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cotton fieldImages: Cotton and Cotton Field by Scottchan: http://www.freedigitalphotos.net/images/view_photog.php?photogid=1701

cotton

cotton
Images: Cotton pickers with permission from Cotton Made in Africa www.cottonmadeinafrica.org. © Aid by Trade Foundation.

Cotton

Alternatives to conventional cotton production are primarily the use of organic cotton. For cotton to be considered organic, it must be farmed without the use of pesticides, synthetic chemical fertilizers, and genetically engineered seeds (GM seeds). Organic cotton must be third-party certified in order to meet rigorous production standards, which include manufacturing as well as agricultural methods. The UK-based Soil Association is one of over 100 such certification agencies worldwide, which are accredited and audited by various bodies such as the International Federation of Organic Agricultural Movement or the US Department of Agriculture.

Organic cotton is typically more expensive than conventional cotton due to lower crop yields and fibres are often shorter as well. It is non-polluting, non-toxic, biodegradable, and can be recycled. Organic cotton farming uses crop rotation to enrich the soil and employs natural predators to control unwanted pests, this in turn means that the land can also be used to grow food alongside the cotton crops and eliminates the risk of harmful substances potentially entering the food chain through water supplies. Organic cotton farmers also receive a premium price for their quality cotton, and do not have to buy expensive chemicals, enabling them to increase their income.

Organic agricultural crops rely on crop rotation and natural substance for their growth and success.  The cultivation of organic cotton also uses less water than conventional cotton as the richer soil retains more moisture, but irrigation is still often required. Irrigation is typically relied on for the water supply of most crops, but it can damage ecosystems and drain underground water supplies.  To combat diminishing water supplies, wastewater recycling programs are often developed and implemented for irrigation and manufacturing purposes of organic cotton.

There are many sets of organic standards for agricultural products that have been developed by many certification bodies or other organizations, which are all based on a limited number of “basic” or “minimum” standards. In Europe, basic organic standards are set in a European Union Council’s Regulation from 1991. This regulation, ratified by EU member states, also regulates the word “organic” for agricultural products. In the USA, the basic standards for organic food products are set by the US Department of Agriculture (USDA) as part of the National Organic Programme (NOP), as these standards also apply to the cotton plant, because cotton, apart from the fibre, also produces food products in the form of vegetable oil and animal feed from cotton seed.

Unfortunately the EU Organic standards and USDA’s NOP do not address any of the many processes required to transform the fibre into fabric and therefore a garment could be made with organic cotton, but still be processed in mills with poor environmental practices that pollute waste waters with heavy metals, and could ultimately contain a high level of toxic chemical residues, (Pan UK, 2007).

In many parts of the world, cotton is grown in large plantations, but in Africa it is almost exclusively grown by smallholder farmers, using crop rotation; in other words the cotton is grown alternately with other crops such as the basic food crops maize, soy or groundnuts, which reduces leaching of soils and the occurrence of pests. Cotton is often a complementary cash crop – it is grown for sale, alongside the foods grown in subsistence farming. The growing methods which farmers are taught by Cotton made in Africa (CmiA) for example, help the smallholder farmers when growing food in subsistence farming, and thus play an important part in securing their food supplies. One approach for reduction of pesticides, used particularly in sustainable concepts such as Cotton made in Africa, is integrated pest control. This can involve “threshold spraying”, i.e. not using preventive spraying, but spraying only if certain damage thresholds are exceeded, that is if the pest or pathogen attack is so serious that it is likely to cause economic damage. The damage threshold principle requires intensive training of farmers, but also permits reduction of pesticide use by up to 30%.

Cotton made in Africa is cultivated using sustainable methods by smallholder farmers in Benin, Zambia, Burkina Faso, Malawi and Cote d'Ivoire. Specifically that means that the cotton is grown in rain-fed cultivation with effective, responsible use of pesticides and fertilizer, and is harvested by hand. Cotton made in Africa has defined the requirements for growing in a Criteria Catalogue, and checks compliance by regular verification. Cotton made in Africa has undertaken not to grow any genetically modified cotton in the framework of the initiative, initially until 2011.

The Sustainable Cotton Project’s Cleaner Cotton ™ is a grower programme that helps move farmers through the changeover from chemically-dependent to more biological sound approaches. Composted manures and cover crops replace synthetic fertilizers; innovative weeding strategies are used instead of herbicides; beneficial insects and trap crops control insect pests; and alternatives to toxic defoliants prepare plants for harvest. Sustainable Cotton encompasses biologically-based, integrated pest management (IPM), and organic farming practices in the production, manufacturing and use of cotton.

