I'm currently researching for a project and was wondering if you guys might be able to help me?

I need to know the weight of C02 emissions produced in the life cycle of a pair of jeans. I can't seam to find this information anywhere and would really appreciate a little help!

Many thanks
Jo

Well Jo, we'll do the best we can to help you out. While figuring out the carbon emissions of your travel or home energy use isn't a difficult task (several sites such as TerraPass offer calculators to assist in the task), nobody seems to have a definitive calculator for calculating the carbon footprint of what you wear. However, we did find some information regarding what it takes to create a pair of jeans and one study that examined the life cycle of a pair of jeans. 

The average American owns 1.5 pairs of jeans; women are the biggest offenders of all when it comes to denim, with the average female owning eight pairs of jeans. And while picking out that perfect pair may seem like a complicated task in itself, there's actually a whole process involved well before the jeans reach the store shelves. For starters, cotton crops require a lot of water - approximately 1,500 gallons of it are required to grow the cotton used to make just one pair of jeans. Then there's the necessary equipment to harvest the cotton, which takes about one pound of oil to operate.

Once the cotton is picked and harvested, the resulting cotton yarn is processed using starch, paraffin (which also comes from oil) and occasionally caustic soda to provide that popular worn look. Starch is biodegradable, but can be harmful to the earth when dumped in the water supply, since the same microbes that biodegrade it also consume oxygen, which in turn may be detrimental to the creatures that call that water home. The yarn is then dyed using synthetic indigo, which is also produced from coal or oil. In rare circumstances, a factory may be procese in measuring the concentration of dye and then be able to re-use the liquied by adding fresh dye, however in facilities where deinm is produced at a low-cost, protecting the earth is not a priority, so the dye may also be dumped in the water supply.

If you want to know just how harmful these dyes can be, look to the case of Tehuacan, Mexico, once a city known for its mineral springs and spas. In the 90's it became a central location for denim production, used by many top North American labels. Now the city's canals are stained a bright blue from the dyeing of fabric. The area's residents must also deal with the effects of dealing the constant barrage of chemicals and processes including sandpapering, fading using potassium permanganate, stonewashing and fabric softening.

One popular denim trend that never seems to go out of style is the distressed look, which is achieved by stonewashing. Stomewashing involves washing and rinsing a pair of jeans several times (which of course uses more water and energy), then sandblasting and scrubbing jeans which releases denim and silica dust into the air.

These facts demonstrate just how hard the production process of one pair of jeans is on the earth. Yikes! It certainly makes you think twice about heading into Gap for the latest must-have pair. If you really want some new denim, hit your local thrift store to pick up a used pair; that way, if you love the worn-in look but are distressed (haha, get it) about the environmental impact this creates, you can always try the DIY approach to destroying your denim. You'll spend less money too! And check back Friday as we examine the environmental impact of the life cycle of a pair of jeans more specifically.

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