Sustainability assessment of denim fabric made of PET fiber and recycled fiber from postconsumer PET bottles using LCA and LCC approach with the EDAS method

Abstract The textile industry is under pressure to adopt sustainable production methods because its contribution to global warming is expected to rise by 50% by 2030. One solution is to increase the use of recycled raw material. The use of recycled raw material must be considered holistically, including its environmental and economic impacts. This study examined eight scenarios for sustainable denim fabric made from recycled polyethylene terephthalate (PET) fiber, conventional PET fiber, and cotton fiber. The evaluation based on the distance from average solution (EDAS) multicriteria decision-making method was used to rank scenarios according to their environmental and economic impacts, which are assessed using life cycle assessment and life cycle costing. Allocation, a crucial part of evaluating the environmental impact of recycled products, was done using cut-off and waste value. Life cycle assessments reveal that recycled PET fiber has lower freshwater ecotoxicity and fewer eutrophication and acidification impacts. Cotton outperformed PET fibers in human toxicity. Only the cut-off method reduces potential global warming with recycled PET. These findings indicated that recycled raw-material life cycle assessment requires allocation. Life cycle cost analysis revealed that conventional PET is less economically damaging than cotton and recycled PET. The scenarios were ranked by environmental and economic impacts using EDAS. This ranking demonstrated that sustainable denim fabric production must consider both economic and environmental impacts. Integr Environ Assess Manag 2024;20:2347–2365. © 2024 The Author(s). Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Key Points This study investigated denim fabrics produced using recycled polyethylene terephthalate (PET) fiber instead of virgin cotton and conventional PET fiber in eight scenarios. The life cycle cost (LCC), life cycle assessment (LCA), and evaluation based on distance from average solution methodologies were used to analyze, and a sensitivity analysis was performed to assess LCA uncertainty. Using recycled PET with the cut-off method instead of cotton resulted in positive environmental outcomes across most categories, indicating a significant reduction in impacts such as global warming, stratospheric ozone depletion, and ionizing radiation. Using recycled PET with the waste valuation method often leads to more negative outcomes than the cut-off method, suggesting that the allocation method plays a crucial role in determining the environmental benefits of recycled materials.