Another organisation, the Better Cotton Initiative (BCI) aims to promote measurable improvements in the key environmental and social impacts of cotton cultivation worldwide to make it more economically, environmentally, and socially sustainable. The BCI aims to facilitate a solution for the mainstream cotton sector by developing a market for a new mainstream commodity: “Better Cotton”, which involves enabling farmers to grow and sell “Better Cotton” through minimising the harmful impact of crop protection practices, using water efficiently, caring for the health of the soil, conserving natural habitats, caring for and preserving the quality of the fibre, promoting “Decent Work”, and adopting better farm management practices, supported by activities that build effective producer organisations, improve access to finance and provide training which should also lead to improved productivity and an improved financial situation for farmers and cotton farm workers. The BCI concept of “Decent Work” is that originated by the International Labour Organisation (ILO) to describe work that provides opportunities for women and men to work productively in conditions of freedom, equity, security and human dignity.

Naturally coloured cotton fibres are agricultural fibres that are an alternative to conventional cotton. The fibre comes from the seed, is usually grown organically, and requires less processing than other cottons because it does not require dyeing or bleaching therefore avoids the impacts associated with colouration. Naturally pigmented cotton can be found in a variety of colours, ranging from beige, red, earth brown, chocolate brown , green, yellow, red, pink, and white. It is soft, resilient and absorbent, as well as biodegradable. There are a number of problems associated with these cotton varieties, such as short staple and fineness that has limited their appeal. A strain of brown cotton grown in India has overcome this by being woven into distinctive waffle textures, exploiting the yarns naturally twisted structure which does not need mercerisation.

Another cotton initiative is the use of certain enzymes traditionally used in the food and brewing industries which are increasingly being used in the processing of cotton for removing the sizing prior to dyeing and are best known for making denim production a cleaner and more environmentally friendly process. These enzymes can fade indigo colour to a pre-determined degree, and can also assist in cleaning the waste indigo dye water after dyeing. Experiments have been carried out to genetically engineer a blue colour into cotton by imparting a “blue” gene into the plant, with the aim of negating the necessity of indigo dye in denim products. This research remains “ongoing”, but the aim is to address the polluting effects of the traditional indigo dyeing process.

LiNEN
Organic linen is made from flax crops that have not been treated with toxic herbicides, fertilizer, fungicides or pesticides. Organic linen is made from flax that is grown in a sustainable manner, which means that the earth's resources won't be damaged or depleted in the growing of the plants. Flax generally requires minimal use of pesticides and relies only on rainfall for irrigation. It can be found in certified organic varieties, however, flax crops are often close to, or do, comply with organic standards, whether or not they are certified. Flax fibres are biodegradable, but are currently not recyclable.

Alternatives to the customary process of retting techniques such as dew retting, where plants are left to decompose on the ground with the right conditions of heat and moisture, or enzyme retting, in which enzymes are applied to the flax either in the fields or in the retting tanks, can be used, and avoid the pollution problems associated with the traditional method.

WOOL

wool
Image: Sheep by Suzi Potts

Organic wool is a safer alternative, whereby sheep are reared on organically grown feed and graze on land that is not treated with pesticides. The sheep are not dipped in synthetic pyrethoids or organophosphates (OPs), or injected with any hormones and are fed on organic substances (either grain or grasses not treated with pesticides) in the production of organic wool. Truly organic wool is not treated with chemicals through the entire production process from the farm to the end garment and processing must not include the typical bleaching and chemical processing used on conventional wool.  Organic wool also refers to the process of making the sheered wool fibre into a spun yarn and textile. The organic manufacture of wool is very sustainable, but in order to comply with certification programmes it is typically manufactured on a relatively small scale.

For many years, sheep producers around the world have maintained exotic, rare, and coloured breeds of sheep. Naturally coloured wool which is not dyed can be used for people with skin allergies and excludes the need to use chemical dyes, saving 70% of water.

Recycled wool is another sustainable fibre and refers to either fabric or product that has been regenerated for a second life cycle. The source of this wool can be cast-off material salvaged from the weaving and spinning process, scraps from clothing production, or post-consumer discarded material.

