. Lastly, hierarchical cluster analysis (HCA) was utilized for the classification of textile products on the basis of energy consumption variables and the similarity of their results.

Results and discussion

Among various energy consuming parameters in the use-phase of a textile product, both geographical and physical aspects can be prominent variables that significantly can affect the results of the energy consumption. After the LCA plus PCA-PA methodology, country of the use-phase in the geographical aspect and in the physical aspect, the fiber type and weight of the products were the influential variables. Hotspots or influential parameters being identified, a number of steps can be taken that can play an important role in decreasing environmental impacts by reducing the energy consumption in the laundering process of textile products during the use-phase.

Conclusions

The methodology of LCA plus PCA-PA for energy consumption in textile products was employed to study the gap in currently available assessments. Using this method, the main influencing energy consuming parameters or hotspots in the use-phase of a textile product system could easily be identified and potential improvements of sustainability can be proposed.

     

On the boundary between economy and environment in life cycle assessment

Purpose

We investigate how the boundary between product systems and their environment has been delineated in life cycle assessment and question the usefulness and ontological relevance of a strict division between the two.

Methods

We consider flows, activities and impacts as general terms applicable to both product systems and their environment and propose that the ontologically relevant boundary is between the flows that are modelled as inputs to other activities (economic or environmental)—and the flows that—in a specific study—are regarded as final impacts, in the sense that no further feedback into the product system is considered before these impacts are applied in decision-making. Using this conceptual model, we contrast the traditional mathematical calculation of the life cycle impacts with a new, simpler computational structure where the life cycle impacts are calculated directly as part of the Leontief inverse, treating product flows and environmental flows in parallel, without the need to consider any boundary between economic and environmental activities.

Results and discussion

Our theoretical outline and the numerical example demonstrate that the distinctions and boundaries between product systems and their environment are unnecessary and in some cases obstructive from the perspective of impact assessment, and can therefore be ignored or chosen freely to reflect meaningful distinctions of specific life cycle assessment (LCA) studies. We show that our proposed computational structure is backwards compatible with the current practice of LCA modelling, while allowing inclusion of feedback loops both from the environment to the economy and internally between different impact categories in the impact assessment.

Conclusions

Our proposed computational structure for LCA facilitates consistent, explicit and transparent modelling of the feedback loops between environment and the economy and between different environmental mechanisms. The explicit and transparent modelling, combining economic and environmental information in a common computational structure, facilitates data exchange and re-use between different academic fields.

     

Integration of Functional and Environmental Performance Design Decisions: A Mechanical Component Case Study

Product design-for-environment (DfE) has traditionally relied on life-cycle assessment (LCA) as a primary means of assessing environmental performance. To date, LCA has focused on static inventory and impacts of material streams during the stages of resource extraction, component manufacture, product use, and end of life at a high level of aggregation. Improvement analysis, though theoretically an important stage of LCA, is practically very challenging to implement using LCA alone. One reason for this is that the focus on detailed characterization of material streams does not facilitate a development of an understanding of the mechanistic relationship between design intent and material, manufacturing, and use-phase potential impacts. As the product development community transitions from sequential design to more streamlined concurrent design, interactive design tools are needed as a supplement to assessment tools in order to facilitate tradeoffs among environmental and other factors. This article presents an environmental analysis approach based on detailed process modeling which evaluates components from a functional design point of view. From a manufacturer's perspective, local potential effects in aggregate are often as important as global potential impacts. Furthermore, impacts often relate to explicit trade-offs between different life-cycle stages, such as production and use. In this article, the influence of functional design and manufacturing specifications (surface tolerance and finish) on localized potential impacts is illustrated through two different mechanical component (steel roller bearing and rotating shaft) case studies. Detailed analytical tools are key in enabling optimization and trade-offs by designers and process planners. The functional modeling approach is an important complement to LCA in providing a well-defined view of environmental performance.     

Rethinking a product and its function using LCA—experiences of New Zealand manufacturing companies

Purpose

It has been recognised that life cycle assessment (LCA) has a role in framing problem situations in environmental management. Yet relatively few studies have investigated whether the use of LCA does actually lead to the reconceptualisation of product systems as opposed to answering predefined questions. This paper discusses the experiences of six manufacturing firms that commissioned LCA studies as part of a life cycle management project managed by Landcare Research in New Zealand.

