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The Future of Blue Jeans is Green

Blue jeans have evolved over the past 150 years and are getting better for the environment!

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It takes up to 2,600 gallons of water to make a single pair of blue jeans.

Whether skinny or baggy, distressed or deep navy, there’s nothing like your favorite jeans. These classic pants are a staple in many people’s wardrobes. But before the explosion of various fits and hues, denim began as a durable workwear garment more than 150 years ago. “It was considered a fabric of labor,” says Emma McClendon. She teaches fashion studies at St. John’s University in New York City.

In 1873, businessman Levi Strauss and tailor Jacob Davis patented the look we know today. Their company, Levi Strauss & Co., introduced the metal rivets, top stitching, and five-pocket configuration—“design features that are so recognizable to us,” says McClendon. By the 1950s, Hollywood’s jean-clad movie stars propelled denim to new heights. “This is when denim starts becoming associated with American identity, pop culture, film, and fashion.”

How Blue Jeans Get Blue
Watch a video about the history of blue jeans and the process of making them.

Blue Jeans 101

Today, people worldwide buy more than 2 billion pairs of jeans each year. Nearly two out of three people wear denim at least three times a week. But each pair comes with a cost to the environment. The fashion industry is one of the biggest polluters in the world, and denim is a significant contributor.

The environmental cost begins with the fabric’s source: cotton. It’s a thirsty crop. Farmers need about 1,800 gallons of water to grow enough cotton for one pair. On top  of that, many jeans are made of a mix of materials. Many are blended with petroleum-based fibers. These fibers are great for fit and stretch but are harder to recycle, McClendon says.

Blue jeans first got their color from indigo, which comes from the plant Indigofera. Most modern jeans are dyed with synthetic indigo. This dye uses a mix of chemicals, including formaldehyde, which is used to preserve dead tissue. Exposure to high levels of formaldehyde is known to cause health problems and some cancers. Plus, for the fabric to hold the dye, it must be treated with more chemicals. After the excess dyes are washed out, these chemicals can pollute waterways.

Finally, the jeans are washed many times to turn stiff, raw denim into soft, broken-in fabric. “Virtually every denim product on the market is stonewashed,” says McClendon.

Greener Jeans?

By the time a pair of jeans hits store shelves, more than 2,600 gallons of water have been used. The denim industry uses more than 45,000 tons of synthetic indigo a year—in addition to hundreds of thousands of other chemicals.

“It’s why you see those pictures of rivers turning blue or pink near textile industries,” says Raha Saremi, a materials scientist at the University of Georgia. Many countries—including the U.S.—have environmental regulations that prohibit this kind of pollution. But in the countries that allow it, the pollution from denim factories is toxic and creates health issues for workers and people who live near the rivers.

Photo of a person spraying painting jeans

Philip Cheung

To save water, some companies are switching to spraying dye onto jeans instead of soaking them in vats of dye.

Better Denim

Scientists like Saremi are inventing new ways to make jean production more environmentally friendly. Her team at the University of Georgia is developing a new “green” indigo dye technology. By reusing wood pulp from agricultural waste, they created a type of nanocellulose. This microscopic substance contains cellulose, a building block of plant cells that helps them stay firm.

“These tiny particles can absorb large amounts of dye,” says Saremi. “We coat this material on top of fibers, yarns, and fabrics.” This natural and sustainable material is already showing promising results. “Through this process, we use 90 percent less chemicals, and consequently we have 90 percent less wastewater,” Saremi adds.

Clothing brands and denim manufacturers have also been investing in new sustainable technologies. The company Wrangler partnered with Texas Tech University and a Spanish fabric mill to swap water for a foam that applies dye to yarns. This process uses about 60 percent less energy. Levi Strauss & Co. is also committed to reducing water waste with its Water-Less finishing process. One method uses just a small amount of water and ozone (a molecule of three oxygen atoms bonded together) to break in the jeans. Another way to make jeans looks distressed is to tumble them with bottle caps and golf balls, which uses no water at all!

The recent surge in green solutions for denim is a sign that the fashion industry is working toward a more environmentally conscious future, says Saremi. “I think sustainability is a very important issue for the fashion and textile industry,” she says. “It’s going to take some time, but I’m very hopeful.”

Ape Audit: Analyzing Populations with Percent Change
Watch this video about percent change

Calculate the percent change to see how the popularity and demand for jeans has shifted over time. Round answers to the nearest percent. Record your work and answers on our answer sheet.

In 2018, the estimated total value of the worldwide jeans market was $100 billion. By 2023, that global valuation is projected to rise to $128 billion. What would be the percent change?

Most denim manufacturing occurs in Asian countries. In 2013, the Asia Pacific region produced 3.8 million meters of denim, which increased to 4.0 million meters in 2015. What was the percent change?

A 2010 survey found that men and women paid on average $33 for a pair of jeans. In 2020, women’s average spending on jeans went up to $35, while men averaged $53 per pair. What is the percent change in average spending on jeans for women? For men?

A. During the pandemic, people bought fewer jeans. Levi Strauss & Co. had $5.8 million in sales in 2019. This dipped to $4.5 million in 2020. What was the percent change?

B.  The jean brands Lee and Wrangler combined made $2.4 billion in sales in 2019 and $2 billion in 2020. What was the percent change?

In which of the four cities on the chart were raccoons at the greatest percent of sites?

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