Bioplastics – are they the answer?

From Peak Energy blog; August 27, 2008

From last week’s blog post, we discussed how bio based plastics do indeed save energy during the production of the polymers, and produce fewer greenhouse gasses during the process.  Yet right off the bat, it could be argued that carbon footprints may be an irrelevant measurement,  because it has been established that plants grow more quickly and are more drought and heat resistant in a CO2 enriched atmosphere!   Many studies have shown that worldwide food production has risen, possibly by as much as 40%, due to the increase in atmospheric CO2 levels.[1] Therefore, it is both ironic and a significant potential problem for biopolymer production if the increased CO2 emissions from human activity were rolled back, causing worldwide plant growth to decline. This in turn would greatly increase the competition for biological sources of food and fuel – with biopolymers coming in last place.[2]  But that’s probably really stretching the point.

The development of bioplastics holds the potential of renewability, biodegradation, and a path away from harmful additives. They are not, however, an automatic panacea.  Although plant-based plastics appeal to green-minded consumers thanks to their renewable origins,  their production carries environmental costs that make them less green than they may seem.  It’s important to remember that bioplastics, just like regular plastics, are synthetic polymers; it’s just that plants are being used instead of oil to obtain the carbon and hydrogen needed for polymerization.

It’s good marketing, but bad honesty, as they say, because there are so many types of plastics and bioplastics that you don’t know what you’re getting in to;  bioplastics are much more complicated than biofuels.  There are about two dozen different ways to create a bioplastic, and each one has different properties and capabilities.

Actually the term “bioplastic” is pretty meaningless, because some bioplastics are actually made from oil – they’re called “bioplastics” because they are biodegradeable.  That causes much confusion because plastics made from oil can be biodegradeable whereas some plant-based  bioplastics are not. So the term bioplastics can refer either to the raw material (biomass) or, in the case of oil-based plastic, to its biodegradability.  The problem with biodegradability and compostability is that there is no agreement as to what that actually means either,  and under what circumstances

You might also see the term “oxo-degradable”.   Oxo-degradables look like plastic, but they are not. It is true that the material falls apart, but that is because it contains metal salts which cause it to disintegrate rapidly into tiny particles. Then you cannot see it anymore, but it is still there, in the ocean too. Just as with conventional plastics, these oxo-degradables release harmful substances when they are broken down.

Let’s re-visit  some of the reasons bioplastics are supposed to be an environmental benefit:

• Because it’s made from plants, which are organic, they’re good for the planet.  Polymer bonds can be created from oil, gas or plant materials. The use of plant materials does not imply that the resulting polymer will be organic or more environmentally friendly. You could make non-biodegradable, toxic plastic out of organic corn!
• Bioplastics are biodegradable. Although made from materials that can biodegrade, the way that material is turned into plastic  makes it difficult (if not impossible) for the materials to naturally break down.  There are bioplastics made from vegetable matter (maize or grass, for example) which are no more biodegradable than any other plastics, says Christiaan Bolck of Food & Biobased Research.[3]  Bioplastics do not universally biodegrade in normal conditions  –  some require special, rare conditions to decompose, such as high heat composting facilities, while others may simply take decades or longer to break down again, mitigating the supposed benefits of using so-called compostable plastics material. There are no independent standards for what even constitutes “biodegradable plastic.”  Sorona makes no claim to break down in the environment; Ingeo is called “compostable” (though it can only be done in industrial high heat composters). Close studies of so-called degradable plastics have shown that some only break down to plastic particles which are so small they can’t be seen  (“out of sight, out of mind”), which are more easily ingested by animals. Indeed, small plastic fragments of this type may also be better able to attract and concentrate pollutants such as DDT and PCB.[4]
• Bioplastics are recyclable. Because bioplastics come in dozens of varieties, there’s no way to make sure you’re getting the right chemicals in the recycling vat – so although some bioplastics are recyclable, the recycling facilities won’t separate them out.  Cargill Natureworks insists that PLA  can in theory be recycled, but in reality it is likely to be confused with polyethylene terephthalate (PET).  In October 2004, a group of recyclers and recycling advocates issued a joint call for Natureworks to stop selling PLA for bottle applications until the recycling questions were addressed.[5]  But the company claims that levels of PLA in the recycling stream are too low to be considered a contaminant.  The process of recycling bioplastics is cumbersome and expensive – they present a real problem for recyclers because they cannot be handled using conventional processes. Special equipment and facilities are often needed. Moreover, if bioplastics commingle with traditional plastics, they contaminate all of the other plastics, which forces waste management companies to reject batches of otherwise recyclable materials.
• Bioplastics are non-toxic.  Because they’re not made from toxic inputs (as are oil based plastics), bioplastics have the reputation for being non toxic.  But we’re beginning to see the same old toxic chemicals produced from a different (plant-based) source of carbon. Example:  Solvay’s bio-based PVC uses phthalates,  requires chlorine during production, and produces dioxins during manufacture, recycling and disposal. As one research group commissioned by the European Bioplastics Association was forced to admit, with regard to PVC,  “The use of bio-based ethylene is …  unlikely to reduce the environmental impact of PVC with respect to its toxicity potential.[6]

The arguments against supporting bioplastics include the fact that they are corporate owned, they compete with food, they bolster industrial agriculture and lead us deeper into genetic engineering, synthetic biology and nanotechnology.  I am not with those who think we shouldn’t go there, because we sorely need scientific inquiry  and eventually we might even get it right.  But, for example, today’s industrial agriculture is not, in my opinion, sustainable, and the genetic engineering we’re doing is market driven with no altruistic motive. 

If properly designed, biodegradable plastics have the potential to become a much-preferred alternative to conventional plastics. The Sustainable Biomaterials Collaborative (SBC)[7] is a coalition of organizations that advances the introduction and use of biobased products. They seek to replace dependence on materials made from harmful fossil fuels with a new generation of materials made from plants – but the shift they propose is more than simply a change of materials.  They promote (according to their website): sustainability standards, practical tools, and effective policies to drive and shape the emerging markets for these products.  They also refer to “sustainable bioplastics” rather than simply “bioplastics”.  In order to be a better choice, these sustainable bioplastics must be:

• Derived from non-food, non-GMO source materials – like algae rather than GMO corn, or from sustainably grown and harvested cropland or forests;
• Safe for the environment during use;
• Truly compostable and biodegradable;
• Free of toxic chemicals during the manufacturing and recycling process;
• Manufactured without hazardous inputs and impacts (water, land and chemical use are considerations);
• Recyclable in a cradle-to-cradle cycle.

Currently, manufacturers are not responsible for the end-life of their products. Once an item leaves their factories, it’s no longer the company’s problem. Therefore, we don’t have a system by which adopters of these new bioplastics would be responsible for recovering, composting, recycling, or doing whatever needs to be done with them after use. Regarding toxicity, the same broken and ineffective regulatory system is in charge of approving bioplastics for food use, and there is no reason to assume that these won’t raise just as many health concerns as conventional plastics have. Yet again, it will be an uphill battle to ban those that turn out to be dangerous.

A study published in Environmental Science & Technology traces the full impact of plastic production all the way back to its source for several types of plastics.[8]   Study author Amy Landis of the University of Pittsburgh says, “The main concern for us is that these plant-derived products have a green stamp on them just because they’re derived from biomass.  It’s not true that they should be considered sustainable. Just because they’re plants doesn’t mean they’re green.”

The researchers found that while making bioplastics requires less fossil fuel and has a lower impact on global warming, they have higher impacts for eutrophication, eco-toxicity and production of human carcinogens.  These impacts came largely from fertilizer use, pesticide use and conversion of lands to agricultural fields, along with processing the bio-feedstocks into plastics, the authors reported.

