We will try anything in the pursuit of beauty — from lead-laden face makeup and seaweed lipstick to whale mucus perfume. Though some of the remedies are benign, others can be patently poisonous. And in the case of modern hair dye, the chemicals can wreak havoc on the delicate locks we're trying to enhance.
Now scientists think they’ve got a solution. As Sheila Kaplan reports for The New York Times, researchers at Northwestern University have found that graphene, a carbon super material up to 300 times stronger than steel, makes a dark hair dye that’s supposedly safe, non-damaging and as permanent as other dyes on the market. They described their find in an article published in the journal Chem.
In an experiment, Jiaxing Huang, a materials scientist at Northwestern University and author of the study, used a graphene solution that included water, vitamin C and an adhesion polymer to coat platinum blond hair samples and wigs. The solution created a natural-looking black shade that’s often challenging to achieve with hair dyes. The color remained even after 30 washes — long enough to be considered permanent.
Hair dye kits on the market today often contain a mixture that includes ammonia or hydrogen peroxide to open the cuticle of the hair and deposit a more lasting color to each strand. Alternatively, bleach can be used to lighten natural hair coloring while peeling away the cuticle. But all of these compounds leave the hair brittle.
Some people are also concerned with the safety of traditional hair dye since the compounds can absorb into the skin. In the 1980s, several compounds in hair dye were found to cause cancer in animals. But these compounds are no longer in use and, according to the FDA, there is no "reliable evidence" to link cancer to hair dyes. But, as Kaplan notes, there are thousands of compounds in hair dyes today, and not all have been thoroughly tested for carcinogenic properties.
Unlike traditional dyes, however, graphene can’t penetrate the skin barrier. And it doesn't chemically alter the hair. “It doesn’t rely on any chemical reaction—you just brush it on the surface of the hair, comb it, and the hair changes color,” Huang tells Gizmodo’s Ed Cara.
But Andrew Maynard, director of Arizona State University’s Risk Innovation Lab who specializes in the environmental impacts of nanomaterials, isn’t so sure. As he writes for The Conversation, while engineered nanomaterials like graphene aren't necessarily harmful, there’s not enough research to suggest they’re totally safe either.
"[N]anomaterials can behave in unusual ways that depend on particle size, shape, chemistry and application," he writes. "Because of this, researchers have long been cautious about giving them a clean bill of health without first testing them extensively." There's no definitive answer for the safety of graphene, but Maynard points out that a growing body of evidence suggests the compound can cause lung damage in high concentrations could affect the biology of plants, algae and some invertebrates.
Isolated in 2004, graphene has grown in popularity, and these days is considered something of a super material with endless possibilities. Typically transparent, graphene turns brown when it comes in contact with oxygen or hydrogen, Cara reports. This oxidized version of graphene is what Huang used for his experiment, and the new dye could also become darker with UV radiation and other methods. While it can only turn hair into a color ranging from bronze to black for now, Huang tells Cara it could likely work for most color preferences. Cara also explains that while traditional dye typically creates frizz and flyaway hairs from static electricity, graphene doesn’t.
But graphene dye is far from hitting the shelves at your local drugstore. As Maynard writes, it will take much more research to ensure the safety of graphene hair dye.