Blue Rivers - Toxic Indigo Dye

The biggest targets of fabric dyes, including indigo dye, are the local water systems to where it is used. Countries known for large-scale clothing manufacture like India and China  have had similar experiences with toxic indigo waste being dumped into ecosystems leading to rivers of blue or black.   In 2017, several dogs in Mumbai  started to appear light blue. This was found to be because a local manufacturing company decided to dump toxic waste from the indigo dyeing process into the river that the dogs frequented and hunted food from. Local citizens campaigned and demanded restoration of the river until the government shut down the factory.   The Pearl river in China is also under strain from the large amounts of toxic waste dumped from nearby factories. Much of that waste is from fast-fashion factories that cut corners in recycling waste water and responsible disposal. 

Mordants kill plants and can poison marine life and surrounding organisms when rivers, groundwater and ecosystems are polluted with them. Similarly, the toxins and heavy metals that make their way into rivers and groundwater can penetrate plants and seafood, making their way up the food chain until humans consume them at risk to their health. Textile workers who are responsible for the dyeing process of Indigo are obligated to wear skin, eyes and lung protection when dealing with indigo dyes. These same toxins and chemicals are then discarded into the local ecosystem.   Reports of dogs turning blue, and rivers changing color are even more insidious than they first sound. Synthetic indigo dye decomposes very slowly. When it changes the color of the rivers, the plants are starved of sunlight which makes them unable to photosynthesis and can kill them. The water is then lacking in oxygen which leads to the suffocation of aquatic animals.

The future of indigo-dyed denim is likely to evolve with new scientific technology. One biotech firm, Tinctorium, have been working to genetically engineer bacteria  so that they produce indigo in a similar way to a natural indigo plant. Another scientist, Juan Hinestroza, is researching the possibility of using nanotechnology  to apply dye to clothing fibres without mordants or other toxins. 

Jemaya Greylenner