According to the study, polypropylene topped the team’s list as having the least life-cycle impact, while PVC and PET (polyethylene terephthalate) were ranked as having the highest life-cycle impact.

But as the Plastic Pollution Coalition tells us, it’s not so much changing the material itself that needs changing – it’s our uses of the stuff itself.  We are the problem:   If we continue to buy single-use disposable objects such as plastic bottles and plastic bags, with almost 7 billion people on the planet, our throwaway culture will continue to harm the environment, no matter what it’s made of.

The Surfrider Foundation

The Surfrider Foundation has a list of ten easy things you can do to keep plastics out of our environment:

1. Choose to reuse when it comes to  shopping bags and bottled water.  Cloth bags and metal or glass reusable  bottles are available locally at great prices.
2. Refuse single-serving packaging, excess  packaging, straws and other ‘disposable’ plastics.  Carry reusable utensils in your purse, backpack or car to use at bbq’s, potlucks or take-out  restaurants.
3. Reduce everyday plastics such as sandwich bags and juice cartons by replacing them with a reusable lunch bag/box that includes a thermos.
4. Bring your to-go mug with you to the coffee shop, smoothie shop or restaurants that let you use them. A great  way to reduce lids, plastic cups and/or plastic-lined cups.
5. Go digital! No need for plastic cds,  dvds and jewel cases when you can buy your music and videos online.
6. Seek out alternatives to the plastic  items that you rely on.
7. Recycle. If you must use plastic, try to choose #1 (PETE) or #2 (HDPE), which are the most commonly recycled      plastics. Avoid plastic bags and polystyrene foam as both typically have very low recycling rates.
8. Volunteer at a beach cleanup. Surfrider Foundation Chapters often hold cleanups monthly or more frequently.
9. Support plastic bag bans, polystyrene  foam bans and bottle recycling bills.
10. Spread the word. Talk to your family and friends about why it is important to Rise Above Plastics!

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[1] See for example: Idso, Craig, “Estimates of Global Food Production in the year 2050”, Center for the Study of Carbon dioxide and Global Change, 2011  AND  Wittwer, Sylvan, “Rising Carbon Dioxide is Great for Plants”, Policy Review, 1992  AND  http://www.ciesin.org/docs/004-038/004-038a.html

[2] D. B. Lobell and C. B. Field, Global scale climate-crop yield relationships and the impacts of recent warming, Env. Res. Letters 2, pp. 1–7, 2007 AND L. H. Ziska and J. A. Bunce, Predicting the impact of changing CO2 on crop yields: some thoughts on food, New Phytologist 175, pp. 607–618, 2007.

[3] Sikkema, Albert, “What we Don’t Know About Bioplastics”, Resource, December 2011; http://resource.wur.nl/en/wetenschap/detail/what_we_dont_know_about_bioplastics

[4] Chandler Slavin, “Bio-based resin report!” Recyclable Packaging Blog May 19, 2010 online at http://recyclablepackaging.wordpress.com/2010/05/19/bio-based-resin-report

[5] http://www.newint.org/features/2008/09/01/plastic-plants/

[6] L. Shen, “Product Overview and Market Projection of Emerging Bio- Based Plastics,” PRO-BIP 2009, Final Report, June 2009

[7] http://www.sustainablebiomaterials.org/index.php

[8] http://news.discovery.com/earth/bioplastic-plant-plastic-environment.html

Bioplastics

The first plastic garbage bag was invented by Harry Waslyk in 1950.

1950!  Mr. Waslyk could not have predicted how much havoc his plastic child would wreck in a mere 62 years.[1]

We’ve all seen the pictures of birds stomachs filled with plastic detritus and read about the Great Pacific Gyre, but I just read a new twist to that story:    the Emirates News Agency reported that decomposed remains of camels in the desert region of the United Arab Emirates revealed that 50% of the camels died from swallowing and choking on plastic bags.  “Rocks of calcified plastic weighing up to 60 kilograms are found in camel stomachs every day,” said Dr. Ulrich Wernery, Scientific Director, Central Veterinary Research Laboratory in Dubai, whose clinic conducts hundreds of post-mortems on camels, gazelles, sheep and cows in the UAE.  He adds that one in two camels die from plastic.[2]

Plastic has become so ubiquitous, in fact, that plastics are among the debris orbiting our planet. Unfortunately, our wildlife and domestic animals are paying the price now; I think we ourselves will see changes in future generations.

It’s no wonder we’re scrambling to find alternatives to plastic, and one hot topic in the research area is that of bioplastics.

Bioplastics are made (usually) from plant materials.  Enzymes are used to break starch in the plant into glucose, which is fermented and made into lactic acid.  This lactic acid is polymerized and converted into a plastic called polylactic acid (PLA), which can be used in the manufacture of products  ( PLA is about 20% more expensive than petroleum-based plastic)  or into a plastic  called polyhydroxyalkanoate, or PHA (PHA biodegrades more easily but is more than double the price of regular plastic).

The bioplastic market is expanding rapidly and by 2030, according to some estimates, could account for 10% of the total plastics market.   In the world of fabrics and furnishings, the new biotech products which are being heavily promoted are Ingeo and Sorona, both PLA based fibers with a growing share of the fabric market; and soy-based foam for upholstery.    Toray Industries has announced that they will have the first functional performance nylon and polyester textiles based on biomass ready for the 2013/14 season.  They are 100% bio-based fabrics [3] based on the castor plant, which is very robust, growing in dry farming areas and requiring significantly fewer pesticides and herbicides than other crops.

So it’s no wonder that there has been much discussion about bioplastics, and about whether there are ecological advantages to using biomass instead of oil.

The arguments in favor of bioplastics are:

• They are good for the environment because there is no harm done to the earth when recovering fossil fuels. Also, in this process there are very few greenhouse gas and harmful carbon emissions. Regular plastics need oil for their manufacturing, which pollutes the environment.
• They require less energy to produce than petroleum-based plastics.
• They are recyclable.
• They are non toxic.
• They reduce dependence on foreign oil.
• They are made from renewable resources.

These arguments sound pretty good – until you begin to dig  and find out that once again, nothing is ever as simple as it seems.

Regarding the first two arguments (they are good for the environment because they produce significantly fewer CO2 emissions and less energy) -  there have not been many studies which support  this argument until recently.  Recently,  several  studies have been published which seems to support that  this is indeed the case:

1. Ramani Narayan of Michigan State University found that “the results for the use of fossil energy resources and GHG emissions are more favorable for most bio based polymers than for oil based. As an exception, landfilling of biodegradable polymers can result in methane emissions (unless landfill gas is captured) which may make the system unattractive in terms of reducing greenhouse gas emissions.”[4]
2. University of Pittsburgh researchers did an LCA on the environmental impacts of both petroleum and bio derived plastics, assessing them using metrics which included  economy, mass from renewable sources, biodegradability, percent recycled, distance of furthest feedstock, price, life cycle health hazards and life cycle energy use. They found that  biopolymers are the more eco-friendly material in terms of energy use and emissions created.  However, they also concluded that traditional plastics can actually be less environmentally taxing to produce when taking into account such things as acidification, carcinogens, ecotoxicity, eutrophication, global warming, smog, fossil fuel depletion, and ozone depletion.[5]
3. A study done by the nova-Institut GmbH on behalf of Proganic GmbH & Co.[6]showed unambiguously positive eco advantages (in terms of energy use and CO2 emissions) for bio based polymers PLA and PHA/PHB over petrochemical based plastics.  According to the report, “the emission of greenhouse gases and also the use of fossil raw materials are definitely diminished. Therefore the substitution of petrochemical plastics with bio-based plastics yields positive impacts in the categories of climate change and depletion of fossil resources.”  The results include:
   1. Greenhouse gas emissions of bio-based plastics amount to less than 3 KG of CO2 equivalents per KG of plastic, less than that of petrochemical based plastics which produce an average of 6 KG of CO2 equivalents per KG of plastic..
   2. the production of bio-based polymers, in comparison to all petrochemical plastics examined, leads to savings in fossil resources. The biggest savings potential can be found in comparison with polycarbonate (PC). The average savings potential in the production of PLA amounts to 56 ± 13 megajoules per kilogram of plastics here.
   3. The production of bio-based polymers in comparison with the production of petrochemical plastics in most cases also leads to greenhouse gas emission savings. The biggest greenhouse gas emission savings can be found again when comparing bio-based polymers to polycarbonate (PC). For PLA, the average savings potential in this case amounts to 4.7 ± 1.5 kilograms of CO2 equivalents per kilogram of plastics. For PHA, the average savings potential in this case amounts to 5.8 ± 2.7 kilograms of CO2 equivalents per kilogram of plastics. In comparison with PET and Polystyrene (PS), considerable savings potentials ranging between 2.5 and 4.2 kilograms of CO2 equivalents per kilogram of plastics are to be found in the production of bio-based polymers. The lowest savings potential are to be found when comparing bio-based polymers with polypropylene (PP).

