Have you ever wondered about textile dyes and the effect they have on the environment? The purpose of this blog is to shed a neon light on the subject. Be forewarned: the beautiful colors in your closet may look different after reading… The textile dyeing and finishing industry has a very dirty past, and due to environmental concerns, is finally facing pressure to clean up its act. The industry uses huge amounts of chemicals and vast amounts of water (100-150 liters of water to process 1 kg of textile material) and is known for poisoning rivers by dumping mega amounts of toxic, untreated wastewater (effluent) directly into waterways. 
Azo dyes and pigments are used to color most textiles and leathers. They are dangerous to work with, giving off carcinogenic amines. The name Azo is derived from the Greek a (not) + zoe (to live). With a name like that, it’s no wonder these dyes have an adverse affect on water resources, soil fertility, and eco-system integrity. The industry also uses significant amounts of bleaches, acids, alkalis, salts, stabilizers, surfactants, fire retardants, softeners, starches, heavy metals, and an assortment of dyes (acid, basic, disperse, mordant, reactive, sulphur dye, pigment, and vat). Most of these chemicals are applied using water as a medium. With the price of water consumption and effluent disposal increasing, some companies are beginning to look at ways to reduce water usage and find viable ways to treat effluent, while many dye houses will continue to use up local water supplies and dump untreated toxic wastewater into streams and rivers until the cows come floating home. 
Air-dyeing is a waterless dyeing system, which uses less energy and no auxiliary chemicals and is twice as fast. Nike and IKEA have invested in DyeCoo, a waterless dyeing company, and Adidas’ DryDye shirts are made using this system. Currently air-dyeing industrial machines only work on polyester and are very expensive, but carbon dioxide, the substance used, is inexpensive and is also re-used in the process, saving money and resources. While waterless dyeing may be more environmentally friendly, synthetic dyes are still used, however. Low-impact dyes have been classified as eco-friendly by the Oeko-Tex Standard 100 (an international certification process). These dyes generally do not contain toxic chemicals or mordants (used to fix dye to fiber), require less rinsing, and have a high absorption rate, saving energy and creating less wastewater than conventional methods. Fiber-reactive dyes are low-impact synthetic dyes that bond directly with fibers and don’t require mordants or use heavy metals or known toxic substances. They use lower temperatures and shorter cycles, saving water and energy, and are now available in brighter and richer colors as well as having excellent colorfast properties
Low-impact, fiber-reactive dyes are the dyes of choice in eco-fashion, and Oeko-Tex 100 certified dyes are used on organic textiles to qualify for the GOTS certification. The Global Organic Textile Standard is in place to cover all of the post-harvest production and processing of fibers. Stay tuned for If Textiles Could Talk part 2, about “natural” dyes.