How we make and buy clothes is hurting the planet. Here's a solution.

Have you ever considered the environmental cost of your favorite pair of jeans? And what about the clothes that hang in your closet unworn? 

The impact of apparel manufacturing on the Earth's climate is certainly on the minds of executives at athletic wear company Lululemon, which is choosing Earth Day this year to launch a resale program to take back worn garments from customers and sell them at a discount. The goal: keep clothes in circulation longer, limiting Lululemon's carbon emissions by reducing unnecessary production and consumption by consumers.

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Lululemon isn't the only major retailer to dip its toes into the resale or consignment market in an effort to be more eco-friendly. 

Arc'teryx, Levi's, REI, Madewell, Michael Stars, The North Face and Tommy Hilfiger are among the hundreds of mainstream brands that are working to extend the lifecycles of their garments by using more sustainable materials, recycling and reusing fabrics, and reselling used apparel.  

Womenswear brand Eileen Fisher is a leader in sustainable fashion. Since 2009, the company has taken back 1.8 million pieces of its own clothing and recycled, reused or resold it. 

"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. 

2,400 gallons of water for one pair of jeans

As climate change intensifies, experts say it is critical to rethink how we produce clothing in order to decarbonize apparel manufacturing. The garment industry is one of the most pollutive in the world, accounting for an estimated 10% of global greenhouse gas emissions — more than all international flights and maritime shipping combined, according to a 2019 World Bank report. 

By another measure, in 2018 the sector produced more than 2 billion metric tons of greenhouse gas — about 4% of the global total, research from consultancy McKinsey & Company shows. 

Water consumption is another issue. Every year, the fashion industry uses 93 billion cubic meters of water, according to the Ellen MacArthur Foundation. It can take nearly 2,400 gallons of water to make a single pair of jeans.

Traditional manufacturing processes often deplete the planet of natural resources, consume immense energy and water, and use chemicals that are harmful to the environment. But the damage doesn't stop there. After consumers use and discard products, they end up in landfills.  

"Our closets are too filled"

Manufacturers make more clothing than shoppers can reasonably buy and wear. An estimated 9 billion items of clothing mostly sit unworn in U.S. consumers' closets every year, according to ThredUp, the largest online thrift and consignment store.

That's no surprise given that most companies' business models count on boosting production and sales every year.

"We're buying too much clothing, our closets are too filled," said Peggy Blum, author of Circular Fashion: A Supply Chain for Sustainability in the Textile and Apparel Industry. "It's not about what brands are doing — there is no way anyone can be 100% sustainable or create no impact. The only way to create no impact is not to produce and not to consume, but we don't operate that way."

Although many companies are taking steps to reduce their carbon emissions on a per-product basis, experts say that's not good enough given that their goal is still to keep increasing sales.

"The biggest hurdle to reducing carbon emissions or climate science-based goals is the increase in sales every year," said Lynda Grose, a pioneer of sustainable fashion design and professor at California College of the Arts. "The reason for that is the industry for the last 30 years or more has been focused on selling more and more product."

"Because so many people's jobs and fortunes are tied to the fashion industry, I don't see it slowing down. I don't see it making less product," said Elizabeth Cline, author of The Conscious Closet: The Revolutionary Guide to Looking Good While Doing Good, and director of advocacy and policy at nonprofit group Remake.

Even outdoor clothing and gear maker Patagonia — which is known for repairing and recycling its customers' used clothing and which has long been committed to using sustainable materials — acknowledged in its 2019 Benefit Corporation Report that these efforts alone were insufficient.

"We are working toward becoming a carbon-neutral company across our supply chain, but even as we make significant advances, such as the increased adoption of recycled materials, our footprint is increasing due to our growth of sales," the company said. 

Three years ago Patagonia launched its "Worn Wear" program to take back used clothing from the brand in exchange for store credit. The company says it believes "the best way to reduce the environmental and carbon footprint of your clothes is to keep them in use longer."

Secondhand market expected to double

That philosophy is picking up steam. A number of other prominent brands, from luxury fashion designer Stella McCartney to sportswear brand Adidas, have entered the resale space and now allow customers to return their used garments. New customers may then buy these used goods at a discount either directly through the retailer as well as through resale websites such as ThredUp or TheRealReal, a luxury online and brick-and-mortar consignment shop. 

The value of the secondhand market, including resale and traditional clothing donation, is projected to double in the next five years to $77 billion, according to ThredUp's 2021 Resale Report. Keeping garments in circulation longer also promises to open up new revenue streams for brands whose business models have long been predicated on producing and selling more clothing every year to turn up profits. 

"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 annualreport. In other words, that's how many items customers purchased used instead of new. 

"The natural conclusion from that is the world produced half a billion items we probably didn't need in 2020. So it's another data point on how overproduction is a real problem," Reinhart said.

Beyond reducing carbon emissions, experts say a thriving clothing resale business could also help companies acquire new customers.

"Over the next five years as younger people gain more purchasing power, I think it's critical that brands figure this out," Reinhart said. "People who are now in their teens and 20s are natives of resale — this is part of their experience. I think brands are smart to figure this out now." 

Cline also thinks the resale market holds a lot of promise both for brands and the environment.

"Resale is the success story. Who could have imagined that wearing secondhand would become so mainstream? So many brands are doing more with recycled garments," she said. "Re-use in general is really promising and it's good for the industry. They'll keep making new stuff, but at least we're reusing things that are already out there and not relying so much on virgin resources."