If you're worried about the fish, you probably ditched your exfoliating face wash long ago. Microbeads, the little scrubby bits that did the exfoliating, are made of polyethylene plastic that doesn't degrade, meaning that when you flush it down the drain, trillions of those tiny beads end up in your local waterways. In 2015, Congress passed the Microbead-Free Waters Act, banning companies from manufacturing rinse-off cosmetics (like face washes) with them.
Unfortunately, as AlterNet informs us, face washes and other products covered by the law aren't the only problem. There are microplastics in glitter, too. Yes, your eyeshadow and trendy highlighter is killing the environment. And we all know how hard glitter is to get rid of.
Glitter is usually made by bonding some sort of reflective metal like aluminum foil to plastic. When you scrub those teeny pieces of plastic glitter off your skin in the shower, those microplastics end up in rivers, lakes, and oceans, where they pile up—and are eaten by fish and shellfish. (That said, a controversial 2016 study that said that fish prefer microplastics to natural food was retracted in 2017.)
The small fish eat the plastic, the big fish eat the small fish, and we, in turn, eat the big fish. A UN report in January 2017 found that microplastics make it back onto your plate, infiltrating the tissues of the fish you buy at the supermarket. And the plastic itself isn't even the whole problem—when plastic sits in the ocean, it's "a sponge for chemicals already out there," as marine ecologist Chelsea Rochman told NPR in 2013. The toxic chemicals in our waterways make it up the food chain on the backs of those glittery microplastics.
So yes, it's probably time to put away your highlighter and reconsider your New Year's décor. But, as with most environmental problems humans have wrought, that won't make the problem go away, since microplastics also come from [PDF] beach trash that degrades in the sunshine, from industrial sanding products, from tiny pieces of tires and fabrics, and more. But, as a baby step, go ahead and quit with the sparkly stuff.