Synthetic fibers and our oceans

18 02 2012

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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Issues with using recycled polyester

31 03 2010

It looks like the plastic bottle is here to stay, despite publicity about bisphenol A  and other chemicals that may leach into liquids inside the bottle.   Plastic bottles (which had been used for some kind of consumer product) are the feedstock for what is known as “post consumer recycled polyester”.  Recycled polyester, also called rPET, is now accepted as a “sustainable” product in the textile market.   In textiles, most of what passes for “sustainable” claims by manufacturers have some sort of recycled polyester in the mix, because it’s a message that can be easily understood by consumers – and polyester is much cheaper than natural fibers.

The recycled market today has lots of unused capacity – as well as great potential for growth, because the recycling rates in many high consumption areas (like Europe and the USA) are low but growing.   In Europe, collection rates for bottles rose to 46% of all PET bottles on the market, while in the US the rate is 27%.   Factories are investing in technology and increasing their capacity – so the demand is huge.  According to Ecotextile News, beggars in China will literally stand watching people drink so that they can ask for the empty bottle.

As the size of the recycled polyester market grows, we think the integrity of the sustainability claims for polyesters will become increasingly important.  There has not been the same level of traceability for polyesters as there is for organically labelled products.  According to Ecotextile News, this is due (at least in part) to lack of import legislation for recycled goods.

When you buy a fabric that claims it’s made of 100% post consumer polyester – how do you know that the fibers are 100% post consumer?  Is there a certification which assures us that the fibers really are what the manufacturer says they are?  And it’s widely touted that recycling polyester uses just 30 – 50% the energy needed to make virgin polyester – but is that true in every case?  And what about water use – it’s widely thought that water use needed to recycle polyester is low, but who’s looking to see that this is true?

Recycled post consumer polyester is made from bottles – which have been collected, sorted by hand, and then melted down and formed into chips (sometimes called flakes).  These chips or flakes are then sent to the yarn spinning mills, where they’re melted down and (if not used at 100% rates) mixed with virgin polyester.   A fabric made of “recycled polyester” has a designated percentage of those chips in the polymer.  The technology has gotten so sophisticated that it’s now difficult to verify if something is really recycled.

First, let’s look at how the recycled polyester is used in textiles, beyond the issue of whether the recycled PET yarns actually ARE spun from recycled feedstock,  because there are several issues with using recycled PET which are unique to the textile industry:

  • The base color of the recyled chips varies from white to creamy yellow.  This makes it difficult to get consistent dyelots, especially for pale shades.
  • In order to get a consistently white base, some dyers use chlorine-based bleaches.
  • Dye uptake can be inconsistent, so the dyer would need to re-dye the batch.  There are high levels of redyeing, leading to increased energy use.
  • PVC is often used in PET labels and wrappers and adhesives.  If the wrappers and labels from the bottles used in the post consumer chips had not been properly removed and washed, PVC may be introduced into the polymer.
  • Some fabrics are forgiving in terms of appearance and lend themselves to variability in yarns,  such as fleece and carpets; fine gauge plain fabrics are much more difficult to achieve.

And of course, the chemicals used to dye the polymers as well as the processing methods used during weaving of the fabric may – or may not – be optimized to be environmentally benign.  Water used during weaving of the fabric may – or may not –  be treated.  And the workers may – or may not – be paid a fair wage.

One solution, suggested by Ecotextile News, is to create a tracking system that follows the raw material through to the final product.  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!).  There are also private standards which have begun to pop up, in an effort to differentiate their brands.  One fiber supplier which has gone the private standard route is Unifi.   Repreve is the name of Unifi’s recycled polyester – the company produces recycled polyester yarns, and (at least for the filament yarns) they have Scientific Certification Systems certify that Repreve yarns are made with 100% recycled content.  Unifi’s  “fiberprint” technology audits orders across the supply chain  to verify that if Repreve is in a product it’s present in the right amounts.  But there are still  many unanswered questions (because they’re  considered “proprietary information” by Unifi)  so the process is not transparent.

But now there is a new, third party certification which is addressing these issues.  The Global Recycle Standard, issued by Control Union, is intended to establish independently verified claims as to the amount of recycled content in a yarn.  In addition to the certification of the recycled content, 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 wastewater must be treated for pH, temperature, COD and BOD before disposal;
  • there is an extensive section related to worker’s health and safety.

In the end, polyester – whether recycled or virgin – is plastic.

I came across the work of a photographer living in Seattle, Chris Jordan, who published photographs of albatross chicks which he made in September, 2009, on Midway Atoll, a tiny stretch of sand and coral near the middle of the North Pacific.   As he says, “The nesting babies are fed bellies-full of plastic by their parents, who soar out over the vast polluted ocean collecting what looks to them like food to bring back to their young. On this diet of human trash, every year tens of thousands of albatross chicks die on Midway from starvation, toxicity, and choking.

To document this phenomenon as faithfully as possible, not a single piece of plastic in any of these photographs was moved, placed, manipulated, arranged, or altered in any way. These images depict the actual stomach contents of baby birds in one of the world’s most remote marine sanctuaries, more than 2000 miles from the nearest continent.”  See more at Chris Jordan’s website here.

To make thing worse, these tiny pieces of plastic are extremely powerful chemical accumulators for organic persistent pollutants present in ambient sea water such as DDE’s and PCB’s. The whole food chain,  from invertebrates to fish, turtles and mammals … are eating plastic and /or other animals who have plastic in them.

If you’re shocked by this picture, remember that this was brought to our attention years ago by National Geographic Magazine and in reports by scientists from many organizations.  One of the things they warned us of is the Great Pacific Garbage Patch, which has doubled in size while we have done nothing.  I am shocked that we have done nothing while the cascading effects of our disposable society continue to accumulate.