So just how prevalent are microplastics in makeup? Allure did a random audit of more than 100 glittery and shimmery makeup products at a major beauty retailer, and found 32 percent contained microplastic glitters, which show up on ingredient lists as polyethylene terephthalate (PET). So…pretty prevalent. And how problematic are they? “The area of microplastics and its impact is still a pretty nascent field,” says chemist Sherri A. Mason, director of sustainability at Penn State Behrend in Erie, Pennsylvania. “But we know the chemicals within plastics may have a variety of human health impacts, from associations with certain types of cancer to issues with regard to reproduction, like sperm motility and pregnancy viability.”
There have been some efforts by a small but growing number of brands to move to the second type of cosmetic glitters: those made with cellulose (a plant-based or synthetic fiber). This seems like an exciting step forward, as Allure proclaimed in spring 2020, “When glitter is 100 percent biodegradable, we’re more than hopeful — we’re inspired.”
That was about a year before one of the first published studies looking at the environmental impact of different types of glitter, including “biodegradable” options. One cellulose iteration, which is technically modified regenerated cellulose (MRC), acted a lot like microplastic glitters in fresh water. Its presence was associated with a reduction in one plant’s root length by about a third, with chlorophyll levels down threefold, and a twofold increase in invasive mud snails that are typically found in polluted waters. “Glitter is like a Reese’s cup,” says Erdle. “The cellulose core provides shape and structure, but has to be wrapped in other materials that make it shiny and hold it together — and that is almost always aluminum and a plastic polymer film.”
But that study, which was published earlier this year, didn’t only look at PET and MRC, it also investigated natural and synthetic mica, the third ingredient that gives makeup shimmer and shine. (It’s also used in skin care because it creates the illusion of radiance.) “We found that each type of glitter, [PET, MRC, and mica], can negatively affect some aspect of microalgae and aquatic plants, which could have cascading effects on the food web,” says Dannielle Green, an associate professor of ecology at Anglia Ruskin University in Cambridge, England, who co-authored the study.
“I am finishing an experiment to answer the question [why].” But Green makes an important clarification: This pioneering study used very high concentrations of these particles, “reflecting a mass release of glitter” — think Coachella, the World Cup, a presidential inauguration. “We do not know if the effects persist at lower concentrations or in other settings,” she says. When it comes to mica, though, we do know there’s a huge social cost: One of the world’s largest exporters is Madagascar, where approximately 10,000 children, as young as four years old, work in mica mines, according to the United Nations Development Programme‘s MICA project. This is an industry that has been criticized for opaque supply chains and a lack of global regulation. India is also a large exporter of mica, and some recent reports even suggest that rates of child labor are up there, as families look for new sources of income after losing wages due to COVID. Unfortunately, there is no good way to tell if the mica you are buying has been responsibly sourced just by looking at a product, but certain brands have committed to using child-labor-free mica.