Environmental impacts of cotton and opportunities for improvement

Cotton — supplying approximately a quarter of global textile fibres — has various environmental impacts, including water use, toxicity, eutrophication and greenhouse gas emissions. In this Review, we identify these impacts across multiple life cycle stages. Environmental impacts at the cultivation stage depend on levels of irrigation, pesticide and fertilizer applications. At the textile manufacturing stage, impacts depend on energy infrastructure and manufacturing technologies. At the use phase, impacts depend on consumer habits related to buying, washing, drying and ironing. Depending on the impact category and country, cotton cultivation, manufacturing or use can dominate such impacts. For example, the use phase dominates greenhouse gas emissions in countries with carbon-intensive energy grids. Use of alternative fibres has the potential to reduce these environmental impacts, particularly jute and flax, which have much lower water demands. Opportunities for farmers, manufacturers and consumers to improve the environmental sustainability of cotton textiles include, among others, improving water-use efficiency in agriculture, innovative recycling and laundering less frequently. Future cotton sustainability assessments are needed to fill data gaps related to developing and emerging countries, the number of uses of a cotton garment and further environmental impacts such as salinization, as well as socio-economic impacts.