The Future of Blue Jeans is Green

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.

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

The fabric jeans are made from can make jeans environmentally unfriendly . Cotton is a crop that needs a lot of water. Farmers need about 1,800 gallons of water to grow enough cotton for one pair of jeans. Many are made from a blend of cotton and petroleum-based materials. These are great for fit and stretch but are hard to recycle, McClendon says.

Another reason is the dying process. Blue jeans first got their color from the plant Indigofera. Most modern jeans get their color from synthetic indigo dye. The dye is made from a mix of chemicals. One of those is formaldehyde. This chemical is also used to preserve dead tissue. Exposure to high levels of formaldehyde can cause health problems and some cancers. The fabric must also be treated with more chemicals to hold the color. These can pollute waterways when denim producers wash out the dye.

Finally, manufacturers wash jeans many times. This turns the stiff denim into soft fabric. The process is called stone-washing. Almost every denim product on the market is stonewashed, says McClendon. 

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.

One pair of jeans requires more than 2,600 gallons of water by the time they’re sold at stores. The denim industry uses more than 45,000 tons of synthetic indigo a year. It also uses hundreds of thousands of other chemicals.

These can turn riversblue or pink near textile industries, says Raha Saremi. She’s a scientist at the University of Georgia. Many countries like the U.S. prohibit this kind of pollution. In others, environmental laws aren’t as strict. Toxic pollution there creates health issues for workers and people who live near the rivers.

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.”

Scientists like Saremi are inventing environmentally friendly jeans. Her team is working on a new indigo dye technology. They use wood pulp from agricultural waste to create a microscopic substance.

“These tiny particles can absorb a lot of dye,” says Saremi. “We coat this material on fibers, yarns, and fabrics.” The natural and sustainable process uses 90 percent fewer chemicals. It also uses 90 percent less wastewater, Saremi adds.

Clothing brands and denim makers are also developing new technologies. The company Wrangler swapped water for a foam to apply dye. The process uses about 60 percent less energy. Levi Strauss & Co. reduces water waste with a different finishing process. The company breaks in jeans using a small amount of water and the molecule ozone. Another way to make jeans looks distressed? Tumble them with bottle caps and golf balls. It uses no water at all!

The surge in green solutions for denim shows a fashion industry becoming more environmentally conscious, 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.”