Alternative processing and aftercare methods include: chlorine-free and AOX-free alternatives which can be used to make machine-washable wool garments with next-to-skin comfort; a new “hyrdoentanglement” technique developed by Wooolscience and Canesis in the UK, using high pressure water jets, developed with the aim of reducing wool fabric production costs to a one step process; and Green Earth Cleaning, which is a new solvent and cleaning process based on liquid silicone, which can be used as an alternative to perchloroethylene for dry cleaning.

SILK
Peace, or ahimsa silk production cultivates silkworms in open forest, where there is an easy source of food, and uses no hazardous chemicals. The silkworm chrysalis is collected after the moth has emerged naturally, hence the term “peace” or sometimes “vegetarian” silk. Peace silk is of lower quality than cultivated silk and the fibres are shorter than regular silk as the moth damages the silk cocoon, breaking the continuous filament as it exits the chrysalis. Bleaching and degumming processes are not used in the treatment of peace silk; instead it is processed with non-toxic chemicals and natural processes to reduce waste.

In common with the rediscovery of forgotten strains of naturally coloured cotton, the Wild Silk Africa initiative in South Africa is developing a sustainable project in the North West province of the country in partnership with the Council of Scientific and Industrial Research (CSIR), creating a luxurious honey-coloured wild silk fabric derived from the cocoon of the Gonometa moth, whose worm feeds on the indigenous mopane tree.

Depending on how you feel about genetic modification, another initiative involves the experimentation of the genetic make-up of the silkworm to introduce new properties to the fibre, as Japanese scientists have bred a new type of silkworm that can produce extremely fine and much longer thread for use in the medical world for stitching wounds. A gene transplantation method takes the gene responsible for the fluro green colour in certain jellyfish and introduces it into female moths, resulting in green silk. This was the first step undertaken in breeding new varieties of moths resistant to diseases, as virus infections and other diseases can have catastrophic effects on the global silk crop.

VISCOSE
Viscose made from wood from sustainably managed forests and viscose produced without chlorine-containing bleach and zinc sulphate and which avoids catalytic agents containing cobalt or manganese are the safest alternatives.

Lyocell – Trade name Tencel™ is similar to viscose and uses pulp from eucalyptus trees, which are grown on sustainably run farms certified by the Forest Stewardship Council (FSC) and the fibre carries the Pan European Forest Council (PEFC) quality seal. The US Federal Trade Commission defines Lyocell as "a cellulose fabric that is obtained by an organic solvent spinning process". It classifies the fibre as a sub-category of rayon.

Lyocell uses a renewable raw material, is fully biodegradable - taking only six weeks in an aerated compost heap. It can be planted on marginal lands and does not require irrigation or pesticides. The wood pulp is processed in a non-toxic organic solvent (amine oxide) solution which is non-corrosive and all the effluent produced is non-hazardous. Up to 99% of the solvent can be recovered, purified and reused in a closed-loop spinning process that conserves energy and water. Lyocell requires no bleaching prior to processing as the fibre is already clean. Processing does not utilize any of the harmful chemicals (like formaldehyde) sometimes used to treat the fibrillation of these fibres.

The negatives however, are that production is energy intensive and the fabric tends to crease and “fibrillate” in the wet state, creating a “fuzzy, or peach-skin” effect.

POLYESTER
Alternatives to conventional polyester are made without catalytic agents containing cobolt or manganese salts and those that avoid based catalysts.

Recycled polyester reduces the strain on natural resources by salvaging waste-bound polyester rather than using newly sourced petro-chemicals and can be created from items such as mineral water bottles, coffee cups and coat hangers. Its production saves over half a million barrels of oil and eliminates 400,000 tons of harmful emissions which contribute to global warming, acid rain and smog. Recycled polyester was first put into use by Patagonia in the 1990's in conjunction with Teijin Limited, who produce a patented version called Eco Circle. Since then, recycled polyester has gained in popularity and there are, now, many patents for, and constructions of, recycled polyester. It also reduces non-biodegradable waste.

NYLON
Recycling nylon reduces the strain on natural resources by salvaging post-industrial waste fibre and yarn rather than using newly sourced petro-chemicals. Recycled nylon requires less energy and creates less CO2 pollution than virgin nylon. Recycled nylon also reduces discards and incinerator emissions and is recyclable again at the end of its life.

LEATHER
leather
Image: Cows by Suzi Potts

Leather look-alike items made with polyurethane (PU) are considered safe.

 

 







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