Wool

9 06 2010

When we talk about wool, we almost always mean the fiber from sheep, although the term “wool” can be applied to the hair of other mammals including cashmere and mohair from goats, vicuna, alpaca and camel from animals in the camel family and angora from rabbits.

As with many discoveries of early man, anthropologists believe the use of wool came out of the challenge to survive – Neolithic man used pelts from animals to keep warm.

Sheep (Ovis aries) were first domesticated 10 000 years ago.  The British sought to protect their own wool industry during the eighteenth century, and passed laws requiring native English wool be used – for example, judges, professors, and students were required to  wear robes made of English wool. Another law required that the dead be buried in native wool. When the American colonies began to compete with the motherland, the English passed a series of laws in an attempt to protect their “golden fleece.” One law even threatened the amputation of the hand of any colonist caught trying to improve the blood line of American sheep.

Today, wool is a global industry, with Australia, Argentina, the United States, and New Zealand serving as the major suppliers of raw wool – but wool is produced worldwide in about 100 countries on half a million farms.   Wool producers range from small farmers to large scale grazing operations.  While the United States is the largest consumer of wool fabric, Australia is the leading supplier. Australian wool accounts for approximately one-fourth of the world’s production.

The annual global output is now estimated at 2.2 billion pounds, yet wool represents less than 5 percent of the world consumption of fibers. Wool is an expensive fiber to produce and process.  Though cotton is the number one plant used for fabrics and the number one natural fiber overall, the number one source for animal fiber is still wool.

Two terms one often sees are Merino and worsted.  The main difference between them is that Merino pertains to the type of fiber while worsted pertains to the process the fibers go through:

Merino is a term used in the textile industry which has varied meanings:  originally it meant wool made from a specific breed of sheep:  the Merino.  Merino sheep are regarded as having some of the finest and softest wool of any sheep: it is finely crimped and soft, fibers are commonly 65 – 100 mm (2.5 – 4 inches) long and generally less than 24 microns in diameter.

But now the term has broader use and may pertain to an article which just contains some percentage of wool from Merino sheep – or even just a fine wool and cotton yarn!  The Australian Wool Testing Authority Ltd is trying to institute a definition for Merino wool, citing fiber diameter and comfort factors.

The essential feature of a worsted yarn is its long, straight fibers which lie parallel to each other, the result of having been both carded AND combed.

So yes, you can have Merino worsted wools!

THE FIBER:

In scientific terms, wool is considered to be a protein called keratin. Its length usually ranges from 1.5 to 15 inches (3.8 to 38 centimeters) depending on the breed of sheep. Fiber diameter ranges from 16 microns in superfine merino wool (similar to cashmere) to more than 40 microns in coarse hairy wools.  Wool has several qualities that distinguish it from hair or fur: it is crimped (meaning it has waves),  it has a different texture or handle, it is  elastic, and it grows in staples (clusters).

Each wool fiber is made up of three essential components: the cuticle, the cortex, and the medulla.

  • The cuticle is the outer layer. It is a protective layer of scales arranged like shingles or fish scales.   They are sometimes described as little “barbs” because it’s the points of the scales that give wool the reputation for being prickly.
    • When two fibers come in contact with each other, these scales tend to cling and stick to each other. It’s this physical clinging and sticking that allows wool fibers to be spun into thread so easily.  And it’s also what causes the fiber to interlock – or felt.   See below for more information on this.

    Scales on a wool fiber under electron microscope

  • The cortex is the inner structure made up of millions of cigar-shaped cortical cells. The arrangement of these cells is responsible for the natural crimp unique to wool fiber.  The amount of crimp corresponds to the fineness of the wool fibers.  A fine wool like Merino may have up to 100 crimps per inch, while the coarser wools may have as few as 1 to 2. Hair, by contrast, has little if any scales and no crimp, and little ability to bind into yarn.  Its wool’s scaling and crimp that make it easier to spin into yarn, because the individual fibers attach to each other, so they stay together.
  • Rarely found in fine wools, the medulla comprises a series of cells (similar to honeycombs) that provide air spaces, giving wool its thermal insulation value.

The Manufacturing Process

The major steps necessary to process wool from the sheep into yarns are:  shearing, cleaning and scouring, grading and sorting, carding.

SHEARING:

Sheep are usually sheared once a year—usually in the springtime. The fleece recovered from a sheep can weigh between 6 and 18 pounds (2.7 and 8.1 kilograms); as much as possible, the fleece is kept in one piece. While most sheep are still sheared by hand, new technologies have been developed that use computers and sensitive, robot-controlled arms to do the clipping.

