Can you find out what’s in your fabric?

28 03 2013

I was one of those people who thought that manufacturers were not “allowed” to sell me any product that contained something that might harm me. As I quickly learned, that’s basically not true in the United States – especially with respect to fabrics. The EU is light years ahead of the US with their REACH program, designed to replace the most harmful chemicals with less toxic alternatives, but even that program focuses only on only the most high volume chemicals used in industry.
Let me just remind you why knowing what chemicals are used for processing your fabrics is important:
Because fabrics – all fabrics – are by weight about 25% finishing chemicals (i.e. dyes, finishes, softeners, etc.) And because the textile industry uses over 2000 chemicals routinely, how do we know the mix in the fabrics we’re living with are safe?
Well, you can ask the store where you’re buying the sheets or shirts – but they’ll probably look at you blankly.
You can demand information from the manufacturer. But often they don’t know the answers. To illustrate why this is, let’s take one example. Let’s pretend we’re a mill and we have just woven an organic cotton fabric, and we want to dye it. We can choose from many dyes, but settle on one called “Matisse Derivan” manufactured by Derivan Fabric Dye. Because dyes are made up of many chemicals, and because they’re proprietary, it’s next to impossible to find out what is in the particular dye you’re buying. So you might think the MSDS sheet would give us the information.
MSDS sheets are sometimes used to substantiate the “safety” of a chemical product by requiring the listing of chemical components by CAS number, which is a unique numeric identifier of a chemical substance which links to a wealth of information about that chemical. But the reality is that many of the chemicals used in industry (textile or otherwise) have never been evaluated for toxicity, and therefore in the toxicity evaluation there is no data to refer to. In addition, proprietary components do not need to be listed. So the sheets have inaccurate or missing information. According to a 2008 study, between 30 – 100% of products analyzed contained chemicals not declared on an MSDS.(1)
The MSDS sheet for Matisse Derivan (click here to see the sheet) for example, lists these substances in the composition of the dye:

SUBSTNACE                                   CAS NUMBER

  • Pigments                                             Various
  • water-based acrylic co-polymer      Proprietary
  • surfactants, dispersants, etc.           Various
  • ammonia                                             1336-21-6
  • water

In looking at an MSDS sheet, you might also find that any hazard classification or risk phase has “not been established” and “the toxicological properties of this product have not been thoroughly investigated”, or the hazard classification might be identified as “non hazardous” according to various codes, such as the TSCA. These codes are woefully inadequate as is now known (click here for more information) so to say that a chemical is non hazardous according to a code that dismisses all chemicals for which there is no data – well, you can see the problem.
There is also a lack of enforceable quality criteria, probably one of the reasons the sheets are of such poor quality.
Because testing has been done to establish wastewater criteria, some studies have shown what types of chemicals are found in textile wastewater from dyes, such as one which found benzidine, vinyl-p-base and 4-aminoazobenzene – all quite toxic.(2)
Once you get the information on the dyestuff used you’re one chemical component down  – and maybe 20 to go, because in most fabrics these functional areas also require chemical treatments:
Textile auxiliaries (such as complexing, wetting, sequestering, dispering agents; emulsifiers), textile chemicals (dyes, dye-protective, fixing, leveling agents; pH regulators, carriers, UV absorbers); finishes (stain, odor, wrinkle resistance).
And finally, even if you were able to find out which particular chemicals are used in a product, it’s possible that you won’t know what you’re looking at. For example, most everyone knows to avoid formaldehyde, but manufactures can legally use over 30 different trade names for formaldehyde, such as:
• Formalin
• Quaternium-15
• Methanal
• Methyl Aldehyde
• Methylene Oxide
• Oxymethylene
• Bfv
• Fannoform
• Formol
• Fyde
• Karsan
• Methaldehyde
• Formalith
• Methylene Glycol
• Ivalon
• Oxomethane

[1] http://www.ncbi.nlm.nih.gov/pubmed/18651574

(2)  Rehorek, A and Plum, A; Characterization of sulfonated azo dyes and aromatic amines by pyrolysis gas chromatography/mass spectrometry; Analitical and Bioanalytical Chemistry, Aug 2007; 388(8): 1653-62.

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Enzymes in textile processing

2 12 2011

Humankind has used enzymes for thousands of years to carry out important chemical reactions for making products such as cheese, beer, and wine. Bread and yogurt also owe their flavor and texture to a range of enzyme producing organisms that were domesticated many years ago.