Methods

The initial goal and scope of the study was developed by each company’s representative in a workshop that was organised as part of the LCM project. The scope for three of the studies was subsequently redefined by the LCA specialists at Landcare Research and agreed with senior managers at the company. The LCA specialists undertook the LCA studies and presented the results to the companies.

Results and discussion

A significant reconceptualisation of the product system took place in three of the six LCA studies. This reconceptualisation would not have taken place if the scope of the LCA studies had been restricted to address the questions originally asked by the companies. The three companies showed some resistance to expanding the scope.

Conclusions

Use of LCA can lead to reconceptualisation of product systems by companies and quite different priorities for improvement options. Initial resistance to expanding a study’s scope may be (partially) overcome by data collection activities and informal discussions between the LCA specialist and company staff during the process of undertaking the LCA study.     

Life cycle assessment of emerging environmental technologies in the early stage of development: A case study on nanostructured materials

The use of nanostructured materials has been recently proposed in the field of environmental nanoremediation. This approach consists in using nanomaterials not directly, but as building blocks for the design of nano‐porous micro‐dimensional systems, overcoming the eco‐ and health‐toxicology risks generally associated with the use of nano‐sized technologies. Herein we report the use of life cycle assessment (LCA) as an eco‐design tool for optimizing the production of cellulose nanosponges (CNS), nanostructured materials recently developed for water remediation purposes. LCA was applied from the acquisition of raw materials to the synthesis of CNS (from cradle‐to‐gate), considering three production systems, from the lab‐level to a modeled scale‐up system. The lab‐scale LCA identified the main environmental hotspots, namely the energy‐consuming steps and the final purification of the material (washing step). In a second lab‐scale production, an improvement action could be implemented, switching the washing solvent from methanol to water and decreasing the washing temperature. A second LCA showed a reduced contribution to the impacts from the materials, while the global impacts remained within the same order of magnitude. A simulated scale‐up of the process allowed to optimize the energy‐consuming steps and the water consumption, through internal recycling. A third LCA assessed the resulting benefits and a decrease in the global impacts by two orders of magnitude. Our study contributes to the discussion of LCA community, providing a focus on the importance of scaling‐up of emerging technologies, namely nanostructured porous materials, highlighting the benefits of a LCA based approach since the very beginning of product design (eco‐design).     

Does the Production of an Airbag Injure more People than the Airbag Saves in Traffic?

Social life cycle assessment (S‐LCA) has been discussed for some years in the LCA community. We raise two points of criticism against current S‐LCA approaches. First, the development of S‐LCA methodology has not, to date, been based on experience with actual case studies. Second, for social impacts to be meaningfully assessed in a life cycle perspective, social indicators need to be unambiguously interpreted in all social contexts along the life cycle. We here discuss an empirically based approach to S‐LCA, illustrated by a case study of an automobile airbag system. The aim of the case study is to compare the injuries and lives lost during the product life cycle of the airbag system (excluding waste handling impacts) with the injuries prevented and lives saved during its use. The indicator used for assessing social impacts in this study is disability‐adjusted life years (DALY). The results from this study indicate that the purpose of an airbag system, which is to save lives and prevent injuries, is justified also in a life cycle perspective.     

Environmental Impacts of Products: A Detailed Review of Studies

Environmental effects of economic activities are ultimately driven by consumption, via impacts of the production, use, and waste management phases of products and services ultimately consumed. Integrated product policy (IPP) addressing the life‐cycle impacts of products forms an innovative new generation of environmental policy. Yet this policy requires insight into the final consumption expenditures and related products that have the greatest life‐cycle environmental impacts. This review article brings together the conclusions of 11 studies that analyze the life‐cycle impacts of total societal consumption and the relative importance of different final consumption categories. This review addresses in general studies that were included in the project Environmental Impacts of Products (EIPRO) of the European Union (EU), which form the basis of this special issue. Unlike most studies done in the past 25 years on similar topics, the studies reviewed here covered a broad set of environmental impacts beyond just energy use or carbon dioxide (CO₂) emissions. The studies differed greatly in basic approach (extrapolating LCA data to impacts of consumption categories versus approaches based on environmentally extended input‐output (EEIO) tables), geographical region, disaggregation of final demand, data inventory used, and method of impact assessment. Nevertheless, across all studies a limited number of priorities emerged. The three main priorities, housing, transport, and food, are responsible for 70% of the environmental impacts in most categories, although covering only 55% of the final expenditure in the 25 countries that currently make up the EU. At a more detailed level, priorities are car and most probably air travel within transport, meat and dairy within food, and building structures, heating, and (electrical) energy‐using products within housing. Expenditures on clothing, communication, health care, and education are considerably less important. Given the very different approaches followed in each of the sources reviewed, this result hence must be regarded as extremely robust. Recommendations are given to harmonize and improve the methodological approaches of such analyses, for instance, with regard to modeling of imports, inclusion of capital goods, and making an explicit distinction between household and government expenditure.     

