Life cycle assessment of cotton T-shirts in China

Nowadays, environmental sustainability of textile has gained much attention from government and suppliers due to the resource consumption and pollutant emissions. Besides, different consumer behaviors can result in quite different environmental consequences mainly in terms of water and energy consumption. Therefore, it is necessary to systematically evaluate the environmental impacts of textiles from a life cycle perspective to improve the sustainability of textiles especially for China, the biggest producer, exporter, and consumer in the world.

This study is conducted according to the International Organizations for Standardization’s (ISO) 14040 standard series. The declared unit is a piece of 100 % cotton short-sleeved T-shirt. The production data mainly come from field investigations of representative mills in China. The use-phase data are mainly from 924 questionnaires of Chinese residents. The secondary data from databases, literatures, and authoritative statistical data are supplemented in case primary data are not available. The potential environmental impacts are evaluated using the CML2001 and USEtox methodologies built into the GaBi version 6.0 software. We determine hotspots throughout the life cycle of the cotton textile considering the impact categories of abiotic depletion, acidification potential, global warming potential, photochemical ozone creation potential, eutrophication potential, water use, and toxicity.

The results of the study show that cotton cultivation, dyeing, making-up, and use-phases are the main contributors to the environmental impacts. In particular, fertilizer, pesticide, and water use in cotton cultivation, coal, dyes, and auxiliaries use in dyeing, electricity use in making-up, detergent and water use in washing, and electricity use in spinning are the hotspots based on the life cycle impact assessment (LCIA) results. The use-phase scenario analysis shows that compared with machine washing, electric drying, and ironing share the majority of electricity consumption. Compared with Americans, Chinese washing habits are much more environmental-friendly and bring much lower environmental impacts in the use stage.

Energy consumption, chemical use, and water use are main contributors to most impact categories, which help us to find hotspots and potential improvements of sustainability.