Cotton
Abundance
In 2011, over 112 million bales of cotton were produced world wide, with the top three countries (China, India, and the United States in that order) producing 70% of the world's cotton [1]. In the United States alone, 12 million acres (about 19,000 sq miles) are devoted to cotton fields. This yields an average harvest of about 7.3 billion pounds of cotton [2]. Of this harvest, 75% goes to apparel, with only 18% to home furnishings, and 7% to industrial products. Cotton has always been the leading natural fiber, but with the rise of synthetic materials, it has plummeted to account for only about 39% of the world's fibers today [3].
History
Just prior to WWII, cotton made up 81% of global fiber consumption [2]. Then in the mid 20th centuries, synthetic fibers burst onto the fabric scene and cotton usage dropped to 75%. By 1970, cotton accounted for only 57% of the world's fiber consumption, and today that percentage has dropped to about 39% [3].
So what did cotton consumption look like before the 20th century? As it turns out, cotton has somewhere around 9,000 years of history in fashion [4]. Cotton cloth was found in caves of Mexico dated to at least 7,000 BC, while in the Indus River Valley and Nile valley cotton was being harvested and woven since at least 3,000 BC. It wasn't until 1500 that cotton was known virtually throughout the world.
It wasn't until the industrial revolution came to the textile industry in England and advent of the cotton gin in America that the cotton industry really took off. To illustrate just how much mechanization of cotton production and processing drove the industry, consider the fact that in the span of one decade, the value of the US cotton industry rose from $150,000 to over $8 million [4].
Manufacturing
We have come a long ways from harvesting and processing cotton by hand. Nowadays, the process is almost entirely mechanized in countries like the US, Australia, and most of Europe [5].
1) Machines typically plant 12 rows of cotton seeds at a time at some point during the spring. This time varies from year to year, and from place to place. The seed grows, flowers, and produces a pod, called a boll, full of cotton in just 2-3 months.
2) Once the boll has split open to reveal its load of cotton, it is allowed to dry in the sun. The leaves of the cotton plants are then chemically removed, or in some areas, freezing temperatures cause the plant's leaves to fall off naturally.
3) Once the leaves are gone, cotton harvesting machines blow high pressured air over the bolls to collect the cotton (this method varies, but the US typically uses this air blowing technique).
4) The harvested cotton is then pressed into modules, each weighing about 20,000 pounds, and shipped to the gin.
5) At the gin, cotton is cleaned of all dirt, lint, and sticky seeds and pressed into 500 pound bales for shipment.
6) Once arriving at the textile mill, the raw, clean cotton is cleaned again with blowing and beating. Remaining fibers 1-1.75 inches long are then used for textiles.
7) These fibers are then combed by a carding machine, straightening them into soft, untwisted rope known as a sliver.
8) Slivers are then fed into spinning frames that twist to form yarn.
9) Looms weave the cotton yarns into fabrics much the same way traditional hand-weaving frames did, by interlacing length-wise yarns (warp) and crosswise yarns (filling). The primary difference being the speed at which modern yarns are interlaced.
10) When the fabric has been made, it is then sent to yet another location where it is bleached, pre-shrunk, dyed, printed, and given a last chemical finish. These processes vary depending on the desired feel of the final product. Denim, fleece, business suits, blouses, and comfy pajamas can all be made from cotton, but variations on the final stages of processing drastically change the properties of the ultimate fabric.
In 2011, over 112 million bales of cotton were produced world wide, with the top three countries (China, India, and the United States in that order) producing 70% of the world's cotton [1]. In the United States alone, 12 million acres (about 19,000 sq miles) are devoted to cotton fields. This yields an average harvest of about 7.3 billion pounds of cotton [2]. Of this harvest, 75% goes to apparel, with only 18% to home furnishings, and 7% to industrial products. Cotton has always been the leading natural fiber, but with the rise of synthetic materials, it has plummeted to account for only about 39% of the world's fibers today [3].
History
Just prior to WWII, cotton made up 81% of global fiber consumption [2]. Then in the mid 20th centuries, synthetic fibers burst onto the fabric scene and cotton usage dropped to 75%. By 1970, cotton accounted for only 57% of the world's fiber consumption, and today that percentage has dropped to about 39% [3].
So what did cotton consumption look like before the 20th century? As it turns out, cotton has somewhere around 9,000 years of history in fashion [4]. Cotton cloth was found in caves of Mexico dated to at least 7,000 BC, while in the Indus River Valley and Nile valley cotton was being harvested and woven since at least 3,000 BC. It wasn't until 1500 that cotton was known virtually throughout the world.
It wasn't until the industrial revolution came to the textile industry in England and advent of the cotton gin in America that the cotton industry really took off. To illustrate just how much mechanization of cotton production and processing drove the industry, consider the fact that in the span of one decade, the value of the US cotton industry rose from $150,000 to over $8 million [4].
Manufacturing
We have come a long ways from harvesting and processing cotton by hand. Nowadays, the process is almost entirely mechanized in countries like the US, Australia, and most of Europe [5].
1) Machines typically plant 12 rows of cotton seeds at a time at some point during the spring. This time varies from year to year, and from place to place. The seed grows, flowers, and produces a pod, called a boll, full of cotton in just 2-3 months.