Designing the ideal green product: Lca/SCLA in reverse

Traditional life-cycle assessment begins with a product and examines its environmental impacts throughout its life cycle. An alternative approach is to proceed in reverse: to examine the need that the product is designed to fulfill, to determine the minimal environmental impacts that could be engendered by filling that need, and thereby to design the “ideal green product” for the purpose. This approach, termed reverse life-cycle assessment (RLCA), is demonstrated by examining the environmental impacts attributable to a generic washing machine of current design, and then by reviewing other ways in which the provisioning of clean clothing may be accomplished. RLCA, as used here, is shown to encourage systems thinking and to identify opportunities for innovation in design and in marketing of environmentally-responsible products in ways that would be unlikely to arise from a traditional LCA.     

Life cycle assessment evaluation of green product labeling systems for residential construction

Purpose

Life cycle assessment (LCA) is a tool that can be utilized to holistically evaluate novel trends in the construction industry and the associated environmental impacts. Green labels are awarded by several organizations based on single or multiple attributes. The use of multi-criteria labels is a good start to the labeling process as opposed to single criteria labels that ignore a majority of impacts from products. Life cycle thinking, in theory, has the potential to improve the environmental impacts of labeling systems. However, LCA databases currently are lacking in detailed information about products or sometimes provide conflicting information.

Method

This study compares generic and green-labeled carpets, paints, and linoleum flooring using the Building for Environmental and Economic Sustainability (BEES) LCA database. The results from these comparisons are not intuitive and are contradictory in several impact categories with respect to the greenness of the product. Other data sources such as environmental product declarations and ecoinvent are also compared with the BEES data to compare the results and display the disparity in the databases.

Results

This study shows that partial LCAs focused on the production and transportation phase help in identifying improvements in the product itself and improving the manufacturing process but the results are uncertain and dependent upon the source or database. Inconsistencies in the data and missing categories add to the ambiguity in LCA results.

Conclusions

While life cycle thinking in concept can improve the green labeling systems available, LCA data is lacking. Therefore, LCA data and tools need to improve to support and enable market trends.     

Implicit prioritization in life cycle assessment: text mining and detecting metapatterns in the literature

Purpose

Life cycle assessment aims to evaluate multiple kinds of environmental impact associated with a product or process across its life cycle. Objective evaluation is a common goal, though the community recognizes that implicit valuations of diverse impacts resulting from analytical choices and choice of subject matter are present. This research evaluates whether these implicit valuations lead to detectable priority shifts in the published English language academic LCA literature over time.

Methods

A near-comprehensive investigation of the LCA literature is undertaken by applying a text mining technique known as topic modeling to over 8200 environment-related LCA journal article titles and abstracts published between 1995 and 2014.

Results and discussion

Topic modeling using MALLET software and manual validation shows that over time, the LCA literature reflects a dramatic proportional increase in attention to climate change and a corresponding decline in attention to human and ecosystem health impacts, accentuated by rapid growth of the LCA literature. This result indicates an implicit prioritization of climate over other impact categories, a field-scale trend that appears to originate mostly in the broader environmental community rather than the LCA methodological community. Reasons for proportionally increasing publication of climate-related LCA might include the relative robustness of greenhouse gas emissions as an environmental impact indicator, a correlation with funding priorities, researcher interest in supporting active policy debates, or a revealed priority on climate versus other environmental impacts in the scholarly community.

Conclusions

As LCA becomes more widespread, recognizing and addressing the fact that analyses are not objective becomes correspondingly more important. Given the emergence of implicit prioritizations in the LCA literature, such as the impact prioritization of climate identified here with the use of computational tools, this work recommends the development and use of techniques that make impact prioritization explicit and enable consistent analysis of result sensitivity to value judgments. Explicit prioritization can improve transparency while enabling more systematic investigation of the effects of value choices on how LCA results are used.