So I will accept the arguments that biobased plastics produce fewer  greenhouse gases and harmful carbon emissions and require less energy to produce than petroleum-based plastics .  They also certainly reduce our dependence on foreign oil.

But are they better for the environment?  Are they recyclable or biodegradeable?  Are they safe?  Are plastics producers aware of the impact of promoting bioplastics as a replacement for plastics? We think that  bioplastics are useful for certain purposes, such as medical sutures or strewing foil for mulching in agriculture – but as a replacement for all plastics?

Next week we’ll take a look at the arguments against bioplastics.

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[1] Laylin, Tafline, “Half of UAE’s Falaj Mualla Camels Choked on Plastic Bags”, Green Prophet blog, June 11, 2010.

http://www.greenprophet.com/2010/06/camels-choke-on-plastic/

[2] Ibid.

[3] http://www.ecotextile.com/2012020811377/materials-production-news/biomass-fabrics-for-sportswear-within-two-years.html

[4] Narayan, Ramani, “Review and Analysis of Bio-based Product LCA’s”, Department of Chemical Engineering & Materials Science, Michigan State University, East Lansing, MI 48824

[5] Tabone, Michaelangelo D., et al; “Sustainability Metrics: Life Cycle Assessment and Green Design in Polymers”, Enviornmental Science and Technology, September 2, 2010.

[6]http://www.google.com/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=1&ved=0CCEQFjAA&url=http%3A%2F%2Fwww.nova-institut.de%2Fdownload%2FMeta-LCA%2520PR&ei=ihJ-T_C7K5HRiAKlrIzlDQ&usg=AFQjCNFQ9rxS2G0YQ3dlrlsskwoXnFbCmQ

Outdoor fabrics

We love being outdoors. I’ve been told that the most popular outdoor activity in the U.S.A is picnicking.  I would think barbeque must be a close second.  So we love fabrics that we can use outdoors  – you know the ones that resist fading, are stain resistant and can be cleaned with mild soap and water?  They don’t fade or degrade.  Perfect!

Let’s look at America’s most popular outdoor fabric, Sunbrella, which their website claims is recognized as “a fabric with a conscience”, because, as they claim:

• all Sunbrella fabrics are fully recyclable;
• they require no dyeing that produces wastewater;
• and they have received the GREENGUARD and Skin Cancer Foundation certifications.

Before we show why we think these are all claims which exemplify different facets of what Terra Choice calls the “Six Sins of Greenwashing”, let’s first look at the stuff Sunbrella is made of.

Sunbrella is, as their website says, a 100% solution dyed acrylic fabric.   Solution dyeing is simply mixing the dyestuff into the melted polymer.  So unlike dyeing that penetrates a fiber,  this method means that the color is inherent in the fiber, and there is no dye or water waste.  This is a good method of dyeing – but that’s not the issue  – the real issue is what the fabrics are made of.

The key ingredient of acrylic fiber is acrylonitrile, (also called vinyl cyanide).   Acrylic manufacturing involves highly toxic substances which require careful storage, handling, and disposal. The polymerization process can result in an explosion if not monitored properly.  It also produces toxic fumes. Recent legislation requires that the polymerization process be carried out in a closed environment and that the fumes be cleaned, captured, or otherwise neutralized before discharge to the atmosphere – because the burning of acrylic releases fumes of hydrogen cyanide and oxides of nitrogen.

The International Agency for Research on Cancer (IARC) concluded that there is inadequate evidence in humans for the carcinogenicity of acrylonitrile, but classified it as a Class 2B carcinogen (possibly carcinogenic).   Acrylonitrile increases cancer in high dose tests in male and female rats and mice. ⁽¹⁾    A recent report which was published in Occupational and Environmental Medicine  found that women who work in textile factories which produce acrylic fabrics have seven times the risk of developing breast cancer than the normal population.(2)

According to the Centers for Disease Control and Prevention, acrylonitrile enters our bodies through skin absorption, as well as inhalation and ingestion.

Acrylic is not easily recycled nor is it readily biodegradable. It is considered a group 7 plastic among recycled plastics and is not collected for recycling in most communities. Large pieces can be reformed into other useful objects if they have not suffered too much stress, crazing, or cracking, but this accounts for only a very small portion of the acrylic plastic waste. In a landfill, acrylic plastics, like many other plastics, are not readily biodegradable. Some acrylic plastics are highly flammable and must be protected from sources of combustion.

Now that you know what Sunbrella’s made of, let’s look at their claims:

• All Sunbrella fabrics are fully recyclable – If you check the website, Sunbrella has a proprietary recycling program, which means they will pick up your old Sunbrella.  Why do they do this?  Because the local municipalities do not accept acrylic fabric nor do most plastic recycling companies.  It’s admirable that Sunbrella has put this program into place, but we don’t really know that they actually re-purpose the old fabric rather than simply cart it to the landfill, do we?
• Sunbrella fabrics require no dyeing that produces wastewater  - because it’s solution dyed, so therefore this is, well if not exactly a red herring, certainly irrelevant to the fact that the fabric is made from acrylic.
• Sunbrella fabrics have received the GREENGUARD and Skin Cancer Foundation certifications.
  • Sunbrella fabrics have been certified by GreenGuard Children and Schools because the chemicals used in acrylic production are bound in the polymer – in other words, they do not evaporate. So Sunbrella fabrics do not contribute to poor air quality, (you won’t be breathing them in), but there is no guarantee that you won’t absorb them through your skin. And you would be supporting the production of more acrylic, the production of which is not a pretty thing.
  • With regard to the Skin Cancer Foundation – the certification seems to be based on the fact that Sunbrella fabrics block the sun, which prevents skin cancer, rather than anything inherently beneficial in the fabric itself – because the certification is not valid for any Sunbrella fabric which is sheer or transparent.  So another red herring.

Now that you know what Sunbrella is made of, do you really want convenience at such a great cost?

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(1) Hagman, L, “How confident can we be that acrylonitrile is not a human carcinogen?”, Scandanavian Journal of Work, Environment and Health, 2001;27(1):1-4 .

[2] Occupational and Environmental Medicine 2010, 67:263-269 doi: 10.1136/oem.2009.049817 (abstract: http://oem.bmj.com/content/67/4/263.abstract) SEE ALSO: http://www.breastcancer.org/risk/new_research/20100401b.jsp AND http://www.medpagetoday.com/Oncology/BreastCancer/19321

Eucalyptus fiber by any other name

Fibers are divided into three main categories:

• Natural – like flax, wool, silk and cotton
• Manufactured – made from cellulose or protein
• Synthetic – made from synthetic chemicals

The difference between “manufactured” and “synthetic” fibers is that the manufactured fibers are derived from naturally-occurring cellulose or protein, while synthetic fibers are not.  And  manufactured fibers are unlike  natural fibers because they require extensive processing (or at least more than is required by natural fibers) to become the finished product.  The category of “manufactured” fibers is often called “regenerated cellulose” fibers.  Cellulose is a carbohydrate and the chief component in the walls of plants.

