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You will not find bamboo textiles listed on ethiquette.ca. While some textile articles may be derived from bamboo pulp, they have
not been made from natural bamboo fibre and are, in fact, rayon fibres
made through a chemical process.
On January 27th 2010, the Competition Bureau of Canada announced that more than 450,000 textile articles have been re-labelled
and over 250 Web pages corrected as a result of the Bureau's efforts to
ensure that textile articles derived from bamboo are accurately
labelled and advertised.
“The Bureau took action because of concerns over potentially
misleading labelling and advertising in the marketplace with respect to
textile articles labelled "bamboo". While such textile articles may be
derived from bamboo pulp, they have not been made from natural bamboo
fibre and are, in fact, rayon fibres made through a chemical process.
Consumers may be paying a higher price for such articles on the
assumption that the articles have environmentally friendly or health-enhancing
qualities. The Bureau is not aware of any consumer textile articles
made of natural bamboo fibre currently being sold in the Canadian
marketplace.“
Read the full announcement
keywords / mots clés : bambou, vêtements bambou, bamboo clothes
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Bamboo Textiles may or may not be eco-fr
Written by Hurter on 2009-05-26 15:30:26
I am a consultant with 30 years experience in the pulp and paper industry working with wood and nonwood fibre raw materials such as sugarcane bagasse, cereal straws, bamboo, reeds, grasses, hemp, flax, jute, kenaf etc. Most of my work has been with nonwood fibre raw materials.
There are no spinnable fibres in natural bamboo. Bamboo textiles are made from a regenerated cellulose product called viscose rayon.
In my opinion, the jury is still out regarding whether or not bamboo textiles can be classified as eco-friendly. Bamboo fabrics should not be excluded from being eco-friendly because of the conversion process as it is possible to develop conversion processes that would allow eco-friendly labeling.
Bamboo textiles in our markets come primarily from several Chinese companies. The problem is that no one to my knowledge has done any eco-audits on the supply chain from the bamboo growing to the finished textile. Until this is done by an independent third party, no one can claim that bamboo textiles are or are not eco-friendly.
Let's take a look at a few of the key issues involved (and there are others that are not mentioned here).
First, one must question the source of the bamboo raw material. Did it come from a natural bamboo forest or from farmed bamboo? If it came from a natural forest, this is not good as harvesting natural bamboo forests upsets local biodiversity for both flora and fauna. If it came from farmed bamboo, then the first question is how was the farm established? Was it done using the traditional method of transplanting bamboo from an existing natural forest (which will disrupt the habitat in the existing forest) or was it done using modern tissue culture techniques to mass produce the planting material in a lab? Next, one needs to question if the land used for the bamboo farm was formerly land used for food production? Another question is water consumption as bamboo needs lots of water to grow under optimum conditions. Is there enough rainfall to sustain the bamboo farm or is irrigation water required, water that may have a better use for growing crops or for drinking. And, the claim that bamboo does not require fertilizer depends on the soil type. If good soil is available, this is true, but if the farm is on marginal land not suited to food crops, fertilizers may be necessary.
Now let's take a look at the processes involved to make viscose rayon from bamboo. It is a two step process with the first step being the manufacture of a high purity dissolving pulp in a chemical pulp mill that is similar to a woodpulp mill and the second step is converting the dissolving pulp into viscose rayon in another chemical process.
The typical pulping process used for making dissolving pulp is a pre-hydrolyzed Kraft process followed by bleaching and drying. The first step in the process is an acid hydrolysis typically using sulphuric acid to remove some of the hemicellulose. The next step is Kraft cooking using sodium sulphate to remove lignin (the glue that holds the plant together) and inorganic material. This is followed by pulp washing, screening and cleaning. Then the pulp is bleached using a variety of chemicals to remove more hemicellulose so that after bleaching you have a high purity dissolving pulp - typically 90% or more alpha cellulose. Then the pulp is dried and shipped to market.
Yes, the process uses lots of chemicals but their use can be in an eco-friendly manner if the mill is properly designed to Western standards.
So, what are some major eco-related questions regarding dissolving pulp manufacture?
1. Is the dissolving pulp mill designed to best available practices used in North America or Europe, or to less stringent requirements of the Chinese government?
2. Does the mill have a chemical recovery system to recover the cooking chemicals from the wash water (black liquor) for reuse in the pulp mill? If it does not have an efficient chemical recovery system, the pulp mill will be heavily polluting.
3. What chemicals are used in bleaching? Many mills in Asia still use elemental chlorine for bleaching, a practice that has been stopped in the West for years as this creates dioxins (organochlorides that are known carcinogens) that end up being discharged from the mill into local streams and rivers. Or does the mill use and elemental chlorine free (ECF) or totally chlorine free (TCF) bleaching sequence. In general, ECF bleaching is the Western standard to minimize eco-related issues.
4. What is the energy source for the mill? Is it low grade, heavily polluting coal or high quality oil or natural gas?
5. What quality standards are used for effluent treatment, air emissions etc.? Are they North American or European high standards, or lesser Chinese standards?
In the viscose rayon process, the dissolving pulp is steeped in caustic soda to completely dissolve the cellulose and then treated with carbon disulphide to create the rayon filament.
1. How is the effluent from this process treated before it is returned to the environment?
2. Carbon disulphide is known to cause respiratory problems for workers. Are measures in place at the factory to ensure that workers are not exposed to it?
3. What quality standards are used for effluent treatment, air emissions etc.? Are they North American or European high standards, or lesser Chinese standards?
It is entirely possible to manufacture bamboo textiles in an eco-friendly manner just as rayon and other regenerated cellulose fabrics are made from wood in the West.
But, until there are independent third party eco-audits from bamboo growing to the finished bamboo textile from China and possibly elsewhere, one should be cautious regarding any claims that bamboo fabric is eco-friendly. It still needs to be proven.
If anyone wishes to contact me regarding the above comments, I can be reached in Ottawa at 613-749-2181.
Bob Hurter, MBA, P. Eng.
President
HurterConsult Inc.
Ottawa, ON
Canada
www.HurterConsult.com
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