     

A system boundary identification method for life cycle assessment

Purpose

Life cycle assessment (LCA) is a useful tool for quantifying the overall environmental impacts of a product, process, or service. The scientific scope and boundary definition are important to ensure the accuracy of LCA results. Defining the boundary in LCA is difficult and there are no commonly accepted scientific methods yet. The objective of this research is to present a comprehensive discussion of system boundaries in LCA and to develop an appropriate boundary delimitation method.

Methods

A product system is partitioned into the primary system and interrelated subsystems. The hierarchical relationship of flow and process is clarified by introducing flow- and process-related interventions. A system boundary curve model of the LCA is developed and the threshold rules for judging whether the system boundary satisfies the research requirement are proposed. Quantitative criteria from environmental, technical, geographical and temporal dimensions are presented to limit the boundaries of LCA. An algorithm is developed to identify an appropriate boundary by searching the process tree and evaluating the environmental impact contribution of each process while it is added into the studied system.

Results and discussion

The difference between a limited system and a theoretically complete system is presented. A case study is conducted on a color TV set to demonstrate and validate the method of boundary identification. The results showed that the overall environmental impact indicator exhibits a slow growth after a certain number of processes considered, and the gradient of the fitting curve trends to zero gradually. According to the threshold rules, a relatively accurate system boundary could be obtained.

Conclusions

It is found from this research that the system boundary curve describes the growth of life cycle impact assessment (LCIA) results as processes are added. The two threshold rules and identification methods presented can be used to identify system boundary of LCA. The case study demonstrated that the methodology presented in this paper is an effective tool for the boundary identification.     

Ecosystem Services in Life Cycle Assessment while Encouraging Techno‐Ecological Synergies

Life cycle assessment (LCA) has enabled consideration of environmental impacts beyond the narrow boundary of traditional engineering methods. This reduces the chance of shifting impacts outside the system boundary. However, sustainability also requires that supporting ecosystems are not adversely affected and remain capable of providing goods and services for supporting human activities. Conventional LCA does not account for this role of nature, and its metrics are best for comparing alternatives. These relative metrics do not provide information about absolute environmental sustainability, which requires comparison between the demand and supply of ecosystem services (ES). Techno‐ecological synergy (TES) is a framework to account for ES, and has been demonstrated by application to systems such as buildings and manufacturing activities that have narrow system boundaries. This article develops an approach for techno‐ecological synergy in life cycle assessment (TES‐LCA) by expanding the steps in conventional LCA to incorporate the demand and supply of ecosystem goods and services at multiple spatial scales. This enables calculation of absolute environmental sustainability metrics, and helps identify opportunities for improving a life cycle not just by reducing impacts, but also by restoring and protecting ecosystems. TES‐LCA of a biofuel life cycle demonstrates this approach by considering the ES of carbon sequestration, air quality regulation, and water provisioning. Results show that for the carbon sequestration ecosystem service, farming can be locally sustainable but unsustainable at the global or serviceshed scale. Air quality regulation is unsustainable at all scales, while water provisioning is sustainable at all scales for this study in the eastern part of the United States.     

Challenges of organizational LCA: lessons learned from road testing the guidance on organizational life cycle assessment

Purpose

The novelty of the O-LCA method and the existing differences with the established product LCA practice, as well as the unique structure each organization, pose a broad range of methodological and application challenges, in addition to the general methodological gaps in LCA. In order to provide practitioners with lessons learned for future applications and boost future method development efforts, the paper discusses those challenges.

Methods

The challenges included in this paper were mainly identified from a survey administered to the road testers and from experiences during the piloting process. These are complemented with case studies from literature. The focus of the paper is on challenges exclusive to the organizational approach, although some additional issues common to product LCA but intensified in organizational LCA are also included. Each issue is characterized and exemplified, recommendations of reference standards are analyzed, and possible solutions discussed.

Results and discussion

With the goal and scope of O-LCA, some challenging issues were to select part of an organization as the reporting organization, and the operability of the reporting flow. Regarding the system boundary, the challenges were which parts of the supply chain should be included in the study, problems when setting the system boundary for the service sector, how to include supporting activities, and how to prepare the right system boundary diagrams. Regarding the inventory stage, the discussion starts with alternatives to the categorization of the inventory into activities and the aggregation of those activities into groups. It includes an equivalence table for an easier transfer from other organizational frameworks (ISO 14069 and the GHG Protocol). Some challenges during impact assessment and interpretation were the assessment of local impacts, scoping performance tracking, and the use of O-LCA results for an organization’s strategy.

