A number of clothing companies have launched programs to keep their clothes in circulation for longer and reduce their carbon footprint.

Hundreds of mainstream brands are working on achieving this goal through a number of ways, such as using more sustainable materials, recycling and reusing fabrics, and reselling used apparel.

"The point is to be completely responsible for our product all throughout its lifecycle," said Lilah Horwitz, the head of Eileen Fisher's take-back program. The company has, since 2009, taken back 1.8 million pieces of its clothing and recycled, resold, or reused them.

As for the garment industry's carbon footprint, it is estimated to be one of the world's most pollutive industries, as it is estimated to account for nearly 10% of global greenhouse gas emissions.

The fashion industry also uses up a lot of water, with 93 billion cubic meters being used every year by the industry. Nearly 2,400 gallons of water are needed to make a single pair of jeans.

Secondhand market

One of the ways companies are trying to keep their clothes in circulation for longer is to take back their used clothing to enter the resale space. That way new customers can buy used garments at a discount either through the retailer or resale websites.

"Branded resale is a trend that is accelerating, and it remains to be seen how companies invest in it and how the math shakes out for them to ultimately produce less," ThredUp co-founder and CEO James Reinhart told CBS MoneyWatch. 

To date, secondhand retail has displaced more than half a billion items of apparel that otherwise would have been purchased new in 2020, according to ThredUp's annual report. In other words, that's how many items customers purchased used instead of new.