Rayon is the oldest manufactured fiber, having been in production since the 1880s in France, where it was originally developed as a cheap alternative to silk.   Most rayon production begins with wood pulp, though any plant material with long molecular chains is suitable.

There are several chemical and manufacturing techniques to make rayon, but the most common method is known as the viscose process. In the viscose process, cellulose is treated with caustic soda (aka: sodium hydroxide) and carbon disulfide, converting it into a gold, highly viscous  liquid about the color and consistency of honey.  This substance gives its name to the manufacturing process, called the viscose process.

The viscous fluid is allowed to age, breaking down the cellulose structures further to produce an even slurry, and is then filtered to remove impurities.  Then the mixture is forced through fine holes, called a spinerette, directly into a chemical bath where it hardens into fine strands. When washed and bleached these strands become rayon yarn.

Although the viscose process of making rayon from wood or cotton has been around for a long time, it wasn’t until 2003 that a method was devised for using bamboo for this process.(3)  Suddenly, bamboo was the darling of marketers, and the FTC had to step in to remind manufacturers to label their products as “bamboo viscose” rather than simply bamboo.

Now we hear about fabrics made from  eucalyptus, or soy.  But it’s the same story – the fibers are created using the viscose process.  Because the FTC did not specifically name these two substances in their proclamation regarding bamboo,   marketers can claim fabrics are  “made from eucalyptus”.    The reality is that the viscose process can produce fibers from any cellulose or protein source – chicken feathers, milk and even bacteria have been used (rayon comes specifically from wood or cotton).  But those inputs are not nearly as exciting to the marketers as eucalyptus or soy, so nobody has been advertising fibers made from bacteria.

After the brouhaha about bamboo viscose hit the press, many people did a quick scan of viscose and declared it “unsafe” for the environment.  The reason the viscose process is thought to be detrimental to the environment is based on the process chemicals used. Though sodium hydroxide is routinely used in the processing of organic cotton, and is approved by the Global Organic Textile Standard (GOTS), carbon disulfide can cause nervous system damage with chronic exposure.  And that “chemical bath” to harden the threads?  Sulfuric acid.  But these chemicals do not remain as a residue on the fibers – the proof of this is that almost all of the viscose produced can be (and often is) Oeko Tex certified (which certifies that the finished fiber has been tested for any chemicals which may be harmful to a person’s health and contains no trace of these chemicals.)

The environmental burden comes in disposing of these process chemicals: the sodium hydroxide (though not harmful to humans) is nevertheless harmful to the environment if dumped into our rivers as untreated effluent. Same with carbon disulfide  and, certainly, sulfuric acid.  And there are emissions of these chemicals as well, which contribute to greenhouse gasses.  And the reason that these fibers can be Oeko Tex certified:  Oeko Tex certifies only the final product, i.e.,the fibers or the fabric.  They do not look at the production process, which is where the majority of the environmental burden is found.  And then of course there is the weaving of these viscose fibers into fabric – if done conventionally, the environmental burden is devastating (in terms of chemical and water use) and the fabric itself probably contains many chemicals known to be harmful to our health.

Certainly the standard viscose production process is definitely NOT environmentally friendly, but then there is Tencel ® and Modal ®.   These fibers are manufactured by the Austrian company Lenzing, which  advertises its environmentally friendly production processes, based on closed loop systems.  Lyocell is the generic name for the fibers produced by Lenzing, which are not produced by the traditional viscose process but rather by solvent spinning.

According to Lenzing:

• There is an almost complete recovery of the solvent, which both minimizes emissions and conserves resources.  Lenzing uses  a new non-toxic solvent (amine oxide) and the cellulose is dissolved in N-Methylmorpholine N-oxide rather than sulfuric acid. Water is also evaporated, and the resulting solution filtered and extruded as filaments through spinnerets into an aqueous bath. Over 99% of the solvent can washed from the fiber and purified for re-use. The water is also recycled.
•  The by products of production, such as acetic acid, xylose and sodium sulphate are key ingredients in the food and glass industry. Remaining materials are used as energy for the Lenzing process.
• Tencel ® is made from eucalyptus, which is grown on marginal land unsuitable for food crops; these trees are grown with a minimum of water and are grown using sustainable forestry initiatives.
• The final fibers are biodegradable and can decompose in soil burial or in waste water treatment plants.

So Lenzing fibers can be considered a good choice if you’re looking for a sustainable fiber – in fact there is a movement to have Lenzing Tencel® eligible for GOTS certification, which we support, because the production of these fibers conforms with the spirit of GOTS.  They already have the EU Flower certification.

But Lenzing does not make fabrics – it sells yarns to mills and others which use the yarns to make fabric and other goods.

So  we’re back to the beginning again, because people totally forget about the environmental impact in the weaving of fibers into fabric, where the water and chemical use is very high –  if done conventionally, the environmental burden is devastating  and the finished fabric itself probably contains many chemicals which are outlawed in other products.

It’s critically important to look at both the fiber as well as the weaving in order to make a good choice.

Synthetic fibers and our oceans

First we heard about the world’s biggest garbage dump – made up of the detritus of our time: plastic bottles, plastic bags, DVD cases  – floating in our ocean. About 44 percent of all seabirds eat plastic, apparently by mistake, sometimes with fatal effects. And many marine species are affected by plastic garbage—animals are known to swallow plastic bags, which resemble jellyfish in mid-ocean, for example—according to a 2008 study in the journal Environmental Research by oceanographer and chemist Charles Moore, of the Algalita Marine Research Foundation.[1]

Just as soon as we’ve had time to digest this news, we discover that the more improbable impact to the oceans from plastic comes from microscopic particles of plastic:   In fact, the mass of plastic the size of Texas often said to exist in the North Pacific is a myth, according to filmmaker Craig Leeson, who is producing a documentary (backed by David Attenborough and the UK-based Plastic Oceans Foundation)  on the spread of plastics in our oceans.   Instead, particles of plastic lurk in our oceans invisibly, in seemingly clear water.

“If you trawl for it with these special nets that they’ve developed, you come back with this glutinous mass — it’s microplastics that are in the water along with the plankton,” he said. “The problem is that it’s being mistaken for food and being eaten by plankton eaters, who are then eaten by bigger fish, and so it goes on, and it ends up on our dinner tables.”[2]

Charles Moore  has found that in some areas, plastic outweighs zooplankton – the ocean’s food base.[3]

It’s not just in the water:  Dr. Mark Browne, University College Dublin, and several colleagues gathered sand samples from 18 beaches on six continents for analysis. It turns out that every beach tested contained microplastics  (particles about the size of a piece of long grain of rice or smaller).  Charles Moore carries a bag of sand from a beach in Hawaii which he had analyzed – and found that it was 90% plastic.

Studies show that this contamination is getting worse – and link it with health conditions in humans including cancer, diabetes and immune disruption.

So how does this tie into our blog topic of textile issues?

It turns out that 80% of the microplastic found in the samples which the scientists collected on the beaches was fibrous:  polyester, acrylic and polyamides (nylon) fibers.  And the scientists are pretty sure the fibers come from fabric.

According to Science:  “Not a single beach was free of the colorful synthetic lint. Each cup of sand contained at least two fibers and as many as 31. The most contaminated samples came from areas with the highest population density, suggesting cities were an important source of the lint.”[4]

In order to test their idea that sewer discharges were the source of these the plastic discharges, the team worked with a local authority in New South Wales, Australia, and found that their suspicions were correct.  Sewage treatment does not remove the fibers.  But where do the fibers enter the waste stream?

