Natural textile fibers
Natural fibers are those fibers that come from natural sources, like animals and plants, and do not require fiber formation or reformation. Several vegetable fibers were used by prehistoric people, like hemp, which is presumably the oldest cultivated fiber plant. Natural fibers from vegetable fibers are obtained from different parts of the plants. These fibers can be categorized into three types depending on the part of the plant from which they are extracted: stem fibers (jute, mesta, banana etc.), leaf fibers (sisal, pineapple, screw pine etc.) and seed fibers (cotton, coir, old palm etc.). These are the most common natural fibers:
Cotton: Cotton is the most used textile fiber in the world (25 million tonnes produced worldwide per year) and is plentiful and economically produced, making cotton products relatively inexpensive. The fibers can be made into a wide variety of fabrics ranging from lightweight voiles and laces to heavy sailcloths and thick-piled velveteens. Cotton fabrics can be extremely durable and resistant to abrasion and it is comfortable to wear because it absorbs and releases moisture quickly. Because cotton accounts for more than half of all fiber needs across the globe, cotton growers use artificial means and excessive use of pesticides to make cotton grow faster. This means that regular cotton products are usually full of chemicals that can cause allergic reactions to the skin. Furthermore, the pesticides damage the environment and disturb the ecological balance. The cultivation of conventional cotton uses 22.5% of the world's insecticides and 10% of the world's pesticides. Organic cotton on the other hand is grown from non-GMO seeds, and no insecticides, pesticides, fungicides and herbicides are used in the growing process. Other differences include:
- organic cotton is handpicked vs machine picked for regular cotton resulting in more pure, softer and more durable cotton
- regular cotton is grown on the same soil over and over again, degrading the soil quality, removing nutrients, and leading to unhealthy crops. Since these crops require more water, they are irrigated heavily, resulting in water wastage. Organic cotton is rotated from one soil to another, and the nutrients retain water for long, requiring less irrigation. This leads to healthier crops.
- processing of regular cotton uses a large amount of chemicals. The use of heavy metals, chlorine, and chemicals dyes are frequently used in the manufacturing of regular cotton. Even after washing the finished products, the residue of these chemicals remains and can cause serious skin allergies. Organic cotton uses safer alternatives to chemical dyes and whiteners. Natural or water-based dyes, peroxide for whitening, and other safer products are used to manufacture the finished goods.
Bamboo: Even though bamboo as a plant can be sustainable (it grows rapidly and naturally without the use of pesticides, herbicides or fertilizers), the fibers made out of bamboo may not be. There are two ways to process bamboo from the plant into a fiber, mechanically or chemically. In the mechanical process the woody parts of the bamboo plant are crushed and the natural enzymes break down the bamboo walls into a mushy mass. Then the fibers can be combed out and spun into yarn (like linen is produced from flax). This bamboo is also called bamboo linen. When using the chemical process, the bamboo is cooked in chemical solvents like sodium hydroxide (NaOH – also known as caustic soda or lye) and carbon disulfide in a process also known as hydrolysis alkalization combined with multi-phase bleaching. Both sodium hydroxide and carbon disulfide have been linked to serious health problems. This is basically the same process as used to make rayon from wood and hence this type of bamboo is also called bamboo rayon. So, when choosing bamboo products be aware of these two types of bamboo fibers.
Linen: Linen is made from the cellulose fibers that grow inside of the stalks of the flax plant that uses considerably fewer resources than the cotton plant (like water, energy, pesticides, insecticides, fertilizers). Flax can grow in poor soil which is not used for food production. In some cases, it can even rehabilitate polluted soil. Furthermore, flax plants have a high rate of carbon absorption. is strong, naturally moth resistant, and when untreated (i.e. not dyed) it is fully biodegradable. It is a natural insulator keeping you warm in the winter and cool in the summer. Although linen has many benefits, it is not being used as a primary fiber for clothing because it is very labor intensive to produce linen making it a higher priced commodity, and considered among many to be a ‘luxury’ fabric.
Flax is an annual plant, which means it only lives for one growing season. From seed-planting, it is ready to be harvested in about a hundred days. To make linen, the plant needs to be pulled from the ground as some of the most valuable parts of the plant are in the lower stem and roots. After harvest, flax stalks are set to dry in open air for several weeks and then the seeds are removed from the stalks. The stalks with roots attached are soaked in tanks of water, open ponds or running river water until the green part rots away (to be able to remove the fibers from the stalks by breaking down the sticky protein called pectin that holds them together; a process called retting). Retting can also be done much faster using mechanical turning or by using chemicals (alkali or oxalic acid) that are polluting if not neutralized before being released into water supplies. (alkali or oxalic acid). After the retting the fibers are spun into yarn and woven into linen.
Wool: Wool grows on sheep just like hair grows on humans. The best wool comes from Australian Merino sheep. Lambswool comes from the first fleece sheared from a lamb and produces the softest and finest wool fibers. In the traditional manufacture of wool the sheep are kept in large herds on small plots of land. This usually leads to overgrazing of the fields, leaving the sheep more susceptible to disease and infection. So, pesticides, insecticides and vaccinations are used that are moderately toxic to humans, amphibians, birds, and the sheep themselves. If these insecticides are not managed properly they can cause harm to human health, pollute streams, ground water, and drinking water from runoff.
In short, conventional wool is far from being as eco-friendly as we would expect. Certified organic wool guarantees that pesticides and parasiticides are not used on the pastureland or on the sheep theselves, and that good cultural and management practices of livestock are used. But certified organic wool is still pretty rare on the market and GOTS seems to be the only organization certifying organic wool.
Silk: Silk is produced by silkworms, caterpillars of several species of moth, the most important being the Bombyx mori which lives in mulberry trees. The silk comes from the caterpillar’s chrysalis, or cocoon. Cultivated silk comes from silkworms raised in production facilities where the worms are killed before leaving the cocoons as moths in order to prevent damage to the cocoons. It takes a silk worm 3-4 days to spin a cocoon around itself, which is made out of a single continuous thread which can be up to 1 kilometer in length. The fibers are extracted by steaming the cocoons or boiling them alive in order to preserve the entire spun cocoon. Because of this method, animal rights advocates prefer “Peace Silk”, Tussah or Ahimsa silks which allow the moth to evacuate the cocoon before it is boiled to produce silk.
After extracting the fibers, detergents are used to clean and bleach them, in order to loosen the gum and give access to the thread. The waste water is usually discharged to ground water, being a low level pollutant. The mulberry trees need fertilizers and pesticides applications. The worms are very sensitive to poisoning by agrochemicals and other inputs, so a supply of clean air and careful climate control are needed to guarantee maximum yields.