GRADING AND SORTING:

Grading is the breaking up of the fleece based on overall quality. Wool fibers are judged not only on the basis of their strength but also by their fineness (diameter), length, crimp (waviness) and color.  In wool grading, high quality does not always mean high durability.

In sorting, the wool is broken up into sections of different quality fibers, from different parts of the body. The best quality of wool comes from the shoulders and sides of the sheep and is used for clothing; the lesser quality comes from the lower legs and is used to make rugs.

CLEANING AND SCOURING:

Scouring in the true sense of the word in the textile industry means simply removing any foreign material from the fabric; the term scour grew up around the washing of cottons and linens.

Wool taken directly from the sheep is called “raw” or “greasy”  wool.  It contains a substantial amount of natural contaminants, such as  sand, dirt, grease, and dried sweat (called suint) as well as pesticide residues from the treatment of sheep to prevent disease; the weight of contaminants accounts for about 30 to 70%  of the total weight of the fleece.

To clean the wool, the fiber is washed in a series of alkaline baths containing water, soap, and soda ash or a similar alkali. The scouring effluent contains these impurities, which has high levels of COD (chemical oxygen demand) and BOD (biochemical oxygen demand), suspended solids, organic matter and sheep dip chemicals.  These levels represent a significant pollution load:   the organic effluent from a typical wool-scouring plant is approximately equal to the sewage from a town of 50,000 people.[1]

The effluent is separated into three categories:

  1. grease – when refined, this is known as lanolin, which is saved and sold for a variety of consumer products.
  2. liquor (water) – discharged to sewage works or open waters
  3. sludge – this needs to be disposed of too:   The sludge contains high levels of organic materials such as the potentially toxic sheep dip pesticides (such as organochlorines, organophosphates and synthetic prethroids).   In the EU, landfills will now only accept non-recoverable and inert waste.  Since the global production of wool sludge is over 930,000 tons, research is being done on the feasibility of disposing of scouring waste by composting, incineration and other methods.

The processing stages to this point cause the natural fiber alignment of the scales (or “barbs” as mentioned above) to be completely disrupted; the scales no longer line up “tip to base” as they would in the fleece. Those scales make raw wool itchy and also cause the fiber to shrink when wet.

In order to prevent this shrinkage (also called felting), and to make the wool more comfortable when worn next to the skin, many producers use chlorine to “burn” off the scales…this doesn’t entirely remove them, but it does lessen their profile, and then the fibers are coated with a synthetic polymer resin, which essentially glues down the scales. This allows the wool to be machine washed without felting, and gets rid of the shrinkage of the fabric associated with felting.  This is the chemistry behind Superwash wool.  The tradeoff, of course, is that this chlorination process is highly toxic.

See our blog post on Organic Wool to read about the environmental effects of wool scouring and chlorination.  It’s not pretty.

CARDING:

Next, the fibers are passed through a series of metal teeth.  The teeth untangle the fibers and arrange them into a flat sheet called a web. The web is then formed into narrow ropes known as silvers.   Carding  is one of the processes that untangles the wool fibers and lays them straight; it also removes residual dirt and other matter left in the fibers.  Combing is the next process, which removes shorter length fibers and helps to further straighten the fibers and lay them parallel.  Combing also helps to clean more debris from the fibers.

  • Carding only produces woolenyarn.   Woolen yarns:
    • Have a short staple (1-4 inch long fibers).
    • Are carded ONLY
    • Have a slack twist
    • Are weaker, softer and bulkier than worsted
  • Carding and Combing produces worsted yarn.Worsted yarns:
    • Have a long staple (4 inch and longer)
    • Have a tight twist in spinning
    • Are stronger, finer, smoother and harder than woolen yarns.

CHARACTERISTICS of WOOL:

Wool is highly regarded as one of the most lavish natural fibers in the world.  Lightweight, versatile, resistant to dirt and considered somewhat water repellant, non wrinkling, and durable, wool:

  • Can absorb almost 30% of its own weight in water – and it can also release it.  This makes it breathable and extremely comfortable next to the skin.  It can absorb sweat and release it as vapor, keeping you cool and dry.  It prevents the clammy, cold feeling you may experience when wearing some types of synthetic clothing and sweating.
  • Is resistant to static electricity,  because the moisture retained within the fabric conducts electricity. This is why wool garments are much less likely to spark or cling to the body. The use of wool car seat covers or carpets reduces the risk of a shock when a person touches a grounded object.
  • fabrics have a greater bulk than other textiles because of the crimp, and retain air, which is a great insulation.  It keeps you warm when you’re cold, but insulation also works both ways – Bedouins and Tuaregs use wool clothes to keep the heat out.  And it does not cling to the skin, allowing for air circulation next to the skin.
  • fibers can be bent 20,000 times without breaking (compared to cotton, which breaks after 3,000 bends or rayon, which can be bent only 75 times without breaking), and have the power to elongate (it can be stretched 25 – 30% before breaking), stretch and recover. This natural elasticity and memory  returns to its natural shape
  • doesn’t readily catch fire – its ignition point is higher than cotton and some synthetics.  Even if it does burn, it burns slowly (not melting or dripping as in synthetics) and self-extinguishes when the source of the flame is removed.  It contributes less to toxic gases and smoke than synthetics, and is therefore often specified for high safety environments such as trains and aircraft.
  • has a naturally high UV protection, which is much higher than most synthetics and cotton.
  • is considered by the medical profession to be hypoallergenic.
  • is hydrophilic—it has a strong affinity for water—and therefore is easily dyed.

[1] Christoe, Jock; The treatment of wool scouring effluents in Australia, China and India”,  project # AS1/1997/069; http://aciar.gov.au/system/files/node/9074/AS%2003-04%20AS1-1997-069.pdf





Why buy natural fibers instead of synthetics?

26 05 2010


Since the 1960s, the use of synthetic fibers has increased dramatically,  causing the natural fiber industry to lose much of its market share. In December 2006, the United Nations General Assembly declared 2009 the International Year of Natural Fibres (IYNF); a year-long initiative focused on raising global awareness about natural fibers with specific focus on increasing market demand to help ensure the long-term sustainability for farmers who rely heavily on their production.

International Forum for Cotton Promotion

Since I have recently been ranting about the plastics industry I thought it was time to turn to natural fibers, which have a history of being considered the highest quality fibers, valued for their comfort, soft hand and versatility.  They also carry a certain cachet:  cashmere, silk taffeta and 100% pure Sea Island cotton convey different images than does 100% rayon,  pure polyester or even Ultrasuede, don’t they?  And natural fibers, being a bit of an artisan product, are highly prized especially in light of campaigns by various trade associations to brand its fiber:    “the fabric of our lives” from Cotton, Inc. and merino wool with the pure wool label are two examples. 

Preferences for natural fibers seem to be correlated with income; in one study, people with higher incomes preferred natural fibers by a greater percentage than did those in lower income brackets.   Cotton Incorporated funded a study that demonstrated that  66% of all women with household incomes over $75,000 prefer natural fibers to synthetic.

What are the reasons, according to the United Nations, that make natural fibers so important?  As  the UN website, Discover Natural Fibers says:

