From production to waste disposal: A life cycle assessment of fast fashion polyester and cotton T-shirts

Fast fashion apparel causes significant environmental impacts due to its high production frequency, short lifespan, and global supply chains. However, existing life cycle assessment (LCA) studies of clothing have not yet fully considered the specific conditions of fast fashion. This study employed an LCA methodology to systematically compare the environmental impacts of polyester and cotton T-shirts from production to end-of-life disposal throughout their entire life cycles within the fast fashion context, using one T-shirt under a 20-wash use scenario as the functional unit. By combining transport-related sensitivity analyses with fast fashion scenario analyses focusing on transport modes and clothing lifespan, this study aims to address these limitations and conduct a more targeted assessment of key environmental issues within the fast fashion system. The environmental impacts across multiple categories were evaluated, followed by the estimation of greenhouse gas (GHG) emissions for each stage. Results indicated significant differences in environmental performance between cotton and polyester T-shirts across various impact categories. Polyester T-shirts exhibited considerably higher emissions, reaching 9.62 kg CO 2 eq per functional unit, compared to 6.1 kg CO 2 eq for cotton T-shirts. Sensitivity analysis showed that polyester and cotton T-shirts' carbon emissions were both more sensitive to transportation-related parameters, particularly air freight distances. Scenario analysis indicated that altering transportation modes and extending product lifespans could significantly reduce the environmental impact of fast fashion. The results suggest that improving the environmental performance of fast fashion garments should prioritize reducing air transport and extending product lifespan, as both significantly reduce environmental impacts.