Conclusions

The review of challenges is not meant as a complete overview of all possible challenges—new challenges may arise in future case studies. Further application testing is needed, along with research to support a future revision of the O-LCA Guidance, in line with the issues highlighted in this paper and new challenges may arise in future case studies. O-LCA has the potential to contribute in the future implementation of the life cycle concept in environmental management systems, in the development of organizational footprint metrics for region-specific impacts, and in the social dimension of life cycle assessment.

     

Assessing potential desertification environmental impact in life cycle assessment

Background, aim and scope  

Life cycle assessment (LCA) enables the objective assessment of global environmental burdens associated with the life cycle of a product or a production system. One of the main weaknesses of LCA is that, as yet, there is no scientific agreement on the assessment methods for land-use related impacts, which results in either the exclusion or the lack of assessment of local environmental impacts related to land use. The inclusion of the desertification impact in LCA studies of any human activity can be important in high-desertification risk regions.     

Characterizing,Propagating, and Analyzing Uncertainty in Life‐Cycle Assessment: A Survey of Quantitative Approaches

Life‐cycle assessment (LCA) practitioners build models to quantify resource consumption, environmental releases, and potential environmental and human health impacts of product systems. Most often, practitioners define a model structure, assign a single value to each parameter, and build deterministic models to approximate environmental outcomes. This approach fails to capture the variability and uncertainty inherent in LCA. To make good decisions, decision makers need to understand the uncertainty in and divergence between LCA outcomes for different product systems. Several approaches for conducting LCA under uncertainty have been proposed and implemented. For example, Monte Carlo simulation and fuzzy set theory have been applied in a limited number of LCA studies. These approaches are well understood and are generally accepted in quantitative decision analysis. But they do not guarantee reliable outcomes. A survey of approaches used to incorporate quantitative uncertainty analysis into LCA is presented. The suitability of each approach for providing reliable outcomes and enabling better decisions is discussed. Approaches that may lead to overconfident or unreliable results are discussed and guidance for improving uncertainty analysis in LCA is provided.     

Partial modelling of the perennial crop cycle misleads LCA results in two contrasted case studies

Purpose

As highlighted in recent reviews, there is a need to harmonise the way life cycle assessment (LCA) of perennial crops is conducted. In most published LCA on perennial crops, the modelling of the agricultural production is based on data sets for just one productive year. This may be misleading since performance and impacts of the system may greatly vary year by year. The purposes of this study are to analyse how partial modelling of the perennial cycle through non-holistic data collection may affect LCA results and to make recommendations.

Methods

Three modelling choices for the perennial crop cycle were tested in parallel in two contrasted LCA case studies: oil palm fruits from Indonesia, and small citrus from Morocco. Modelling choices tested were as follows: (i) a chronological modelling over the complete crop cycle of orchards, (ii) a 3-year average from the productive phase, and (iii) various single years from the productive phase. In both case studies, the system boundary was a cradle-to-farm gate with a functional unit of 1 kg fresh fruits. LCA midpoint impacts were calculated with ReCiPe 2008 in Simapro©V.7. We first analysed how inputs, yields and potential impacts varied over time. We then analysed process contributions in the baseline model, i.e. the chronological modelling, and finally compared LCA results for the various perennial modelling choices.

Results and discussion

Agricultural practices, yields and impacts varied over the years especially during the first 3–9 years depending on the case study. In both case studies, the modelling choices to account or not for the whole perennial cycle drastically influenced LCA results. The differences could be explained by the inclusion or not of the yearly variability and the accounting or not of the immature phase, which contributed to 7–40 or 6.5–29 % of all impact categories for oil palm fruit and citrus, respectively.

Conclusions

The chosen approach to model the perennial cycle influenced the final LCA results for two contrasted case studies and deserved specific attention. Although data availability may remain the limiting factor in most cases, assumptions can be made to interpolate or extrapolate some data sets or to consolidate data sets from chronosequences (i.e. modular modelling). In all cases, we suggest that the approach chosen to model the perennial cycle and the representativeness of associated collected data should be made transparent and discussed. Further research work is needed to improve the understanding and modelling of perennial crop functioning and LCA assessment.