  1. Natural fibers are a healthy choice.
    1. Natural fiber textiles absorb perspiration and release it into the air, a process called “wicking” that creates natural ventilation. Because of their more compact molecular structure, synthetic fibers cannot capture air and “breathe” in the same way. That is why a cotton T-shirt is so comfortable to wear on a hot summer’s day, and why polyester and acrylic garments feel hot and clammy under the same conditions. (It also explains why sweat-suits used for weight reduction are made from 100% synthetic material.) The bends, or crimp, in wool fibers trap pockets of air which act as insulators against both cold and heat – Bedouins wear thin wool to keep them cool. Since wool can absorb liquids up to 35% of its own weight, woollen blankets efficiently absorb and disperse the cup of water lost through perspiration during sleep, leaving sheets dry and guaranteeing a much sounder slumber than synthetic blankets.
    2. The “breathability” of natural fiber textiles makes their wearers less prone to skin rashes, itching and allergies often caused by synthetics. Garments, sheets and pillowcases of organic cotton or silk are the best choice for children with sensitive skins or allergies, while hemp fabric has both a high rate of moisture dispersion and natural anti-bacterial properties.   Studies by Poland’s Institute of Natural Fibers have shown that 100% knitted linen is the most hygienic textile for bed sheets – in clinical tests, bedridden aged or ill patients did not develop bedsores. The institute is developing underwear knitted from flax which, it says, is significantly more hygienic than nylon and polyester. Chinese scientists also recommend hemp fiber for household textiles, saying it has a high capacity for absorption of toxic gases.
  2. Natural fibers are a responsible choice.
    1. Natural fibers production, processing and export are vital to the economies of many developing countries and the livelihoods of millions of small-scale farmers and low-wage workers. Today, many of those economies and livelihoods are under threat: the global financial crisis has reduced demand for natural fibers as processors, manufacturers and consumers suspend purchasing decisions or look to cheaper synthetic alternatives.
    2. Almost all natural fibers are produced by agriculture, and the major part is harvested in the developing world.
      1. For example, more than 60% of the world’s cotton is grown in China, India and Pakistan. In Asia, cotton is cultivated mainly by small farmers and its sale provides the primary source of income of some 100 million rural households.
      2. In India and Bangladesh, an estimated 4 million marginal farmers earn their living – and support 20 million dependents – from the cultivation of jute, used in sacks, carpets, rugs and curtains. Competition from synthetic fibers has eroded demand for jute over recent decades and, in the wake of recession, reduced orders from Europe and the Middle East could cut jute exports by 20% in 2009.
      3. Silk is another important industry in Asia. Raising silkworms generates income for some 700 000 farm households in India, while silk processing provide jobs for 20 000 weaving families in Thailand and about 1 million textile workers in China. Orders of Indian silk goods from Europe and the USA are reported to have declined by almost 50% in 2008-09.
      4. Each year, developing countries produce around 500 000 tonnes of coconut fiber – or coir – mainly for export to developed countries for use in rope, nets, brushes, doormats, mattresses and insulation panels. In Sri Lanka, the single largest supplier of brown coir fiber to the world market, coir goods account for 6% of agricultural exports, while 500 000 people are employed in small-scale coir factories in southern India.
      5. Across the globe in Tanzania, government and private industry have been working to revive once-booming demand for sisal fiber, extracted from the sisal agave and used in twine, paper, bricks and reinforced plastic panels in automobiles. Sisal cultivation and processing in Tanzania directly employs 120 000 people and the sisal industry benefits an estimated 2.1 million people. However, the global slowdown has cut demand for sisal, forced a 30% cut in prices, and led to mounting job losses.
  3. Natural fibers are a sustainable choice.
    1. Natural fibers will play a key role in the emerging “green” economy based on energy efficiency, the use of renewable feed stocks in bio-based polymer products, industrial processes that reduce carbon emissions and recyclable materials that minimize waste.  Natural fibers are a renewable resource, par excellence – they have been renewed by nature and human ingenuity for millennia. They are also carbon neutral: they absorb the same amount of carbon dioxide they produce. During processing, they generate mainly organic wastes and leave residues that can be used to generate electricity or make ecological housing material. And, at the end of their life cycle, they are 100% biodegradable.
    2. An FAO study estimated that production of one ton of jute fiber requires just 10% of the energy used for the production of one ton of synthetic fibers (since jute is cultivated mainly by small-scale farmers in traditional farming systems, the main energy input is human labor, not fossil fuels).
    3. Processing of some natural fibers can lead to high levels of water pollutants, but they consist mostly of biodegradable compounds, in contrast to the persistent chemicals, including heavy metals, released in the effluent from synthetic fiber processing. More recent studies have shown that producing one ton of polypropylene – widely used in packaging, containers and cordage – emits into the atmosphere more than 3 ton of carbon dioxide, the main greenhouse gas responsible for global warming. In contrast, jute absorbs as much as 2.4 tonnes of carbon per tonne of dry fiber.
    4. The environmental benefits of natural fiber products accrue well beyond the production phase. For example, fibers such as hemp, flax and sisal are being used increasingly as reinforcing in place of glass fibers in thermoplastic panels in automobiles. Since the fibers are lighter in weight, they reduce fuel consumption and with it carbon dioxide emissions and air pollution.
    5. But where natural fibers really excel is in the disposal stage of their life cycle. Since they absorb water, natural fibers decay through the action of fungi and bacteria. Natural fiber products can be composted to improve soil structure, or incinerated with no emission of pollutants and release of no more carbon than the fibers absorbed during their lifetimes. Synthetics present society with a range of disposal problems. In land fills they release heavy metals and other additives into soil and groundwater. Recycling requires costly separation, while incineration produces pollutants and, in the case of high-density polyethylene, 3 tonnes of carbon dioxide emissions for every tonne of material burnt. Left in the environment, synthetic fibers contribute, for example, to the estimated 640 000 tonnes of abandoned fishing nets and gear in the world’s oceans.
  4. Natural fibers are a high-tech choice.
    1. Natural fibers have intrinsic properties – mechanical strength, low weight and low cost – that have made them particularly attractive to the automobile industry.
      1. In Europe, car makers are using mats made from abaca, flax and hemp in press-molded      thermoplastic panels for door liners, parcel shelves, seat backs, engine shields and headrests.
        1. For consumers, natural fiber composites in automobiles provide better thermal and acoustic insulation than fiberglass, and reduce irritation of the skin and respiratory system. The low density of plant fibers also reduces vehicle weight, which cuts fuel consumption.
        2. For car manufacturers, the moulding process consumes less energy than that of fibreglass and produces less wear and tear on machinery, cutting production costs by up to 30%. The use of natural fibres by Europe’s car industry is projected to reach 100 000 tonnes by 2010. German companies lead the way. Daimler-Chrysler has developed a flax-reinforced polyester composite, and in 2005 produced an award-winning spare wheel well cover that incorporated abaca yarn from the Philippines. Vehicles in some BMW series contain up to 24 kg of flax and sisal.  Released in July 2008, the Lotus Eco Elise (pictured above) features body panels made with hemp, along with sisal carpets and seats upholstered with hemp fabric. Japan’s carmakers, too, are “going green”. In Indonesia, Toyota manufactures door trims made from kenaf and polypropylene, and Mazda is using a bioplastic made with kenaf for car interiors.
    1. Worldwide, the construction industry is moving to natural fibres for a range of products, including light structural walls, insulation materials, floor and wall coverings, and roofing. Among recent innovations are cement blocks reinforced with sisal fibre, now being manufactured in Tanzania and Brazil. In India, a growing shortage of timber for the construction industry has spurred development of composite board made from jute veneer and coir ply – studies show that coir’s high lignin content makes it both stronger and more resistant to rotting than teak. In Europe, hemp hurd and fibres are being used in cement and to make particle boards half the weight of wood-based boards. Geotextiles are another promising new outlet for natural fibre producers. Originally developed in the Netherlands for the construction of dykes, geotextile nets made from hard natural fibres strengthen earthworks and encourage the growth of plants and trees, which provide further reinforcement. Unlike plastic textiles used for the same purpose, natural fibre nets – particularly those made from coir – decay over time as the earthworks stabilize.
  1. Natural fibers are a fashionable choice.

