Did you ever wonder why your jeans are blue? Natural denim is beige or ecru, and back in the day, to get blue jeans, indigo dye from the leaves of the indigo plant was used.

Then, a synthetic dye was made to yield faster, more predictable results compared to its natural counterpart. But making a pair of jeans now isn't as naturally geared; more so exploitative.

Creating a pair of jeans from scratch requires an alarmingly large amount of natural resources, including fresh water; making denim the most environmentally damaging materials out there. The synthetic indigo dye, which is used to dye one billion pairs of jeans per year is incredibly toxic. Mordant, petroleum, potassium permangate, formaldehyde and even cyanide go into making jeans that you wear.

At the source of where the jeans are made, whether in China, India or Pakistan; these areas are known to make the vast majority of the world's jeans, their water waste is unregulated. As a direct consequence of this, all of these chemicals get washed into rivers where their fresh water supply becomes contaminated.

The water can become so toxic from the dyes, that a few years ago, India's street dogs turned blue. There are now some companies that are changing the way jeans are processed, using less water and safer methods. The change of attitude towards fast fashion still needs work and it all starts with you.

In order to slow down fast fashion, keeping rivers clean and provide better working environments for garment employees, we recommend you buy second-hand jeans. Denim is incredibly long lasting and can endure labour intensive jobs, so it's best to keep it circular for as long as you can.

Preworn supplies these jeans brands for top quality denim and long term investment:

We recommend Levi's and Wrangler as they are leading the way to becoming more responsible for their garment production, investing in alternative materials and even supporting second-hand.

The most sustainable thing you can do is to mend and repair your clothes. The trend to keep clothes circular is growing and there are hundreds of videos like this one.


And because we want jeans to stay sustainable, we have a few tips on how to keep them lasting longer.

  • Turn your jeans inside out. This protects the fibres and helps prevent fading.
  • Use a mild detergent. Use fabric softener specifically for dark washes.
  • Try not to over-wash. Once every six weeks or every 3 - 4 wears.
  • Wash on a cold temperature on a gentle setting. This helps prevent shrinking.
  • Hand washing is the best method. Cold water, do not ring, let it dry naturally


If you'd like to know more about indigo dye and blue dogs, we recommend this article by Slow Fashion Movement. It'll take you down a rabbit hole and hopefully make you think twice before throwing out any jeans.

Let's make the change together, shop Preworn.

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