The United States and Canada throw out 32 tons of hair per day, according to a report from the waste management firm Green Circle Salons. But Kollar says there’s a better use for all those wasted locks: weaving them into clothing. In 2021, she launched a start-up, dubbed the Human Material Loop, to turn hair swept off the floors of salons and barbershops into fabric for clothes, curtains, carpets and furniture.
Kollar is part of a group of entrepreneurs and environmentalists looking for ways to recycle human hair. The wig industry has been putting long strands of cut hair to use for centuries. But more recently, companies and nonprofits have been turning shorter scraps of hair into fertilizer, using it to clean up oil spills or breaking it down into its essential amino acids for use in beauty products.
“We are moving into a world where sustainability is becoming an important concern,” said Marc André Meyers, a material scientist at the University of California at San Diego. “So we try to use materials from nature … and there’s a big push for natural fibers.”
Hair is so common that we often forget how remarkable it is. It has a strength-to-weight ratio similar to steel: One head of hair could suspend two elephants in the air. It holds heat, sheds water and traps oil. It springs back into shape when bent and can stretch up to 70 percent of its length without breaking — a trait that once allowed Greek and Roman soldiers to braid human hair into elastic ropes for catapults.
“Hair is more than just beauty,” Meyers said. “It has structure.”
That’s high praise from Meyers, who has dedicated much of his career to studying the structure of natural materials to find ways to put them to use or to draw inspiration for new products. Meyers has scrutinized tough but lightweight toucan beaks to come up with ideas for building airplane fuselages and studied the puncture-proof scales of the arapaima, an Amazonian fish that must fend off piranha bites, to suggest designs for body armor.
Meyers, along with colleagues at UC San Diego and the Swiss research university ETH Zurich, studied the structure of human hair in 2017. He says hair’s strength and its tendency to spring back into its original shape could help strengthen building materials in the same way steel rebar reinforces concrete walls.
But even Meyers, who saw airplanes in toucan beaks and body armor in fish scales, hadn’t considered weaving hair trimmings into a sweater. “The hair of sheep has been used for thousands of years as insulation in clothing. Now, can you use human hair? This is a complex technological problem,” he said. “I don’t have any answers.”
Kollar says she’s cracked the problem of turning locks of hair from the floors of salons into a fabric that looks and feels a lot like wool. “The length and color don’t matter,” she said. “We can use everything.”
The process involves treating the hair with chemicals, which clean it and change its color and texture so that it can be spun into yarn. Kollar says the chemicals are environmentally friendly and don’t pose a health hazard for humans or fish. The yarn can be dyed — any color but white, Kollar said — and woven into fabric like any other thread.
Although some fashion designers have made artsy garments that emphasize the fact that they come from human hair (see below), Kollar has tried to make her fabrics look as normal as possible. “Many times if people hear a fabric is made out of human hair, they’re like, ‘Eww!’” she said. “But if I just show them a sample and say, ‘What do you think of this?’ they’re like, ‘Oh, it’s cool.’ And then when I tell them afterward it’s made of hair, it’s a very different reaction.”
There are two environmental advantages of weaving with human hair, according to Kollar. First, it keeps hair out of landfills and incinerators, where it would release greenhouse gases while rotting or burning. Second, it avoids the consequences of clearing land to grow cotton, drilling oil to make synthetic fibers or shearing wool from sheep, which belch tons of planet-warming methane.
As an economic bonus, human hair comes free. Unlike sheep, people feed themselves, wash their own hair and pay to be shorn at barbershops and salons. All Kollar has to do is collect it.
But all the processing that comes afterward is expensive, especially because Human Material Loop is a start-up producing fabrics in small batches. Right now, Kollar says, her human hair fabric costs more than wool, cotton or polyester. “But once we reach a full-scale production, we can provide a very competitive price,” she said.
For the human-hair textile industry to take off, it would have to collect massive amounts of hair, which can be a logistical challenge. In India and Bangladesh, for example, the wig industry and fertilizer manufacturers rely on low-wage workers to sell their hair or collect it from salons.
“There’s a lot of human labor involved in collection,” said Ankush Gupta, who teaches chemistry at the Homi Bhabha Center for Science Education in Mumbai and wrote a 2014 paper on the uses of recycled hair. “Depending on the country, the cost of collection will go up … so perhaps it will be difficult to make it profitable.”
At first, Kollar experimented on her own hair, which she chopped into a short bob during early tests at a lab in Brightlands, a Dutch research hub, where she has been developing her textile technique with funding from the Dutch regional development agency LIOF.
But more recently, Kollar has gotten donations from hair salons, waste management companies and wig factories with leftover scraps of hair in the Netherlands, Belgium and Germany.
One model for large-scale hair collection is Matter of Trust, a nonprofit that runs one of the biggest hair collection operations in the United States. It brings in hundreds of tons of hair each year to create mats that clean up oil slicks or fertilize soil. Over the past 25 years, the group has recruited a network of thousands of donors — including barbershops, hair salons and regular people collecting their own hair trimmings — who drop off or mail in bags of hair.
“If you look in the garbage can of a hair salon, it’s 95 percent hair,” said Lisa Gautier, who founded Matter of Trust in 1998. “All we have to do is get that 5 percent of debris out of there. It’s really very doable.”
Up until now, Human Material Loop has worked with fashion designers to create prototype clothing that’s not for sale. In one experiment, Human Material Loop co-founder Leonardo Antonio Avezzano scaled Aconcagua, the tallest mountain in South America, wearing a jacket stuffed with human hair. But Kollar says that will change later this year, when a “high-end fashion brand,” which she didn’t name, will start selling a small number of made-to-order garments woven from her human hair fabrics.
If Kollar succeeds, she said, her goal is to produce about 550,000 tons of human hair fabric annually by 2034. That’s about a quarter of the size of the global wool market, and she said it would involve turning a quarter of all salon waste globally into fabric.
“Looking at fashion and how everything is disposable today in that space, we would like to develop something that can last decades and generations,” Kollar said. She points out that archaeologists have found mummies with human hair wigs that are thousands of years old.
“Imagine a sweater you can buy that will last 9,000 years,” she said. “The products we will produce will outlast humanity.”