    John Patrick Organic Fall/Winter 2010

    1. Natural fibers are at the heart of a fashion movement that goes by various names: sustainable, green, uncycled, ethical, eco-, even eco-environmental. It focuses fashion on concern for the environment, the well-being of fiber producers and consumers, and the conditions of workers in the textile industry. Young designers now offer “100% carbon neutral” collections that strive for sustainability at every stage of their garments’ life cycle – from production, processing and packaging to transportation, retailing and ultimate disposal. Preferred raw materials include age-old fibres such as flax and hemp, which can be grown without agrochemicals and produce garments that are durable, recyclable and biodegradable. Fashion collections also feature organic wool, produced by sheep that have not been exposed to pesticide dips, and “cruelty-free” wild silk, which is harvested – unlike most silk – after the moths have left their cocoons.
    2. The Global Organic Textile Standard (GOTS)   sets strict standards on chemicals permitted in processing, on waste water treatment, packaging material and technical quality parameters, on factory working conditions and on residue testing.
    3. Sustainable fashion intersects with the “fair trade” movement, which offers producers in developing countries higher prices for their natural fibres and promotes social and environmental standards in fibre processing. Fair trade fashion pioneers are working with organic cotton producers’ cooperatives in Mali, hand-weavers groups in Bangladesh and Nepal, and alpaca producers in Peru. A major UK chain store launched in 2007 a fair trade range of clothing that uses cotton “ethically sourced” from farmers in the Gujarat region of India. It has since sold almost 5 million garments and doubled sales in the first six months of 2008.
    4. Another dimension of sustainable fashion is concern for the working conditions of employees in textile and garment factories, which are often associated with long working hours, exposure to hazardous chemicals used in bleaching and dyeing, and the scourge of child labor. The recently approved (November 2008) Global Organic Textile Standard, widely accepted by manufacturers, retailers and brand dealers, includes a series of “minimum social criteria” for textile processing, including a prohibition on the use of child labor, workers’ freedom of association and right to collective bargaining, safe and hygienic working conditions, and “living wages”.

For the next few weeks I’ll talk about various fiber types, starting with my favorite, hemp.





Air pollution and your cashmere sweater

4 11 2009

We’ll be at Greenbuild next week, booth 910, with our good friends from LIVE Textiles.  Please stop by to see us if you’re there.

