Dr Andrew Hudson, Eurofins BLC Leather Technology Centre

The manufacturing of footwear uses a high number of components and a wide variety of materials which are sourced from all over the world. As such, the entire life cycle of a footwear product from all the individual raw materials (cradle) through component and shoe production, consumer use and end-of-life (grave), has a significant impact on the environment in terms of carbon footprint, land use, water usage and much more.

In order to identify opportunities to reduce the environmental impact of footwear, the industry needs to be able to establish which parts of the supply chain make the biggest contribution. A key tool to enable an assessment of the overall supply chain is a Life Cycle Assessment (LCA) which is a science-based approach to gathering data specific to an item of footwear. Unfortunately, a full LCA is a typically expensive and resource intensive approach which can take many months to gather the data to provide sustainability insights. For these reasons, LCAs have not become mainstream and have been mainly limited to larger organisations assessing a relatively small number of specific styles of footwear.

To address these issues, a new Footwear Impact Calculator based on LCA principles has been developed which enables non-expert ‘Users’ to undertake an assessment of a wide variety of footwear styles quickly and inexpensively. The output of the calculations provides meaningful and actionable data to identify areas for improvement.

Sustainability

A simple assessment of the number of different components and materials in any given shoe, along with considerations of the level of manual operations and locations of production and retail countries, shows that the manufacture of footwear is a resource-intensive industry operating within a truly global supply chain. As such, the sustainability impacts of the footwear sector in the context of the environment, society and governance (ESG) have the potential to be significant. Whilst sustainability is often considered only in the context of the environment, the reliance of the industry on labour-intensive manufacturing leads to the risk of creating labour exploitation, human right abuses and poor working conditions. Equally, good governance can only be achieved with robust systems and processes to identify, assess and manage ESG risks.

As the footwear industry extends from raw material extraction through manufacturing into consumer use and then repair/reuse/recycling and finally into disposal, understanding the sustainability performance of a product can only be achieved by knowledge of impacts along the entire supply chain. The material and footwear manufacturing stages can often account for 70% of the overall sustainability impacts which demonstrates that it is not sufficient to only make improvements in areas under your direct control e.g. your own direct operations. It is also necessary to look at areas you can influence e.g. your supplier’s operations and distribution channels.

Whilst many footwear brands have limited knowledge of their supply chain, legislation is driving larger companies to have full visibility back to the point of raw material extraction, make appropriate sustainability commitments and improvements and share this information with stakeholders and consumers. Examples of such legislation include the European Corporate Sustainability Reporting Directive (CSRD), the German Supply Chain Due Diligence Law and various USA ‘Fashion Acts’. In addition to forcing industries to become more sustainable, legislation is also defining how environmental claims can be made and what is required to ensure that these can be substantiated. The proposed European Green Claims Directive is a key example of how governments will ensure that consumers are protected against spurious green claims and greenwashing.

Need to measure

Measuring the sustainability impacts of a material, product, operation or supply chain, is a key element of defining what the current situation is and how potential improvements can be made and communicated both within an organisation and to stakeholders, including consumers and investors. The proposed Green Claims Directive will look to introduce specific direction on how environmental claims can be substantiated which will centre on scientific evidence of claims linked to significant environmental improvements.  As such, the use of credible science-based metrics (SBM) will be crucial in supporting any green claims that an organisation would like to make to their consumers.

Due to the supply chain complexity and diversity of footwear materials, the opportunities for actors within the supply chain to make significant environmental improvements is vast.  Many organisations have chosen to focus on materials, either by selecting ‘Environmentally Preferred Materials’ (EPM’s) or by ensuring use of the best versions of a specific material. Other brands have focused on increasing the use of recycled content or even using bio-based materials.

An alternative or additional approach is to consider other environmental impacts within the supply chain. Examples of these include optimising packaging (e.g. reducing or eliminating, use of recycled materials, etc) or moving from a global to near-sourced distribution model. Whilst each of these approaches many have environmental benefits, the real issue is whether these changes are significant and how the benefits can be comparably measured. The question also remains whether these individual strategies are addressing the biggest impact areas within the supply chain.

LCAs

To identify the key environmental impacts within a supply chain, it is necessary to consider not only the shoe manufacturing process, but the entire process both upstream and downstream from this stage. Upstream impacts include those for the raw material extraction for each material used in each component, such as plastics and rubbers, animal-based materials, virgin and recycled textile materials, packaging and trim materials.  Downstream includes distribution to the warehouse and retailer and then consumer use and final end-of-life (recycle/disposal). To identify and measure all these impacts, an approach called a Life Cycle Assessment (LCA) has been developed as a powerful tool by which organisations can assess the environmental impact of an item of footwear in the context of its entire life cycle. Such assessments provide insights into where the major sustainability impacts are and enable targeted and impactful improvement strategies to be developed.