Dr Browne and his colleagueProfessor Richard Thompson from the University of Plymouth carried out a number of experiments to see what fibers were contained in the water discharge from washing machines.

According to a study published in September’s Environmental Science and Technology [5], nearly 2,000 polyester fibers can shake loose from a single piece of clothing in the wash.

“It may not sound like an awful lot, but if that is from a single item from a single wash, it shows how things can build up.” [6]

“It suggests to us that a large proportion of the fibres we were finding in the environment, in the strongest evidence yet, was derived from sewerage as a consequence from washing clothes.”

On Cyber Monday last year, outdoor retailer Patagonia took out a full-page ad in The New York Times asking readers to “buy less and to reflect before you spend a dime.” Beside a photo of their iconic R2® fleece jacket, the headline read: “Don’t Buy This Jacket.”

We fully support Patagonia’s message that we should all pause before consuming anything – our consumption patterns are, after all, what got us into this mess.  “But there might be another reason to take a pass on that jacket besides Patagonia’s confession that the process of creating the R2® Jacket leaves behind “two-thirds of its weight in waste” on its way to their Reno warehouse — it turns out that tossing the jacket in the washer causes it to leave behind something else entirely — thousands of tiny plastic threads.” [7]

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[1] http://news.nationalgeographic.com/news/2009/08/090820-plastic-decomposes-oceans-seas.html

[2] http://www.mnn.com/lifestyle/arts-culture/stories/filmmaker-sounds-alarm-over-ocean-of-plastic

[3] http://www.voanews.com/english/news/environment/Plastics-in-Oceans-More-Damaging-Than-Climate-Change–133190248.html

[4] http://grist.org/living/2011-12-07-how-microplastics-cause-macro-problems-for-the-ocean/

[5] Browne, Mark et al; “Accumulation of Microplstic on Shorelines Worldwide: Sources and Sinks”, Environmental Science and Technology, 2011, 45(21), pp 9175-9179.

[6] http://quierosaber.wordpress.com/tag/environmental-science-and-technology/

[7] http://grist.org/living/2011-12-07-how-microplastics-cause-macro-problems-for-the-ocean/

Bisphenol A in textile processing?

If you’ve bought baby bottles or water bottles recently, I’m sure you’ve seen a prominent “BPA Free” sign on the container.

BPA stands for Bisphenol A, a chemical often used to make clear, polycarbonate plastics (like water and baby bottles and also eyeglass lenses, medical devices, CDs and DVDs, cell phones and computers).  And though it has been formally declared a hazard to human health in Canada and banned in baby bottles in both Canada as well as the EU,  U.S. watchdog agencies have wildly differing views of BPA:  The National Toxicology Program (NTP) reported “some concern” that BPA harms the brain and reproductive system, especially in babies and fetuses.  The Food and Drug Administration declared that “at current levels of exposure” BPA is safe.

But consider this:  Of  the more than 100 independently funded experiments on BPA, about 90% have found evidence of adverse health effects at levels similar to human exposure. On the other hand, every single industry-funded study ever conducted — 14 in all — has found no such effects.  David Case made the argument in the February 1, 2009 issue of Fast Company that this is a story about protecting a multibillion-dollar market from deregulation.  But that’s beside the point  which is:    nobody disputes the fact that people are constantly exposed to BPAs and babies are most at risk.  It’s also undisputed that BPA mimics the female sex hormone estrogen, and that some synthetic estrogens can cause infertility and cancer.  If you’d like to read more about this click here.

Bisphenol A is now deeply imbedded in the products of modern consumer society.  This is important because it’s used in so many modern products (making it pretty much ubiquitous), and because it is extremely potent in disrupting fetal development. BPA contamination is also widespread in the environment. For example, BPA can be measured in rivers and estuaries at concentrations that range from under 5 to over 1900 nanograms/liter.(1)

What this all means is that most of  us live our lives in close proximity to bisphenol A.

Because it’s used to make plastic hard, I never thought it would have a place in the textile industry.  So it was with some concern that I came across articles which explain the use of bisphenol A in the manufacturing of synthetic fibers.

Producing synthetic fibers and yarns is almost impossible without applying a processing aid to the fibers during the extrusion and spinning processes.   The fibers and yarns are frequently in contact with hot surfaces, or they pass through hot ovens.  In order to withstand these extreme conditions, the yarns and fibers have processing aids or finishes applied.    This applied processing aid or ‘finish’, in addition to helping the yarns withstand extreme temperatures, also  reduces static electricity, fiber-fiber and metal-fiber friction, provides integrity to the filaments,  and altogether eases the manufacturing processes.

But because modern manufacturing equipment runs at higher speeds and subsequently at higher temperatures, the finish degrades in the high temperatures – yielding lower quality fibers -  and generates unwanted decomposition products.  These byproducts can be in the form of:

1. Toxic and nontoxic gases which have environmental and safety issues;
2. Liquids, which leave a sticky residue on the yarns,
3. Or they may form a solid varnish on hot surfaces that is very difficult to remove; the presence of the varnish interferes with continuous, efficient production leading to economic losses due to equipment shutdown and product failure.

To overcome the problems caused by the degradation of finishes, several additives are introduced to prevent or delay the reactions of oxidation and degradation.  Several classes of antioxidants are typically used as these additives in these finishes.

In a study sponsored by the National Textile Center, a research consortium of eight universities, three North Carolina State University professors investigated the thermal stability of textiles, specifically with respect to the antioxidants used in the finishes.  They investigated four different antioxidants – one of which is based on Bisphenol A. (2)

So I got interested, and began a bit of poking around for other mentions of Bisphenol A in the textile industry. I found two scientific references to use of bisphenol A in the production of  polyester fabrics.  Both reported similar use of Bisphenol A as this quote,  which states:  “ a woven polyester fabric was … finished with an aqueous compound  containing 5% polyethylene glycol bisphenol A ether diacrylate for 30 min at 60° to give a hygroscopic, antistatic fabric with good washfastness.” (3)

I found that Bisphenol A is used  in the production of flame retardants, and as an intermediate in the manufacture of polymers, fungicides, antioxidants (mentioned above), and dyes.   Because it is often used as an intermediate it’s hard to pin down, and manufacturers keep their ingredients trade secrets so we often will not know – unless somebody funds a study which is published.

I have not seen any studies which report finding Bisphenol A in a finished fabric, so this may be a tempest in a teacup.  But isn’t it worth noting that this chemical, which has been found in the blood of 95% of all Americans, and which some say may be the “new lead”, can exist in products in which we previously never would have thought to look?

(1)  http://www.ourstolenfuture.org/newscience/oncompounds/bisphenola/bpauses.htm

(2) Grant, Christine; Hauser, Peter; Oxenham, William, “Improving the Thermal Stability of Textile Processing Aids”,  www.ntcresearch.org/pdf-rpts/AnRp04/C01-NS08-A4.pdf

(3)  http://www.lookchem.com/cas-644/64401-02-1.html?countryid=0

Polyester and our health

Polyester is a very popular fabric choice – it is, in fact, the most popular of all the synthetics.  Because it can often have a synthetic feel, it is often blended with natural fibers, to get the benefit of natural fibers which breathe and feel good next to the skin, coupled with polyester’s durability, water repellence and wrinkle resistance.  Most sheets sold in the United States, for instance, are cotton/poly blends.

It is also used in the manufacture of all kinds of clothing and sportswear – not to mention diapers, sanitary pads, mattresses, upholstery, curtains  and carpet. If you look at labels, you might be surprised just how many products in your life are made from polyester fibers.

So what is this polyester that we live intimately with each day?