In the textile industry, one of the first areas which enzyme research opened up was the field of desizing of textiles.  A size is a substance that coats and strengthens the fibers to prevent damage during the weaving process. Size is usually applied to the warp yarn, since this is particularly prone to mechanical strain during weaving.   The size must be removed before a fabric can be bleached and dyed, since it affects the uniformity of wet processing. Previously, in order to remove the size, textiles were treated with acid, alkali or oxidising agents, or soaked in water for several days so that naturally occurring microorganisms could break down the starch. However, both of these methods were difficult to control and sometimes damaged or discoloured the material. But by using enzymes, which are specific for starch, the size can be removed without damaging the fibers.

Enzymes used in textile processing - photo from Novozymes

It represented great progress, therefore, when crude enzyme extracts in the form of malt extract, or later, in the form of pancreas extract, were first used to carry out desizing.  Bacterial amylase derived from Bacillus subtilis  was used for desizing  as early as 1917. Amylase is a hydrolytic enzyme which catalyses the breakdown of dietary starch to short chain sugars, dextrose  and maltose.

Enzymes have been used increasingly in the textile industry since the late 1980s. Many of the enzymes developed in the last 20 years are able to replace chemicals used by mills. The first major breakthrough was when enzymes were introduced for stonewashing jeans in 1987 – because more than one billion pairs of denim jeans require some sort of pre-wash treatment every year. Within a few years, the majority of denim finishing laundries had switched from pumice stones to enzymes.

Today, enzymes are used to  treat and modify fibers, particularly during textile processing and in caring for textiles afterwards.  They are used to enhance the preparation of cotton for weaving, reduce impurities, minimize “pulls” in fabric, or as pre-treatment before dying to reduce rinsing time and improve color quality.  New processing applications have been developed for:

  • Scouring (the process of removing natural waxes, pectins, fats and other impurities from the surface of fibers), which gives a fabric a high and even wet ability so that it can be bleached and dyed successfully. Today, highly alkaline chemicals (such as caustic soda) are used for scouring. These chemicals not only remove the non-cellulosic impurities from the cotton, but also attack the cellulose leading to heavy strength loss and weight loss in the fabric. Furthermore, using these hazardous chemicals result in high COD (chemical oxygen demand) and BOD (biological oxygen demand)  in the waste water. Recently a new enzymatic scouring process known as ‘Bio-Scouring’ is being used in textile wet-processing with which all non-cellulosic components from native cotton are completely or partially removed. After this Bio-Scouring process, the cotton has an intact cellulose structure, with lower weight loss and strength loss. The fabric gives better wetting and penetration properties, making the subsequent bleach process easy and  giving much better dye uptake.
    • One of the newest products, PrimaGreen® EcoScour from Genencor, offers sustainability advantages for eco-scouring in cotton pretreatment, including 30 percent water savings and 60 percent energy savings compared to standard processing. In addition, the mild processing conditions result in improved fabric quality and enhanced color brightness after dyeing.
  • Bleaching – When bleaching cotton, a lot of chemicals, energy and water are part of the process. The company Huntsman has developed a wetter/stabilizer that maximizes the wetting and detergency of the bleaching process and a one-bath caustic neutralizer and peroxide remover in order to shorten the bleaching cycle, reduce energy and water required and deliver more consistent bleaching results. They have developed surfactants that are environmentally friendly (in that they do not contain Alkylphenol ethoxylates), and the system is both Oeko-Tex and GOTS approved.  After fabric or yarn bleaching, residues of hydrogen peroxide are left in the bath, and need to be completely removed prior to the dyeingprocess, using a step called bleach cleanup.  The traditional method is to neutralize the bleach with a reducing agent, but the dose has to be controlled precisely. Incomplete peroxide removal results in poor dyeing with distinct change of color shade and intensity, as well as patchy, inconsistent dye distribution. Enzymes used for bleach clean-up ensure that residual hydrogen peroxide from the bleaching process is removed efficiently – a small dose of catalase breaks hydrogen peroxide into water and oxygen.  This results in cleaner waste water and reduced water consumption.
    • In 2010, a life-cycle assessment was completed comparing PrimaGreen enzymatic bleaching to conventional textile bleaching methods. According to this LCA, if the enzymatic system were to see wide scale global adoption, the potential savings in freshwater consumption could be up to 10 trillion liters of water annually, and greenhouse gas reductions could range from 10-30 million metric tons. (1)
  • Biofinishing or biopolishing (removing fiber fuzz and pills from fabric surface) –  enzymatic biofinishing yields a cleaner surface, softer handfeel, reduces pilling and increases luster;
  • Denim finishing – In the traditional stonewashing process, the blue denim was faded by the abrasive action of pumice stones on the garment surface. Nowadays, denim finishers are using a special cellulase.  Cellulase works by loosening the indigo dye on the denim in a process known as ‘Bio-Stonewashing’. A small dose of enzyme can replace several kilograms of pumice stones. The use of less pumice stones results in less damage to garment, machine and less pumice dust in the laundry environment; in addition, it’s possible to fade denim without risk of damaging the garment.
  • European scientists have just announced a new and environmentally friendly way to produce textile dyes using enzymes from fungi. (2)