Whilst full and complete LCAs can provide detailed insights, they have some significant disadvantages which prevent them from becoming a mainstream tool. The first issue is that LCAs require significant resource and time in gathering, assessing and calculating all the data that is required at each stage of the supply chain. The second key issue is that different approaches can be taken by different organisations conducting LCAs on similar footwear products which prevents direct comparisons between different footwear and footwear supply chains.  The third issue, which arguably is the key drawback, is that LCAs can be very expensive.

Recognising the limitations in comparing LCAs, the European Commission has drafted Product Environmental Footprint Category Rules (PEFCR) to provide guidance on how the environmental footprint of footwear should be calculated. By defining which life cycle stages and processes should be included in the ‘system boundaries’ for footwear, organisations will be clearer on how to calculate an LCA and comparisons between different LCAs will be relevant.

Impact Calculator 

Whilst the PEFCR makes comparison between LCAs possible, it does not overcome the relatively high cost of performing a full LCA which can take months and cost many tens of thousands of dollars. To address this, a new footwear sustainability calculator has been created which is based on the draft PEFCR and LCA principles as described in IS0 14040 and ISO 14044. This Eurofins Footwear Impact Calculator is powered by SimaPro (developed by PRé Sustainability) and has been designed as a low-cost and intuitive tool that allows a user to identify potential sustainability impacts for a whole range of footwear styles.

The tool is an online system which can be used to assess the entire supply chain of a finished pair of shoes including packaging. The product lifecycle scope is from cradle to grave, covering the production of materials and of the shoe, transport, use and end of life of the shoe. The tool uses a variety of secondary data sources including those from the PEFCR and ecoinvent version 3.8 life cycle inventory database. The product’s end of life was modelled using the Circular Footprint Formula (CFF) developed by the European Commission as specified in the PEFCR.

The strength of the tool is that it does not require any LCA or sustainability expertise on the part of the user to obtain meaningful and actionable data. It guides the user through a simple process by means of drop-down menus relating to materials used in the construction of the shoe, manufacturing and retail locations (countries), retail channels (online and in-store) and levels of consumer wear (use).  From this information, the tool estimates the three key environmental impact indicators for footwear:

• Carbon footprint (climate change)
•  Land use
•  Water use

Within each of these a report is generated which itemises the top 10 contributing factors for each impact category within the overall footwear’s cradle to grave lifecycle.

The tool has been designed for two key types of user:
1. Users who do not have detailed Bills of Materials (BOMs) for the footwear;
2. Users who have detailed BOMs including weights of individual components (e.g. weight of the upper).

For those users who do not have detailed information, the tool has created footwear templates for a variety of men’s, women’s and children’s shoes which has estimated the amounts of different materials that would be used for the various footwear components. By simply selecting, for example, leather as the upper, EVA as the outsole, polyester as the lining, etc. the tool will calculate the impact values based on average weights of each material in each component. Where detailed BOMs are available, a Create Custom Shoe Type option will allow the user to input specific weights of each material in each component e.g. the upper is 78.3g of leather and 14.2g of polyester, the outsole is 112.4g of EVA, etc.  The tool will then estimate the environmental impacts very specifically to the shoe under review.

Using the calculator

It is important to understand that the results from the Eurofins Footwear Impact Calculator are derived from secondary data sources rather than data that has been collected specifically for the actual processes and materials used in the real-life supply chain (primary data). As such, results from the tool should not under any circumstances be used to make any sustainability claims.

The real benefit of the tool is that the results of the calculations can be used by brands, retailers, designers, technologists and sustainability managers to identify opportunities to target improvements in the areas of highest environmental impact. It is estimated that up to 70-80% of environmental impacts will be affected by choices made during the design phase. By using the tool as a method for screening different footwear styles, comparing different materials for each component and assessing the effect of manufacturing locations, the results can be used as a precursor for determining which aspects of the life cycle should be a focus. From this, primary data can be collected both prior to and after making product changes, the results of which can be used for sustainability claims.

Conclusions

Understanding the environmental impact within a footwear’s lifecycle from cradle to grave is critical for the industry to be able to make meaningful improvements. LCAs use a science-based approach to collect and assess appropriate data to define such impacts and highlight potential areas of improvement. Whilst full LCA studies provide company-specific data, they can be costly and resource intensive. The new Impact Calculator tool offers the industry a pragmatic, inexpensive and rapid way to understand potential impacts within a supply chain based on the materials used in each component, manufacturing countries of both input materials and the footwear along with logistics, distribution channels and countries of retail. The output from such studies can be used for both determining where sustainability improvements might be made, but also where company-specific data should be sourced for before and after any sustainability improvements, the data from which can be used appropriately in consumer communications.

Disclaimer: Please note that results from the Eurofins Footwear Impact Calculator cannot be used for making sustainability claims. The tool provides an estimation of your environmental footprint based on LCA principles, but it does not replace a full LCA study. The calculator does not use company-specific data and therefore results are not PEFCR compliant. The tool has undergone internal verification at PRé Sustainability but has not been externally verified.

ALL CREDITS: EUROFINS BLC

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