Silk is a natural product that is easily bio degradable and does not require any chemical solvents to produce unlike most bamboo fiber which is often made using toxic carbon disulfide which is an air and lung toxin.
Most fiber labeled as "bamboo" is not exactly what it seems, while one may have the impression that bamboo is mechanically processed from it's long grass like form into a fabric, much like linen is processed from a short grass into a fabric by means of beating and mechanically stripping, this is not the case. Most bamboo fabric is simply Rayon, Rayon is a 'semi-synthetic' fabric made of cellulose and processed with chemical solvents, that cellulose can come from many sources traditionally tree bark was used but any cellulose containing plant can be used.
The rayon process uses chemicals like lye and carbon disulfide to strip the cellulose from the material of choice. Once the cellulose is isolated, unspecified inorganic and organic chemicals are added to polymerize the slurry, essentially restructuring the isolated cellulose from it's natural state into plastic like chains. The slurry is then acidified to allow the carbon disulfide to off gas, it is possible to collect and re-use the carbon disulfide but insuring this is actually happening when many manufacturing plants are thousands of miles from the end product consumer is challenging. There is a serious problem with carbon disulfide injury in textile workers world wide.
Bamboo Rayon is possibly more environmentally friendly than rayon made from wood pulp as bamboo grows incredibly fast, requiring less land to grow the cellulose source but it is definitely more eco-friendly than it's fully synthetic counterpart polyester.
Polyester which is made from petroleum and uses many caustic chemicals in it's manufacture. Nearly 70 million barrels of oil are used each year to make polyester around the world, which is now the most commonly used fiber in making clothes. But it takes more than 200 years to decompose. A team at Plymouth University in the UK spent 12 months analyzing what happened when a number of synthetic materials were washed at different temperatures in domestic washing machines, using different combinations of detergents, to quantify the microfibers shed. They found that an average washing load of 6 kg could release an estimated 137,951 fibers from polyester-cotton blend fabric, 496,030 fibers from polyester and 728,789 from acrylic a major source of micro plastic pollution.
We urge our customers to avoid buying polyester fabric clothing. It is a huge, long term pollutant to our environment, and if you must buy a polyester item please buy something that you will use for a long time, that is of a good quality so it lasts and that you LOVE so you won't feel the need to have multiples of the same item.