We are introducing a new organic wool upholstery fabric at Greenbuild  (we’re hoping it will be GOTS certified, though it is touch and go as to whether the certificate will be in place by then – there are so many hoops!).    So for the past six months or so we’ve been learning lots about wool – and wool is a complicated subject!  It’s a gorgeous fiber, but it has, as we say, issues.  Not unsolvable, but like everything you have to know your suppliers and what questions are important to ask.  We talked about wool and animal husbandry in two previous posts (“What does organic wool mean?” 8.11.09 and “Why does wool get such high embodied energy ratings?” 8.4.09);  some of the issues surrounding wool are enumerated in those posts.

I’m always a sucker for soft and luxurious, so naturally when talking about wool I began hinting I’d like a cashmere fabric – or wool/cashmere blend.  But we looked into cashmere, and what we found is startling and unexpected: a story of how your cashmere sweater pollutes the air you breathe.    There is an improbable connection, according to Evan Osnos of the Chicago Tribune, “between cheap sweaters, Asia’s prairies and America’s air, (which) captures how the most ordinary shifts in the global economy are triggering extraordinary change.”  Please read Mr. Osnos’ article, “China’s Great Grab”, from which most of the information in this blog is taken.   He won the Asia Society’s Osborn Elliott Prize for distinguished journalism for this series.

Cashmere has recently become ubiquitous –  cashmere sweaters, for example, once so very high priced that the very word “cashmere” became synonymous with luxury,  are suddenly “affordable”.  Coincidentally, Saks Fifth Avenue ran a full page ad in Sunday’s  New York Times touting their low priced cashmere goods – and telling you to “Shop Smart”.   We’ll help you to shop smart – please read this post!

What happened to bring down the price of cashmere?  Behind this new affordable price tag is something the consumer rarely sees or thinks about: the cascade of consequences around the world when the might of Chinese production and western consumption converge on a scarce natural resource.

Cashmere comes from the downy underhair of special goats, the majority of which live in the coldest regions of China and Mongolia.  In fact, the world’s best and most expensive cashmere comes from the Alashan Plateau, an area in China’s north straddling the Mongolian border,  boiling hot in summer and way below zero in winter.  This area is part of China’s mythic grasslands, where Genghis Khan and his horde rode the limitless horizon.  The fiber itself, known as “diamond fiber” in China,  sells for 6 times the cost of ordinary wool.

This rare and wonderful fiber is remarkably soft, silky and warm.  Side by side under a microscope a single cashmere strand makes a human hair look like a rope.  And it was also synonymous with high price.  European spinning mills have sourced the best cashmere yarns from this region for years.

The combination of demand and high prices led to China’s rapid increase in production to meet that demand,  and  conditions were in place to create an almost perfect storm – with money to be earned from “diamond fiber”, herders rapidly increased their goat populations and caused severe overgrazing.  In  Inner Mongolia, for example, the livestock population increased from 2 million in 1949 to 28.5 million in 2004.(1)

20080318-desertification Julie Chaol

The goats are eating the grasslands bare:  Goats consume over 10% of their body weight daily in roughage, eating not just the grass but also their roots and stripping bark from seedlings, preventing the regrowth of trees.  The land is so barren that herders buy cut grass and corn by the truckload to keep their animals alive.  Overgrazing is so severe that the health of the goats is at risk: their birthrate is sinking and even the cashmere has begun to suffer from these stressed goats, with shorter, coarser, less valuable fiber.

In addition to stripping the land of all vegetation, the feet of these goats have been compared to stiletto heels, vs. the big soft pads of camel’s feet, which have a far lesser impact on the ground.  These “stiletto heel” hooves  pierce the crust formed on the land, and the fine sand beneath it takes flight.  So the animals remove the vegetation, and the winds finish the job by blowing away the top soil, transforming the grasslands into desert.

In this perfect storm, the rapid increase in the number of goats has occurred at the same time the area is undergoing a severe drought due to climate change.  The goats require water, which also leads to overuse of that resource.  So many cashmere plants and other industries have opened in Alashan that authorities must ration water, forcing each factory to close for days at a time. (2)

And without grass and shrubs to hold the dunes in place, the deserts in Alashan are expanding by nearly 400 square miles each year. The World Bank warned of grave consequences for the environment and for farmers.