At this point, I think it would be good to have a basic primer on polyester production, and I’ve unabashedly lifted a great discussion from Marc Pehkonen and Lori Taylor, writing in their website diaperpin.com:

Basic polymer chemistry isn’t too complicated, but for most people the manufacture of the plastics that surround us is a mystery, which no doubt suits the chemical producers very well. A working knowledge of the principles involved here will
make us more informed users.

Polyester is only one compound in a class of petroleum-derived substances known as polymers. Thus, polyester (in common with most polymers) begins its life in our time as crude oil. Crude oil is a cocktail of components that can be separated by industrial distillation. Gasoline is one of these components, and the precursors of polymers such as polyethylene are also present.

Polymers are made by chemically reacting a lot of little molecules together to make one long molecule, like a string of beads. The little molecules are called monomers and the long molecules are called polymers.

Like this:

O + O + O + . . . makes OOOOOOOOOOOOOOOO

Depending on which polymer is required, different monomers are chosen. Ethylene, the monomer for polyethylene, is obtained directly from the distillation of crude oil; other monomers have to be synthesized from more complex petroleum derivatives, and the path to these monomers can be several steps long. The path for polyester, which is made by reacting ethylene glycol and terephthalic acid, is shown below. Key properties of the intermediate materials are also shown.

The polymers themselves are theoretically quite unreactive and therefore not particularly harmful, but this is most certainly not true of the monomers. Chemical companies usually make a big deal of how stable and unreactive the polymers are, but that’s not what we should be interested in. We need to ask, what about the monomers? How unreactive are they?

We need to ask these questions because a small proportion of the monomer will never be converted into polymer. It just gets trapped in between the polymer chains, like peas in spaghetti. Over time this unreacted monomer can escape, either by off-gassing into the atmosphere if the initial monomers were volatile, or by dissolving into water if the monomers were soluble. Because these monomers are so toxic, it takes very small quantities to be harmful to humans, so it is important to know about the monomers before you put the polymers next to your skin or in your home. Since your skin is usually moist,
any water-borne monomers will find an easy route into your body.

Polyester is the terminal product in a chain of very reactive and toxic precursors. Most are carcinogens; all are poisonous. And even if none of these chemicals remain entrapped in the final polyester structure (which they most likely do), the manufacturing process requires workers and our environment to be exposed to some or all of the chemicals shown in the flowchart above. There is no doubt that the manufacture of polyester is an environmental and public health burden
that we would be better off without.

What does all of that mean in terms of our health?  Just by looking at one type of cancer, we can see how our lives are being changed by plastic use:

• The connection between plastic and breast cancer was first discovered in 1987 at Tufts Medical School in Boston by
  research scientists Dr. Ana Soto and Dr. Carlos Sonnenschein. In the midst of their experiments on cancer cell growth, endocrine-disrupting chemicals leached from plastic test tubes into the researcher’s laboratory experiment, causing a rampant proliferation of breast cancer cells. Their findings were published in Environmental Health Perspectives (1991)[1].
• Spanish researchers, Fatima and Nicolas Olea, tested metal food cans that were lined with plastic. The cans were also found to be leaching hormone disrupting chemicals in 50% of the cans tested. The levels of contamination were twenty-seven times more than the amount a Stanford team reported was enough to make breast cancer cells proliferate. Reportedly, 85% of the food cans in the United States are lined with plastic. The Oleas reported their findings in Environmental Health Perspectives (1995).[2]
• Commentary published in Environmental Health Perspectives in April 2010 suggested that PET might yield endocrine disruptors under conditions of common use and recommended research on this topic. [3]

These studies support claims that plastics are simply not good for us – prior to 1940, breast cancer was relatively rare; today it affects 1 in 11 women.  We’re not saying that plastics alone are responsible for this increase, but to think that they don’t contribute to it is, we think, willful denial.  After all, gravity existed before Newton’s father planted the apple tree and the world was just as round before Columbus was born.

Polyester fabric is soft, smooth, supple – yet still a plastic.  It contributes to our body burden in ways that we are just beginning to understand.  And because polyester is highly flammable, it is often treated with a flame retardant, increasing the toxic load.  So if you think that you’ve lived this long being exposed to these chemicals and haven’t had a problem, remember that the human body can only withstand so much toxic load - and that the endocrine disrupting chemicals which don’t seem to bother you may be affecting generations to come.

Agin, this is a blog which is supposed to cover topics in textiles:   polyester is by far the most popular fabric in the United States.  Even if made of recycled yarns, the toxic monomers are still the building blocks of the fibers.  And no mention is ever made of the processing chemicals used to dye and finish the polyester fabrics, which as we know contain some of the chemicals which are most damaging to human health.

Why does a specifier make the decision to use polyester – or another synthetic –  when all the data points to this fiber as being detrimental to the health and well being of the occupants?  Why is there not a concerted cry for safe processing chemicals at the very least?

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[1] http://www.bu-eh.org/uploads/Main/Soto%20EDs%20as%20Carcinogens.pdf

[2] http://ehp03.niehs.nih.gov/article/fetchArticle.action?articleURI=info:doi/10.1289/ehp.95103608

[3]  Sax, Leonard, “Polyethylene Terephthalate may Yield Endocrine Disruptors”,
Environmental Health Perspectives, April 2010, 118 (4): 445-448

Pesticide residues in cotton fibers

We’re often asked if there are traces of pesticides in conventionally grown natural fibers – because people make the assumption that if pesticides are used on the plants, then there must be residuals in the fibers.  And because the chemicals used on conventional cotton crops are among the most toxic known, such as aldicarb ( which  can kill a man by just one drop absorbed thru the skin) and endosulfan (thought to be the most important source of fatal poisoning among cotton farmers in West Africa), as well as a host of confirmed carcinogens[1],   that seems a reasonable cause for concern.

But that question misses the whole point, as we’ll explain.

According to the modern agricultural industry,  cotton agriculture uses integrated pest management (IPM) systems to promote cotton’s environmental stance (author’s note:  reduction of costs doesn’t hurt either).

As the result, the use of chemicals on cotton crops is down:  On average “only” 20 lbs. of pesticides are applied to an acre of cotton today – as opposed to about 40 lbs. in the past. 

IPM is a great advance on the part of agriculture to use biological controls.  But 20 lbs. per acre is still a lot of really bad chemicals being used.  So the Bremen Cotton Exchange,[2]  on behalf of the industry, has sponsored a series of tests which were carried out by the Hohehnstein Research Institute  according to Oeko-Tex 100 Standard (also known as Eco Tex).  They tested for 228 possible substances including:

• Formaldehyde
• PCP
• pH Value
• Heavy Metals
• Defoliants

All the test series confirm that the treatment and use of pesticides in cotton production, according to their report,  “does not pose any hazard for the processor of the raw material and none at all for the end consumer.”  This is the industry’s position, based on the test results from their studies.  On the other hand, there are other studies that do find pesticide residues in cotton textiles -  of nine different organochlorine pesticides at levels of 0.5 to 2 mg/kg.[3]  So there seems to be a difference of opinion as to whether there are pesticide residues in the cotton fibers or finished cloth.

But there is not much difference of opinion in the fact that pesticide residues pollute our soils.    Many different studies have found pesticide residues which pollute agriculture soils in various parts of the world. [4]

"Pesticide Residues in Soil & Water from Four Areas of Mali", From Journal of Agricultural, Food & Environmental Sciences, Vol 1, issue 1, 2007

And just recently,  Science News reported that children exposed in the womb to pesticides have lower IQs than do kids with virtually no exposure.  According to Science News:

“Three new studies began in the late 1990s and followed children through age 7. Pesticide exposures stem from farm work in more than 300 low-income Mexican-American families in California, researchers from the University of California, Berkeley and their colleagues report. In two comparably sized New York City populations, exposures likely trace to bug spraying of homes or eating treated produce.”