Because of the properties of enzymes, they make the textile manufacturing process much more  environmentally benign. (3)   Generally, they:

  1. operate under milder conditions (temperature and pH) than conventional process chemicals – this results in lower energy costs ( up to 120 kg CO2 savings per ton of textile produced) (4) ;
  2. save water – reduction of water usage up to 19,000 liters per ton of textiles bleached;
  3. are an alternative for toxic chemicals, making wastewater easier and cheaper to treat.
  4.  are easy to control;  do not attack the fiber structure with resulting loss of weight, resulting in better quality of material;
  5. better and more uniform affinity for dyes;
  6. contribute to safer working conditions through elimination of chemical treatments during production processes;
  7. are fully biodegradable.

So why is there a ruckus about enzymes being used in textile processing by GOTS and other organic certifying agencies?

(1)   http://primagreen.genencor.com/sustainability/lca_results/

(2)   http://www.just-style.com/news/eco-friendly-textile-dyes-use-enzymes-from-fungi_id112195.aspx

(3)   http://www.textiletodaybd.com/index.php?pid=magazine&id=52

(4)  http://www.europabio.org/sites/default/files/pages/lutz-walter-benefits-from-white-biotechnology-applications-in-the-european-textile-and-clothing-industry.pdf





Certifications: Oeko Tex

28 07 2011

I have an apology to make:  I made a statement last week that turns out to be incorrect, based on experience from years ago.  I said

“it’s not unusual to find a GOTS certification logo on a product – because it’s hard to get, and those who have it certainly want to display the logo.  But the certification may apply only to the organic fibers – the logo itself is not specific as to what is being certified.”

Laurie Lemmlie-Leung, of Sapphire International, Ltd, which is a GOTS certified terry mill, pointed out that in their experience,  “If we do not have an approved “GOTS Product Specification Plan” and transaction certificates showing that all the inputs are also GOTS certified, then we cannot use the GOTS label on the product.”  And that is indeed the case:  a GOTS logo on any product means that all processing up to the final product is GOTS certified.  So if GOTS certified cotton yarn is being sold, it can display the logo.  However, if that yarn is used to weave a fabric in a non-certified facility, the final fabric cannot display the logo.

So when you see a GOTS logo on a product, you can rest assured that the entire supply chain has been certified.

Now, back to discussion of certifications:  Before giving a summary of the main points of each of the certifications which deal with fiber processing (i.e., weaving), it’s important to remember that most of these certification programs are in business – so it costs money to achieve the certification – sometimes it costs a LOT of money.  In addition there is the burden of documentation, which increases administrative costs for the manufacturer.

Cradle to Cradle and GreenGuard can cost quite a bit, so when you look on the web sites to find which products have these certifications,  you see mostly large, well established companies which can afford to absorb the certification costs.  On the GreenGuard website, for example, it lists 1943 individual products, but all 1943 products are manufactured by only 20 large, well-known companies.  Sometimes smaller manufacturers decide not to pay the costs of certification, even though they may be doing everything “by the book”, because they’re operating on a shoestring.  Unfortunately, the many unethical claims make third party certification a requirement.

In addition to certifications, there are many new “green guides” on the internet which purport to list green products.  Some are valiantly trying to make order out of chaos, while others are simply adding to the confusion.  Of these, a basic listing may (or may not) be free, but any additional bells and whistles costs money.  So green products may be specially featured or identified (sometimes as “best”) because the manufacturer has paid for the spotlight.  The same is true of television shows which purport to cover new green products.  We have been approached several times by television programs featuring a well-known personality who would wax eloquently about our fabrics – if only we were to pay the right price.

What does this all mean?  Do your own homework!  Most of these “experts” have no more knowledge than you do.  And again, certifications provide a reliable yardstick to determine quality standards.

The third party certifications which cover textile processing and/or final products which you’ll see most often include:

  • Oeko Tex
  • GreenGuard
  • Cradle 2 Cradle by MBDC
  • Global Organic Textile Standard
  • Global Recycle Standard
  • SMART Sustainable Textile Standard

These are the certifications you’re most likely to run into, and they are very different.  So different, in fact, that we’ll take a few weeks to explore what each one tells us.