2) Once the boll has split open to reveal its load of cotton, it is allowed to dry in the sun. The leaves of the cotton plants are then chemically removed, or in some areas, freezing temperatures cause the plant's leaves to fall off naturally.
3) Once the leaves are gone, cotton harvesting machines blow high pressured air over the bolls to collect the cotton (this method varies, but the US typically uses this air blowing technique).
4) The harvested cotton is then pressed into modules, each weighing about 20,000 pounds, and shipped to the gin.
5) At the gin, cotton is cleaned of all dirt, lint, and sticky seeds and pressed into 500 pound bales for shipment.
6) Once arriving at the textile mill, the raw, clean cotton is cleaned again with blowing and beating. Remaining fibers 1-1.75 inches long are then used for textiles.
7) These fibers are then combed by a carding machine, straightening them into soft, untwisted rope known as a sliver.
8) Slivers are then fed into spinning frames that twist to form yarn.
9) Looms weave the cotton yarns into fabrics much the same way traditional hand-weaving frames did, by interlacing length-wise yarns (warp) and crosswise yarns (filling). The primary difference being the speed at which modern yarns are interlaced.
10) When the fabric has been made, it is then sent to yet another location where it is bleached, pre-shrunk, dyed, printed, and given a last chemical finish. These processes vary depending on the desired feel of the final product. Denim, fleece, business suits, blouses, and comfy pajamas can all be made from cotton, but variations on the final stages of processing drastically change the properties of the ultimate fabric.
Environmental Impacts
While many tout cotton as a wonderfully eco-friendly fabric, this is sadly not the case. While more sustainable than many synthetic fibers, cotton demands the most water of any fabric on the planet, requiring over 210,000 billion liters of water annually [6]. Not only does this put a strain on farmers, but this puts an incredible strain on the surrounding ecosystem.
However, the unbelievable amount of pesticides and insecticides used by most cotton farmers does the most damage. In fact, cotton is known as the world's "dirtiest" crop because it has the largest pesticide to land ratio of any single major crop. Though it only comprises 2.5% of the world's cultivated land, it uses 16% of the world's insecticides, herbicides and defoliants [7] [8]. This brings us to the controversial GMO, Bt cotton. Bt cotton produces a toxin found in the bacterium Bacillus thuringiensis (Bt), harmful to larvae of various bug species that destroy cotton crops, but harmless to other forms of life [9]. This endogenous toxin eliminates the need for many other pesticides, and because it can take almost .35 pounds of synthetic fertilizers to grow enough cotton for a single t-shirt, this could dramatically benefit ecosystems surrounding these Bt cotton fields [10].
Unfortunately, even if cotton were to be harvested organically and without causing a strain on water availability in surrounding environments, the dyeing and finishing is still a major ecological factor. To transform raw cotton into the clothes we wear today, many hazardous chemicals are often added. These include, but are in no way limited to, silicone waxes, petroleum scours, softeners, heavy metals, flame and soil retardants, ammonia and formaldehyde [10]. The harmful effects are seen downstream, when water used to rinse the clothes is literally swept downstream, destroying aquatic life or seeping into ground water and surrounding habitat, drastically altering ecosystems in these areas with minimal filtering.
What You Can Do
When buying cotton, try to buy organic cotton whenever possible to minimize the far-reaching effects of pesticide contaminants. But better yet, don't buy clothes until your old ones wear out, and don't buy more clothes than you need. All clothes take a toll on the environment, no matter how eco-friendly they seem.
While many tout cotton as a wonderfully eco-friendly fabric, this is sadly not the case. While more sustainable than many synthetic fibers, cotton demands the most water of any fabric on the planet, requiring over 210,000 billion liters of water annually [6]. Not only does this put a strain on farmers, but this puts an incredible strain on the surrounding ecosystem.
However, the unbelievable amount of pesticides and insecticides used by most cotton farmers does the most damage. In fact, cotton is known as the world's "dirtiest" crop because it has the largest pesticide to land ratio of any single major crop. Though it only comprises 2.5% of the world's cultivated land, it uses 16% of the world's insecticides, herbicides and defoliants [7] [8]. This brings us to the controversial GMO, Bt cotton. Bt cotton produces a toxin found in the bacterium Bacillus thuringiensis (Bt), harmful to larvae of various bug species that destroy cotton crops, but harmless to other forms of life [9]. This endogenous toxin eliminates the need for many other pesticides, and because it can take almost .35 pounds of synthetic fertilizers to grow enough cotton for a single t-shirt, this could dramatically benefit ecosystems surrounding these Bt cotton fields [10].
Unfortunately, even if cotton were to be harvested organically and without causing a strain on water availability in surrounding environments, the dyeing and finishing is still a major ecological factor. To transform raw cotton into the clothes we wear today, many hazardous chemicals are often added. These include, but are in no way limited to, silicone waxes, petroleum scours, softeners, heavy metals, flame and soil retardants, ammonia and formaldehyde [10]. The harmful effects are seen downstream, when water used to rinse the clothes is literally swept downstream, destroying aquatic life or seeping into ground water and surrounding habitat, drastically altering ecosystems in these areas with minimal filtering.
What You Can Do
When buying cotton, try to buy organic cotton whenever possible to minimize the far-reaching effects of pesticide contaminants. But better yet, don't buy clothes until your old ones wear out, and don't buy more clothes than you need. All clothes take a toll on the environment, no matter how eco-friendly they seem.