     

Designing hybrid life cycle assessment models based on uncertainty and complexity

Purpose

Despite the wide use of LCA for environmental profiling, the approach for determining the system boundary within LCA models continues to be subjective and lacking in mathematical rigor. As a result, life cycle models are often developed in an ad hoc manner, and are difficult to compare. Significant environmental impacts may be inadvertently left out. Overcoming this shortcoming can help elicit greater confidence in life cycle models and their use for decision making.

Methods

This paper describes a framework for hybrid life cycle model generation by selecting activities based on their importance, parametric uncertainty, and contribution to network complexity. The importance of activities is determined by structural path analysis—which then guides the construction of life cycle models based on uncertainty and complexity indicators. Information about uncertainty is from the available life cycle inventory; complexity is quantified by cost or granularity. The life cycle model is developed in a hierarchical manner by adding the most important activities until error requirements are satisfied or network complexity exceeds user-specified constraints.

Results and Discussion

The framework is applied to an illustrative example for building a hybrid LCA model. Since this is a constructed example, the results can be compared with the actual impact, to validate the approach. This application demonstrates how the algorithm sequentially develops a life cycle model of acceptable uncertainty and network complexity. Challenges in applying this framework to practical problems are discussed.

Conclusion

The presented algorithm designs system boundaries between scales of hybrid LCA models, includes or omits activities from the system based on path analysis of environmental impact contribution at upstream network nodes, and provides model quality indicators that permit comparison between different LCA models.

     

Status update on LCA studies and networking in Tanzania

Purpose

Life cycle assessment (LCA) has become a standard for assessing what impacts do products and/or services have throughout their entire life cycle. Since the inception of LCA technique, studies have been conducted in different parts of the world, including Tanzania. This study describes the current status of LCA, capacities, and networking in Tanzania. The study has identified what has already been done and potential research gaps that could be explored in future LCA studies.

Methods

A state-of-the-art review was conducted on published articles, reports, and other materials on LCA in Tanzania (covering a time frame of 1990–2015) which were searched on databases of scientific research and the general internet using a combination of keywords: “life cycle assessment and Tanzania,” “LCA and Tanzania,” and “life cycle assessment and LCA and Tanzania.” Reviews were on current status, research gaps, and the need for future research. Information related to education or training activities and networking were also gathered and reviewed.

Results and discussion

Literature review has revealed that in Tanzania the first LCA study was published in 2007. Few articles and reports were identified in which LCA technique was used mainly for academic research in agriculture, electricity generation, charcoal, biodiesel production from jatropha oil, bioethanol production from sugarcane molasses, production of biofuels from pyrolysis of wood, and production of charcoal from sawmill residues. The very small number of LCA studies conducted in the country could be due to the lack of skilled personnel, lack of local data, and lack of research funds. Tanzania Life Cycle Assessment Network was created to link LCA practitioners and to promote and support further development of LCA in the country. Also, LCA potential is huge yet to be fully explored.

Conclusions

This state-of-the-art review is the first of its kind that summarizes and puts together all LCA studies in Tanzania. Most studies faced the challenge of lack of local data, which resulted to the use of secondary data from the literature. In LCA, the use of data from different geographical conditions could cause bias of the results and consequently could affect the decision made or to be made from the study. In this regard, the study recommends the establishment of national LCI database to solve this problem. Also, most studies covered only few impact categories prompting for full LCA studies in future studies. The study also found that there is a need to establish regular LCA training and courses for capacity development.

     

Characterisation of social impacts in LCA

Background, aim, and scope  

The authors have suggested earlier a framework for life cycle impact assessment to form the modelling basis of social LCA. In this framework, the fundamental labour rights were pointed out as obligatory issues to be addressed, and protection and promotion of human dignity and well-being as the ultimate goal and area of protection of social LCA. The intended main application of this framework for social LCA was to support management decisions in companies who wish to conduct business in a socially responsible manner, by providing information about the potential social impacts on people caused by the activities in the life cycle of a product. Environmental LCA normally uses quantitative and comparable indicators to provide a simple representation of the environmental impacts from the product lifecycle. This poses a challenge to the social LCA framework because due to their complexity, many social impacts are difficult to capture in a meaningful way using traditional quantitative single-criterion indicators. A salient example is the violation of fundamental labour rights (child labour, discrimination, freedom of association, and right to organise and collective bargaining, forced labour). Furthermore, actual violations of these rights somewhere in the product chain are very difficult to substantiate and hence difficult to measure directly.