A comparative life cycle assessment of textile fiber production processes: Hemp versus cotton

Abstract

Cotton, although a dominant fiber in the textile industry due to its high durability and strength, tends to have unsustainable production, leading to the search for alternative fibers such as hemp. This study evaluated the impacts of cotton and hemp fiber production through a comparative environmental life cycle assessment, focusing on farming, harvesting, and fiber processing. The functional unit used was 1 hectare of cultivated land. Using data from peer-reviewed literature, eutrophication, global warming, and acidification potential of producing these fibers was quantified. While both fibers presented impacts in these three categories, cotton demonstrated the highest impacts in all three (69.6 kg N eq. for eutrophication, 7903 kg CO₂ eq. for global warming potential, and 65 kg SO₂ eq. for acidification). Not only did hemp exhibit lower impacts (3.6 kg N eq. for eutrophication, 1374 kg CO₂ eq. for global warming potential, and 15 kg SO₂ eq. for acidification), but it also offered secondary benefits such as carbon sequestration and versatile uses. Due to data limitation, a sensitivity analysis was conducted to assess the impact of variation (± 20 %) in key inputs: energy, electricity, and fertilizer usage. Overall changes to all three impact categories were well below the 10 % threshold for both fibers, suggesting the processes evaluated are reliable and easy to manage under varying conditions. However, more innovative and systematic changes such as the use of more efficient equipment, are needed. These findings will provide valuable insights to key stakeholders and consumers who aim to enhance the sustainability of the textile industry.