I realise that for many this is quite a shock given we've been once again led to believe that a particular fabric is "good" for the enivironment, which is particularly disheartening when the designers actually know this information yet still purport it to be both ethical and environmentally sound.
One of the best explanations of why most bamboo fabric is definitely not ethical nor eco-friendly is by @patagonia - I like to add to this by considering the carbon emissions in a way that although bamboo as a crop does sequester high amounts of carbon, and does a better job than say hemp and cotton - both purpose grown crops, although as we know hemp and bamboo require less water than cotton, regardless of its organic status. So to add to this complexity is the fact that Lenzing's forests are FSC certified but also great portions of the trees are stripped so they regenerate. A tree takes 20-30 years to reach its capacity to sequester maximum carbon, so the more we leave them, the better it is. The bigger the plant eg trees vs bamboo, the larger sequestration impact as well. So this just adds to the information below on the other very non-human and non-environmentally friendly status of bamboo fabric.
I will say though that I’ve not searched hard for a closed loop bamboo because I’m 200% happy with supporting Lenzing fabrics who tick off all my essential points. Non-closed loop bamboo is more likely to be detrimental to workers’ health & chemical dumping as you read below but also for the better job that tress do for carbon sequestration.
Patagonia writes“.... The solvent used for this process is carbon disulfide, a toxic chemical that is a known human reproductive hazard. It can endanger factory workers & pollute the environment via air emissions & wastewater. The recovery of this solvent in MOST viscose factories is around 50%, which means that the other half goes into the environment. Other potentially hazardous chemicals are also used. Because of these environmental issues, Patagonia does not use rayon fabric or bamboo fabric made by the viscose process. Our material developers have been investigating bamboo since 2003, but since almost all available bamboo fabric is made using the viscose process, we do not use bamboo fabric in our product line. We are aware of some linen-type bamboo fabric that is processed as bast fiber, but currently we are not using it because we have hemp fabrics that perform well in this type of application. ... .
We have searched for an alternative fabric with these attributes, but with less harm to the environment. The best we have found is called Tencel®, a branded name of lyocell fiber. #tencel is also a regenerated cellulose fiber, but processed with a non toxic spinning solvent in a closed-loop system.
The raw material is wood pulp harvested from eucalyptus tree farms, & the pulp is certified by the Forest Stewardship Council® (FSC). It is possible to use bamboo, or other sources of cellulose, but eucalyptus yields the best quality fiber with the least amount of waste.
Therefore we think this process is the best available option. Read on at www.patagonia.com
And Download STSC's Lenzing Textiles Price List and Book that outlines the fabrics we wholesale including LENZING TENCEL™ and MODAL and Lenzing's latest; TENCEL™ LUXE, ECOVERO™ viscose and TENCEL™ x Refibra