This article is part of our new series of Currents, which examines how rapid advances in technology are changing our lives.

Sustainability in the fashion industry was once the focus of only a few designers like Stella McCartney and outdoor gear companies like Patagonia.

However, traditional and emerging brands are trying to improve a supply chain that is increasingly being criticized for contributing to landfills and causing other forms of pollution throughout the manufacturing process.

From collaborating on making bio-fiber to making eco-friendly label attachments, some in the apparel sector are partnering with tech startups to clean up the world’s closets.

The biggest problem is the amount of unwanted clothing that ends up in landfills. Global apparel production roughly doubled from 2000 to 2015, according to the Ellen MacArthur Foundation, which is committed to promoting sustainability. Over the same period, the number of times a piece of clothing was worn decreased by 36 percent. All in all, “the equivalent of a garbage truck full of clothes is being burned or dumped in a landfill every second,” the report said.

In roughly the same period, the World Economic Forum saw 60 percent more clothes bought, but consumers only kept them for half as long.

However, some companies like H&M are trying to improve their own sustainability while encouraging consumers to keep garments out of the trash. In the H & M flagship store in Stockholm, for example, customers can pay a nominal amount to have unwanted clothing converted into new clothing through a process that breaks down the old fibers and combines them with new ones.

The eight step process is meant to make a point, not a profit. “We want to involve our customers and make it clear to them that their own garments have value,” said Pascal Brun, Head of Sustainability at H & M.

However, traditional mechanical recycling, which is being used on a larger scale, has its limits. “As shiny as the fashion industry is, the supply chain has often relied on 19th-century equipment,” said Stacy Flynn, founder of Evrnu, a Seattle-based start-up. Companies like Ms. Flynn are trying to reduce fiber to its basic chemical components and rebuild it with less impact.

Evrnu’s first product, which Ms. Flynn hoped would be commercially available this year, converts the cotton used in clothing into lyocell, a cellulose fiber that is now made entirely from wood.

The process known as NuCycl updates the initial recycling step of sorting, sorting, and shredding fabric by adding a camera that can more accurately identify the composition of a fabric. Decorative embellishments, the content of the label or even the thread used can reduce the cotton content by up to 20 percent.

“It’s like the difference between cooking and baking – you can be more casual with ingredients in cooking, but you have to be precise when baking,” said Ms. Flynn. “It’s the same with chemical recycling. If you know what you have, you can optimize the process.”

In the next step, the heart of the technology lies in the pulp mill, where the shredded tissue is broken up and processed into pulp. This pulp becomes thick paper that is delivered to the next part of the textile supply chain, fiber manufacturers. There it is repolymerized to Lyocell.

Evrnu has partnered with several brands including Adidas and Ms. McCartney to use the recycled fibers in their fabrics. “When the consumer is done with it, or if the brand is stuck with a dog, these garments can all go back into the system, re-polymerized and turned into something new,” Ms. Flynn said.

Another area of ​​interest is new fibers and materials that are based on products that occur in nature but do not come from animals.

For example, some companies are developing alternatives to leather because hides are particularly problematic, from the methane-producing cows that produce it to tanning methods that often use toxic chemicals like chromium. Vegan leather, despite its eco-friendly name, is no better because it uses plastic, said Theanne Schiros, a materials scientist and assistant professor at the Fashion Institute of Technology in New York.

An alternative is mushroom leather, which relies on mycelium or fungal roots to make an animal-free alternative. Mycelium has been used in a variety of ways for thousands of years, said Dr. Schiros, even to treat wounds, but entrepreneurs and designers have set their goals higher.

In addition to Bolt Threads, a manufacturer of fibers and materials, which attracted attention last fall with the announcement of its product and the collaboration with several designers, other companies such as Mycoworks are developing “leather” from mycelium.

Mycowork managing director Matthew Scullin said while the company was researching its use in automotive upholstery, the current focus was on apparel and shoes.

Dr. FIT’s Schiros is part of a team at Columbia University working on an organic leather alternative. The latest prototype, she said, was “a naturally colored sneaker made from microbes that is part of Slow Factory’s One x One initiative,” and referred to the nonprofit that addresses sustainability and climate issues.

The pandemic has forced her to work from home rather than a lab, but she has come up with a clever solution.

She used her back yard to test how well the Bioleather treated with her herbal tanning technology would collapse – in which case, decomposition is a good thing. After burying the sample, she tested the mass of the material as well as the pH and nutrients of the soil for 60 days.

Her experiment at home found that after seven days the samples had visibly deteriorated, were smaller, and had lost over 70 percent of their mass.

Dr. Schiros is also the co-founder and Chief Science Officer of Werewool, which is developing an alternative to wool fibers. The company was founded by three of her former students at FIT and seeks to make biodegradable fibers based on the DNA of proteins that are already present in nature.

Dr. Schiros also worked on an algae-based yarn, which was also started at the school that is part of the State University of New York. The research is being carried out in collaboration with Columbia, where Dr. Schiros has an appointment as a research assistant.

Companies looking to offer “cradle-to-cradle” solutions – the term used for processes designed to keep materials in a circular economy, taking into account the final state of the materials at the beginning of the design process. That’s the idea behind Thousand Fell, a shoe manufacturer that primarily uses recycled materials, said the company’s co-founder, Chloe Songer.

Thousand Fell also wants to make it easier for consumers to recycle their shoes. “You can do great design thinking and great manufacturing, but if you’re not set up to actively collect products, it’s a little in vain,” said Stuart Ahlum, co-founder of the company. To that end, Thousand Fell partnered with UPS in November to provide consumers with an easier way to recycle their worn out shoes.

Ultimately, these developments will change the fashion world as long as customers keep shopping. The appearance and the price have to work. “If we could make a shoe for $ 400 but no one bought it, it would ruin its purpose,” said Ahlum.

In addition, being environmentally friendly is not enough. Dr. Scullin from Mycoworks said, “There is an expectation that consumers are willing to sacrifice quality for sustainability. But they are not. “