Among the California families, the average IQ for the 20 percent of children with the highest prenatal organophosphate exposure was 7 points lower compared with the least-exposed group.

“There was an amazing degree of consistency in the findings across all three studies,” notes Bruce Lanphear of Simon Fraser University in Vancouver. And that’s concerning, he says, because a drop of seven IQ points “is a big deal. In fact, half of seven IQ points would be a big deal, especially when you see this across a population.”[5]

There is no dispute about the fact that cotton crops are grown using many millions of pounds of chemical pesticides and synthetic fertilizers.  And research shows that extensive and intensive use of synthetic fertilizers, soil additives, defoliants and other substances wreak terrible havoc on soil, water, air and many, many living things – such as in the study cited above.

So what is the point that’s being missed?  Because conventional agriculture – despite advances in IPM – uses so many chemicals which are bad for us, shouldn’t the crops be grown organically?  That cuts to the chase –  in organically raised crops, there would be no toxic residues in the fibers, nor would the chemicals be wreaking havoc on our soils, water and air.  So the question of whether there are pesticide residues in the fibers becomes moot.  And though the United States and other countries might have banned the use of some chemicals, such as DDT, they’re still in use in parts of the world.

We’ve often touted the benefits of organic agriculture, and seems to be yet another.  We think organic farming is so important that we’ll spend some time on the subject in our next few posts – because there are some who say that organic farming is just not the answer.  Are we between a rock and a hard place?

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[1] Five of the top nine pesticides used on cotton in the U.S. (cyanide, dicofol, naled, propargite, and trifluralin) are known cancer-causing chemicals. All nine are classified by the U.S. EPA as Category I and II (dangerous chemicals).

[2] The purpose of the Bremen Cotton Exchange is “to maintain and promote the interests of all those connected with the cotton trade”.

[3] Zhang, X., Liao, Q and Zhang, Y, “Simultaneous determination of nine organochlorine pesticide residues in textile by high performance liquid chromatography, SEPU, 2007, 25(3), 380-383.

[4] http://www.scribd.com/doc/55465538/Insecticide-Residues-on-Cotton-Soils ALSO: Journal of Agricultural, Food and Environmental Sciences, Vol 1, Issue 1, 2007; “Pesticide Residues in Soil and Water from Four Cotton Growing Areas of Mali, West Africa   ALSO: Luchini, LC et al., “Monitoring of pesticide residues in a cotton crop soil”, Journal of Environmental Science and Health, January 2000, 35(1): 51-9  SEE ALSO: http://www.bashanfoundation.org/ivan/ivanmapping.pdf

[5] http://www.sciencenews.org/view/generic/id/73206/title/Pesticides_tied_to_lower_IQ_in_children

Biopolymers and polylactic acid (PLA) – or rather, Ingeo

Synthetic polymers have experienced almost exponential growth since 1950, and today about 5% of world oil production is used for that purpose.  In fact, we will need 25% or more of the current oil production for making polymers by the end of this century.

Some synthetic polymers are used to make fibers, and they have been around for a while:  rayon was discovered in 1924 and nylon in 1939.  But synthetic use really began to take off only since about 1953,  when polyester was discovered.  Qualities like durability and water resistance make synthetics highly desirable in many applications.  Today synthetics account for about half of all fiber usage.

This, despite the fact that synthetics are made from fossil fuel, and the contaminants from the manufacturing leach into our waterways and pollute the atmosphere, and the fact that they are not biodegradable and therefore don’t break down in landfills.  So recently there has been a spotlight on bio-plastics.

Bio plastics, or biopolymers -  in other words, synthetic plastics produced from biological sources -  are derived from cellulose. Cellulose is abundant – it’s said to make up half of all the organic carbon on the planet.   The most often-used biopolymers  include:

• natural rubber (in use since the mid-1700s),
• cellulosics (invented in the late-1800s),
• and nylon 11 (polyamide – or PA 11) and 6–10 (polyamide 6/10) (mid-1900s).

A recent addition to the list is polylactic acid (PLA).  PLA is made from corn starch (in the United States), tapioca products (roots, chips or starch, mostly in Asia) or sugar cane (the rest of the world).[1]  You’ve probably heard about polylactic acid (PLA),  because Cargill, one of the largest agricultural firms on Earth, has invested heavily in it.  Cargill’s wholly owned subsidiary, NatureWorks, is the primary producer of PLA in the United States.  The brand name for NatureWorks PLA is Ingeo, which is made into a whole array of products, including fabrics.

The producers of PLA have touted the eco friendliness of PLA based on:

1. the fact that it is made from annually renewable resources ,
2.  that it will biodegrade in the environment all the way to carbon dioxide and water  -  at least in principle, and
3. they also cite PLA’s lower carbon footprint.

Let’s take a look at these three claims.

Plant based biopolymers do come from renewable resources, but the feedstock used presents some interesting problems.  In the United States, corn is used to make the PLA. In the US, corn-based biopolymer producers have to compete with ethanol producers of government mandated gasoline blends, raising the cost and limiting availability for both. This problem will become worse in the future as the law requires a doubling of the percentage of ethanol used in motor fuel. Nearly a third of the US corn crop previously used for food was used to replace 5% of gasoline consumption in 2008.[2]

In a world where many people are starving, many say that it seems almost criminal to grow food crops, such as corn, to turn it into cloth. Agricultural lands are often cleared to make way for the growing of crops for the production of polymers. This leads to a continuous shrinking of the food producing lands of the world.  Lester Brown, president of the Earth Policy Institute, says, “already we’re converting 12% of the US grain harvest to ethanol (anticipated to rise to 23% by 2014). How much corn do we want to convert to nonfood uses?”[3]

In addition, most of the corn used by NatureWorks to make PLA is genetically modified, which raises serious ethical issues.

Other critics point to the steep environmental toll of industrially grown corn. The cultivation of corn uses more nitrogen fertilizer, more herbicides and more insecticides than any other U.S. crop; those practices contribute to soil erosion and water pollution when nitrogen runs off fields into streams and rivers.

PLA is said to decompose into carbon dioxide and water in a “controlled composting environment” in 90 days or less.  What’s that?  Not exactly your backyard compost heap!  It’s an industrial facility where microbes work at 140 degrees or more for 10 consecutive days.  In reality very few consumers have access to the sort of composting facilities needed to degrade PLA.  NatureWorks has identified 113 nationwide – some handle industrial food-processing waste or yard trimmings, others are college or prison operations .  Moreover, PLA in quantity can interfere with municipal compost operations because it breaks down into lactic acid, which makes the compost wetter and more acidic.

It looks like most PLA will end up in landfills, where there is no evidence it will break down any faster than PET.  Glenn Johnston, manager of global regulatory affairs for NatureWorks, says that a PLA container dumped into a landfill will last as long as a PET bottle.[4]

In fact, manufacturers have changed their stance: PLA is now defined as “compostable” instead of biodegradable, meaning more heat and moisture is needed to degrade PLA than is found in your typical backyard compost bin.

So far, biopolymer producers have had problems demonstrating that their materials have smaller carbon footprints than fossil fuel-derived polymers.   The energy inefficiencies of planting, growing, and transporting biological feedstocks mean more total energy is likely consumed to produce a unit of biopolymer than to make a unit of an oil or gas-based polymer.

However, Ramani Narayan of Michigan State University  found that “the results for the use of fossil energy resources and GHG emissions are more favorable for most bio based polymers than for oil based. As an exception, landfilling of biodegradable polymers can result in methane emissions (unless landfill gas is captured) which may make the system unattractive in terms of reducing greenhouse gas emissions.”[5]

Dr. Narayan recommended that, relative to their conventional counterparts, green polymers  should:

• save at least 20 MJ (non-renewable) energy per kg of polymer,
• avoid at least 1 kg CO2 per kg polymer and
• reduce most other environmental impacts by at least 20%.