This week, we’ll start with one of the oldest certifications:  Oeko Tex.

Oeko Tex is an independent, third party certifier that offers two certifications for textiles:

  1. Oeko-Tex 100 (for products)
  2. Oeko-Tex 1000 (for production sites/factories).

Products satisfying the criteria for Oeko-Tex 100 which are produced in an Oeko-Tex 1000 certified facility may use the Oeko-Tex 100Plus mark, which is simply a combination of the two.

Oeko Tex was founded in 1992, by the Austrian Textile Research Intitute (OTI) and the German Research Institute Hohenstein,  to provide an objective and reliable product label for consumers.  Its aim is to ensure that products posed no risk to health.

Oeko Tex Standard 100

The Oeko-Tex Standard 100 standard is concerned primarily with health and safety of textile products – it tests only the end product.  The processing is not addressed – for example, wastewater treatment is not included.   It is NOT an organic certification and products bearing this mark are not necessarily made from organically grown fibers. (Note:  When you see the logo, make sure that the test number is quoted (No. 11-20489 in the image above)  and the test institute is named (Shirley is the institute which tested the product).)

Textiles considered for this standard are classified into four categories, and each category has different test values for chemicals allowed in the product:

  • Product Class I: Products for Babies – all textile products and materials used to manufacture such textile products for children up to the age of 36 months (leather clothing is excepted)
  • Product Class II: Products with Direct Contact to Skin – worn articles of which a large surface touches the skin (i.e. underwear, shirts, pants)
  • Product Class III: Products without Direct Contact to Skin – articles of which only a small part of their surface touches the skin (i.e. linings, stuffings)

Textile products bearing the Oeko-Tex 100 certification mark:

  • Do not contain allergenic dye-stuffs and dye stuffs that form carcinogenic arylamines.
  • Have been tested for pesticides and chlorinated phenoles.
  • Have been tested for the release of heavy metals under artificial perspiration conditions.
  • Formaldehyde is banned; other aldehyde limits are significantly lower than the required legal limits.
  • Have a skin friendly pH.
  • Are free from chloro-organic carriers.
  • Are free from biologically active finishes.

The certification process includes thorough testing for a lengthy list of chemicals, including lead, antimony, arsenic, phthalates, pesticides, and chlorinated phenols. The official table of limits for tested chemicals may be found on the Oeko-Tex website.  Specifically banned are:

  • AZO dyes
  • Carcinogenic and allergy-inducing dyes
  • Pesticides
  • Chlorinated phenols
  • Chloro-organic benzenes and toluenes
  • Extractable heavy metals
  • Phthalates in baby articles
  • Organotin compounds(TBT and DBT)
  • Emissions of volatile components

Certification may be given to a finished product (such as a shirt), or to individual components (such as yarn, or fabric).

Oeko-Tex Standard 1000

The Oeko-Tex 1000 is a certification for environmentally-friendly textile production.
The goal of the Oeko-Tex 1000 Standard is to be “an evaluation of the environmental performance of textile production sites and products and to document independently that certain environmental measures are undertaken and a certain level achieved.”

The evaluation process includes considerations for:

  • environmental impact: energy consumption, whether materials used are renewable or non-renewable, and the overall impact of the space utilized
  • global impact: use of fossil fuels, use of ozone-depleting chemicals regional impact: VOC’s, water contamination, acidification of soil and water from fossil fuel use, emissions (often from chlorine bleaching)
  • local effects: emissions, workplace contamination, noise, use of dangerous chemical products

The mark is not applied directly to products, but may be used by the production site (for example, on its letterhead and official documents). The “local effects” consideration does NOT include an evaluation of labor practices and is not meant to be an indicator of whether a production site is following fair labor practices.

Oeko-Tex 100Plus

This label may be used on products that have met the Oeko-Tex 100 Standard and are also produced in a facility that meets the Oeko-Tex 1000 Standard.

So, these are the important points to keep in mind when you see the Oeko Tex logo:

  1. Oeko Tex 100 is product specific – they don’t look at processing (i.e., water treatment, workers rights, emissions, sludge), it only means that the finished product (fabric, yarn, clothing, etc.) has limit values for chemicals which are below the threshold limits on the Oeko Tex list, with many specifically prohibited.
  2. Oeko Tex 1000 is site specific, and documents that certain environmental standards are met, but these do not include workers rights issues.
  3. Oeko Tex 100+ means that the site meets environmental standards and the product itself is safe to use.