Control quantity or toxicity of textile chemicals? A case study of denim jeans in the warp-dyeing phase

Abstract

The extensive use and discharge of chemicals is one of the main factors leading to serious environmental pollution in the textiles and apparel industry. The chemical footprint (ChF) is a toxicity-based chemical management method that is used to quantitatively evaluate the potential toxic effects of chemical pollutants discharged during the production of textiles and apparel products on human health and environmental safety. Compared with the traditional quantity-based method, this method needs to simulate the entire process of chemicals from discharge to impact, involving a series of steps of fate, exposure and effect, which greatly increases the difficulty of modeling. A scientific question is whether it is worth spending so much effort to quantify the toxicity of chemicals. Taking the warp-dyeing phase of denim jeans as an example, this paper calculated the ChFs for both human and ecological toxicities of textile chemicals based on the USEtox model, and compared them with the values of discharge quantities. The results reveal that there is a certain inconsistency between the discharge quantity and toxicity of chemical substances. Relying solely on the amount of chemicals discharged can sometimes lead to misjudgments, emphasizing the importance of controlling the toxicity of chemicals.

Vat Dye Molecule–Proton Dual Adsorption Catalysis Based on Molybdenum Disulfide for Sustainable Textile Dyeing

“…As a symbol of a free lifestyle, denim fabric and clothing have consistently been beloved by global consumers, with an annual global production exceeding an astonishing 9 billion meters and a value exceeding 25 billion USD. − However, the production process of denim garments, particularly the dyeing stage, has caused significant environmental pollution. − This pollution is primarily due to the excessive use of indigo dyes and reducing agents, such as sodium dithionite (Na 2 S 2 O 4 ), during the dyeing process. Based on current industrial practices, the dyeing process for indigo denim fabric consumes approximately 2 t of the toxic and corrosive Na 2 S 2 O 4 per ton of fabric, with an estimated 60–70% of this amount being discharged into the environment .…”