Already desertification is causing millions of rural Chinese to migrate from their villages –  a migration on the scale of the Dust Bowl in the United States is taking place in China today. A study by the Asian Development Bank found 4,000 villages at risk of being swallowed by drifting sand (3)

Exhib_001031

But the environmental degredation doesn’t stop in Alashan.  Eroding grasslands means that silt is deposited into the headwaters of rivers that flow all across Asia: to India, Pakistan, Bangladesh and Southeast Asia.  And the dust storms, which have been a fact of life in this area of the world since before Genghis Kahn, are becoming increasingly common:  in the 1950s, China suffered an average of five dust and sand storms per year; in the 1990s storms struck 23 times each year.  (4)  These storms do a lot of damage:  A storm in 2002 forced 1.8 million South Koreans to seek medical help and cost the country $7.8 billion in damage to industries such as airlines and semiconductors, said the state-run Korea Environment Institute. (5)

And added to the damage the storms cause in China, they also act as a high altitude conveyor belt for pollution.  Think of it like this:  the dust and sand generated in Alashan  is sent east by the winds, where China’s coal powered industry adds pollution.  Together the noxious brew reaches the U.S. within five days, where it can combine with local pollution to exceed the limits of healthy air, according to Rudolf Husar, an atmospheric chemist at Washington University in St. Louis.(6)

According to Eric Osnos’ article, “Of most concern are ultra tiny particles that lodge deep in the lungs, contributing to respiratory damage, heart disease and cancer. One storm that began in China and Mongolia in spring 1998 caused a spike in air pollution that prompted health officials in Washington, Idaho, Oregon and British Columbia to issue warnings to the public.”

The situation has become so bad that herders are moving off the land to try their hand at trades in the cities, and the government is putting many new programs into place to help stem the damage which has been done (including banning grazing on some lands).  The price of cashmere has begun to climb.  But with ads such as the one from Saks, promoting yet another cheap product, these problems will continue to persist.

(1)  Osnos, Evan;  “China’s Great Grab: Your cheap sweather’s real cost”, The Chicago Tribune, December 16, 2006.

(2) Ibid.

(3) http://factsanddetails.com/china.php?itemid=389&catid=10&subcatid=66#07)

(4) Osnos, op cit.

(5) Ibid.

(6) Ibid.





What does organic wool mean?

11 08 2009

Last week we talked about the importance of livestock management in the battle against climate change.  It came as a real revelation to this city girl that large grazing animals are a vital and necessary part of the solution to climate change.   Sheep can actually help to improve soils, which improves the soil’s ability to absorb water and maintain its original nutrient balance – and most importantly, by increasing the organic matter in the soil, it makes the soil a highly effective carbon bank.

many sheep

So the management of the livestock can be beneficial – but it’s a long way from a sheep in the pasture to a wool fabric.  So let’s look at the wool produced by these sheep and examine  what “organic wool” means.

In order for wool to be certified organic in the U.S., it must be produced in accordance with federal standards for organic livestock production, which are:

  • Feed and forage used for the sheep from the last third of gestation must be certified organic.
  • Synthetic hormones and genetic engineering of the sheep is prohibited.
  • Use of synthetic pesticides on pastureland is prohibited and the sheep cannot be treated with parasiticides, which can be toxic to both the sheep and the people exposed to them.
  • Good cultural and management practices of livestock must be used.

A key point to remember about the USDA and OTA organic wool designations:  the organic certification extends only to livestock – it doesn’t  cover the  further processing of the raw wool. Should that be a concern?

Wool as shorn from the sheep is known as greasy (or raw) wool. Before it is suitable for further processing it must be washed to remove dirt, water soluble contaminants (called suint), and woolgrease – and there are a lot of these contaminants.  On average, each ton of greasy wool contains:

  • 150 KG woolgrease (when refined this is known as lanolin)
  • 40 KG suint
  • 150 KG dirt
  • 20 KG vegetable matter
  • 640 KG wool fiber

This process of washing the wool is known as scouring.  Scouring uses lots of water and  energy :

  • water for washing:  The traditional method of wool scouring uses large amounts of water to wash the wool – the wool is passed through a series of 4 – 8 wash tanks (bowls), each followed by a squeeze to remove excess water.   Typical scouring plants can consume up to half a million litres of water per day.
  • pollution: The scouring water uses detergents and other chemicals in order to remove contaminants in the greasy wool,  which creates the problem of disposing of the waste water without contaminating the environment.  In unmodified plants, a single scouring line produces a pollution load equivalent to the pollution produced by 30,000 people.[1]
  • energy: to power the scouring line.

wool scour diagram

What about the chemicals used?

Detergents used in wool scouring include alkylphenol ethoxylates (APEOs) or fatty alcohol ethoxylates (more benign); sodium carbonate (soda ash), sodium chloride and sodium sulphate.  APEOs are among those chemicals known as endocrine disruptors – they interfere with the body’s endocrine system   They’re known to be very toxic for aquatic life – they cause feminization of male fish, for example.  (Click here to see what happened to alligators in Florida’s Lake Apopka as a result of endocrine disruptors traced to effluents from a textile mill. )  More importantly they break down in the environment into other substances which are much more potent than the parent compound.  They’re banned in Europe.