From this point of view, he says,  green plastics  can be defined in a broad and target-oriented manner.

But  carbon footprints may be an irrelevant measurement, because it has been established that plants grow more quickly and are more drought and heat resistant in a CO2 enriched atmosphere. Many studies have shown that worldwide food production has risen, possibly by as much as 40%, due to the increase in atmospheric CO2 levels. Therefore, it is both ironic  and a significant potential problem for biopolymer production if the increased CO2 emissions from human activity were rolled back, causing worldwide plant growth to decline.  This in turn would greatly increase the  competition for biological sources of food and fuel –  with biopolymers coming in last place.[6]

A further problem with biopolymers (except for future PE/PP made from sugar cane) is that  they require additional sorting at commercial recycling centers to avoid contaminating other material streams, and, although segregated collection helps, it is complex and increases costs.

In the final analysis, newer biopolymers don’t yet perform as well as oil based polymers, especially in terms of lower heat and moisture resistance, so the user might feel green but gets results that are less sustainable and more limited in use.  PLA remains a boutique polymer, and some see the best value proposition for biopolymers to be where their use is based on their unique properties, such as in medical and dental implants, sutures, timed released chemotherapy, etc. , because  PLA will slowly come apart in the body over time, so it can serve as a kind of scaffold for bone or tissue regrowth or for metered drug release.  But this is a small and specialized market.

But still, the potential and need for plastic alternatives has become acute:  The SPI Bioplastic Council anticipates that the biopolymer market will exceed $1 billion by 2012 – today it is half that.   Bioplastic remains “a sector that is not yet mature but will be growing fast in the coming years,” says Frederic Scheer , CEO of Cereplast and the so-called ‘Godfather of Bioplastics.’  It has not matured because of high production costs and the restricted capacity of biomass-based polymers.

But  according to The ETC Group, there are already concerted efforts, using biotechnology,  to shift global industrial production from a dependence on fossil fuels to biomass – not only for plastics but also for power, chemicals, and more.  It sounds good – until you read their report, which I’ll cover next week.

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[1] Wikipedia http://en.wikipedia.org/wiki/Polylactic_acid

[2] Jones, Roger, “Economics, Sustainability, and the Public Perception of Biopolymers”, Society of Plastics Engineers, http://www.4spepro.org/pdf/000060/000060.pdf

[3] Royte, Elizabeth, “Corn Plastic to the Rescue”, Smithsonian,  August 2006

[4] Ibid.

[5] Narayan, Ramani, “Review and Analysis of Bio-based Product LCA’s”, Department of Chemical Engineering & Materials Science, Michigan State University, East Lansing, MI 48824

[6] D. B. Lobell and C. B. Field, Global scale climate-crop yield relationships and the impacts

of recent warming, Env. Res. Letters 2, pp. 1–7, 2007  AND

L. H. Ziska and J. A. Bunce, Predicting the impact of changing CO2 on crop yields:

some thoughts on food, New Phytologist 175, pp. 607–618, 2007.

When is recycled polyester NOT recycled polyester?

Fabric might be the only product I can think of which is known by its component parts, like cotton, silk, wool.  These words usually refer to the fabric rather than the fiber used to make the fabric.  We’ve all done it: talked about silk draperies, cotton sheets.  There seems to be a disassociation between the fibers used and the final product, and people don’t think about the process of turning cotton bolls or silkworm cocoons or flax plants into luxurious fabrics.

There is a very long, involved and complex process needed to turn raw fibers into finished fabrics.  Universities award degrees in textile engineering,  color chemistry or any of a number of textile related fields.  One can get a PhD in fiber and polymer science,  or study the design, synthesis and analysis of organic dyes and pigments.  Then there is the American Association of Textile Chemists and Colorists (AATCC) which has thousands of members in 60 different countries.  My point is that we need to start focusing on the process of turning raw textile fiber into a finished fabric – because therein lies all the difference!

And that brings me to recycled polyester, which has achieved pride of place as a green textile option in interiors.  We have already posted blogs about plastics (especially recycled plastics) last year (on 4.28.10, 5.05.10 and 5.12.10) so you know where we stand on the use of plastics in fabrics.  But the reality is that polyester bottles exist,  and recycling some of them  into fiber seems to be a better use for the bottles than landfilling them.

But today the supply chains for recycled polyester are not transparent, and if we are told that the resin chips we’re using to spin fibers are made from bottles – or from any kind of  polyester  -  we have no way to verify that.  Once the polymers are at the melt stage, it’s impossible to tell where they came from, because the molecules are the same.  So the yarn/fabric  could be virgin polyester or  it could be recycled.   Many so called “recycled” polyester yarns may not really be from recycled sources at all because – you guessed it! – the process of recycling is much more expensive than using virgin polyester.   And unfortunately not all companies are willing to pay the price to offer a real green product, but they sure do want to take advantage of the perception of green.   So when you see a label that says a fabric is made from 50% polyester and 50% recycled polyester – well, there is absolutely no way to tell if that’s true.

Some companies are trying to differentiate their brands by confirming that what they say is recycled REALLY is from recycled sources.  Unifi, which supplies lots of recycled resins and yarns, has an agreement with Scientific Certification Systems to certify that their Repreve yarns are made from 100% recycled content.  Then Unifi’s  “fiberprint” technology audits orders across the supply chain to verify that if Repreve is in a product , that it’s present in the right amounts.  But with this proprietary information there are still many questions Unifi doesn’t answer – the process is not transparent.  And it applies only to Unifi’s branded yarns.

Along with the fact that whether what you’re buying is really made from recycled yarns – or not – most people don’t pay any attention to the processing of the fibers.  Let’s just assume, for argument’s sake, that the fabric (which is identified as being made of 100% recycled polyester) is really made from recycled polyester.  But unless they tell you specifically otherwise, it is processed conventionally.  That means that the chemicals used during processing – the optical brighteners, texturizers, dyes, softeners, detergents, bleaches and all others – probably contain some of the chemicals which have been found to be harmful to living things.  The processing uses the same amount of water (about 500 gallons to produce 25 yards of upholstery weight fabric) – so the wastewater is probably expelled without treatment, adding to our pollution burden.  And there is no guarantee that the workers who produce the fabric are being paid a fair wage – or even that they are working in safe conditions.

One solution, suggested by Ecotextile News, is to create a tracking system that follows the raw material through to the final product.  They assumed that this would be very labor intensive and would require a lot of monitoring (all of which adds to the cost of production – and don’t forget, recycled polyester now is fashion’s darling because it’s so cheap!).

But now, Ecotextile News‘ suggestion has become a reality.   There is a new, third party certification which is addressing these issues.  The Global Recycle Standard (GRS), issued by Control Union, is intended to establish independently verified claims as to the amount of recycled content in a yarn. The GRS provides a track and trace certification system that ensures that the claims you make about a product can be officially backed up. It consists of a three-tiered system with the Gold standard requiring products to contain between 95 percent to 100 percent recycled material; the Silver standard requires products to be made of between 70 percent to 95 percent recycled product; and the Bronze standard requires products to have a minimum of 30 percent recycled content.

And – we think this is even more important -  in addition to the certification of the recycled content, the GRS looks at the critical issues of processing and workers rights.  This new standard holds the weaver to similar standards as found in the Global Organic Textile Standard:

• companies must keep full records of the use of chemicals, energy, water consumption and waste water treatment including the disposal of sludge;
• all prohibitied chemicals listed in GOTS are also prohibited in the GRS;
• all wastewater must be treated for pH, temperature, COD and BOD before disposal;
• there is an extensive section related to worker’s health and safety.