Towards Sustainable Use of Chemicals in the Textile Industry: How life cycle assessment can contribute
The use of chemicals in the textile industry is a topic that has been given increasing attention in recent years. Hazardous chemicals are found in textile consumer products on a regular basis, and there is an increased awareness of the health and environmental impact caused by emissions of hazardous chemicals in the countries where textile production occurs. There is a need for practical tools that can be used to assess and reduce the exposure of people and nature to harmful chemicals.
Life cycle assessment (LCA) is a quantitative tool that evaluates the environmental pressures and benefits associated with the full life cycle of products or services, potentially comprising a broad range of environmental impact categories, such as climate change, acidification, resource depletion and toxicity. However, accounting for the use and emission of chemicals is a weak point in LCA practice and calculating the toxicity impact is a weak point of LCA methodology, and therefore, toxicity impacts are habitually excluded from LCA studies. The drawbacks of excluding toxicity in environmental evaluations are especially critical in assessment of textile products since the textile industry is an intense user of chemicals, both for fibre production and during the textile manufacturing process.
The research presented in the thesis and the two papers intends to improve LCA methodology and practice so that use and emissions of textile chemicals can be included in LCA studies of textile products, and the results thereof can provide useful guidance to decision makers in the textile industry. Three research questions are answered: 1) if the toxicity impact potential of textile chemicals is covered in LCA studies of textile products, 2) if the environmental performance ranking of textile products will be affected by including the toxicity impact potential of textile chemicals in LCA studies and 3) what the main challenges are in using LCA to assess the toxicity impact potential of textile chemicals. The research method has been designed to explore the challenges and suggest improvements to LCA methodology based on literature studies, case studies and triangulation with other applicable methods for calculation of toxicity impact potential.
It is concluded that the toxicity impact potential of textile chemicals is today only to a marginal extent covered in LCA studies of textile products. The use and emission of textile chemicals are in general excluded from life cycle inventories. In some cases where textile chemicals have been included in the inventory they are still excluded from the toxicity assessment. It is further concluded that the total environmental performance ranking of textile products can be affected by including the toxicity impact potential of textile chemicals in LCA studies. In addition, quantification of toxicity impacts in LCA allows for the comparative significance of chemicals to be revealed. By providing such knowledge LCA allows thus for comparison of the effectiveness of different management interventions. Several challenges have been identified which must be overcome for LCA to contribute to the sustainable use of chemicals in the textile industry. The main challenges are the complexity of calculating toxicity impact potential in LCA: the complexity of the textile production chain; the diversity in both the use and properties of textile chemicals; the lack of guidance in the area in the literature and the lack of validation methods. If these challenges are addressed, LCA can contribute to a sustainable use of chemicals in the textile industry with its quantitative approach, its life cycle perspective and its holistic view of environmental impact.