The surface of wool fibers are covered by small barbed scales. These are the reason that untreated wool itches when worn next to skin.  So the next step is to remove the scales, which also shrinkproofs the wool.  Shrinking/descaling is done using a chlorine pretreatment sometimes combined with  a thin polymer coating.  (Fleece is soaked in tertiary amyl or butyl hypochlorite in solution and heated to 104° for one hour.   The wool absorbs 1.5% of the chlorine. [2] )   These treatments make wool fibers smooth and allow them to slide against each other without interlocking. This also makes the wool feel comfortable and not itchy.

Unfortunately, this process results in wastewater with unacceptably high levels of adsorbable organohalogens (AOX) – toxins created when chlorine reacts with available carbon-based compounds. Dioxins, a group of AOX, are one of the most toxic known substances. They can be deadly to humans at levels below 1 part per trillion. Because the wastewater from the wool chlorination process contains chemicals of environmental concern, it is not accepted by water treatment facilities in the United States. Therefore all chlorinated wool is processed in other countries, then imported.[3] (For more about chlorine, go to the nonprofit research group Environmental Working Groups report about chlorine, http://www.ewg.org/reports/considerthesource.)  There are new chlorine free shrink/descaling processes coming on the market, but they’re still rare.

Finally, there is the weaving of the yarn into fabric – and all the environmental problems associated with conventional weaving and finishing.  In addition to the environmental concerns associated with conventional weaving, dyeing, and finishing (see some of our earlier blog posts), wool is often treated for moth and beetle protection, using pyrethroids, chlorinated sulphonamide derivatives, biphenyl ether or urea derivatives, which cause neutrotoxic effects in humans.

In the last 10 years, the textile industry,  along with animal ethics groups like People for the Ethical Treatment of Animals,  have lobbied against the wool industry, taking a stand against unethical treatment of sheep. In 2004, U.S. retailer Abercrombie and Fitch became the first to sign on to an animal rights campaign boycott of Australian wool that stood firmly against the typical practices of mulesing (where folds of skin around the sheep’s anus are cut off with shears during the wool shearing) and live export of sheep to halal butchers when their wool production becomes minimal.  Other companies such as H&M,  Marks & Spencer,  Nike, Gap,  Timberland, and Adidas (among others) have since joined, sourcing wool from South Africa or South America (where mulesing is not done).  The result of this outcry has led to the increased production of both organic and ethical wool, though it is still relatively minor when compared to the overall global wool production.

To complicate things a bit more, each country maintains their own standards for “organic wool” – Australia, for instance, has no equivalence or agreement with US organic standards.  The International Wool Textile Organization (IWTO) has adopted a new organic wool standard (closely aligned with GOTS) which they hope will be accepted by its members.  In addition, many companies use the term “eco wool”, which means the wool is sheared from free range roaming sheep that have not been subjected to toxic flea dipping, and the fleece was not treated with chemicals, dyes or bleaches – but this is wide open to interpretation and exploitation.  According to the IWTO, “Eco wool” must meet the standards set by the EU Eco-label.

Wool is a fabulous fiber – in addition to its many other attributes, it smolders rather than burns, and tends to be self-extinguishing.  (Read what The Commonwealth Scientific and Industrial Research Organisation (CISRO), Australia’s national science agency,  has to say about the flame resistance of wool by clicking here:   http://www.csiro.au/files/files/p9z9.pdf )  So if you can find organic wool  – making sure, of course, that the term “organic” covers:

  • management of the livestock according to organic or holistic management principles
  • processing of the raw wool,  using newer, more benign processes rather than harmful scouring and descaling chemicals; and wastewater  treatment from scouring and processing
  • weaving according to Global Organic Textile Standards (GOTS).  Read more about GOTS here.

…then go for it!  Nothing is quite like it in terms of comfort, resilience, versatility and durability.

But first you have to find it.  And that means you’ll have to ask lots of questions because there are lots of certifications to hide behind.


[1]The Cleanier Production Case Studies Directory EnviroNET Australia, Environment Protection Group, November 1998

[2] “Textiles: Shrink-proof wool”, Time, October 17, 1938

[3] “Fabric: Chlorine Free Wool”,  Patagonia website, http://www.patagonia.com/web/us/patagonia.go?slc=en_US&sct=US&assetid=8516