It’s no surprise that 45 million people in the U.S. wear contact lenses – you’re probably one of them! But how you dispose of them may have a bigger environmental impact than you think.
According to a 2018 Arizona State University study, as many as 1 in 5 contact lens wearers dispose of their lenses down the sink or toilet, contributing an estimated 6-10 metric tons of plastic lenses to U.S. wastewater each year. Because of this, the lenses break down into microplastics at treatment plants, posing a risk to marine organisms and food supply.
Don’t they degrade?
It may be hard to believe that such tiny, flimsy pieces of plastic don’t just deteriorate over time, but they do not.
“They don’t degrade,” Rolf Halden, director of the Biodesign Institute at Arizona State University and one of the authors of the study, said. “They don’t attenuate, but they become smaller. So they create what we know as microplastic pollution, which is contaminating the oceans.”
Researches have an idea why contact lens wearers dispose of their contacts by flicking them down the toilet or sink – they don’t feel like solid waste. Because soft contacts are typically made from a combination of plastics, they feel watery and gel-like, which can make people think they are safe to flush down the toilet.
However, researches hope this study’s findings will convince people to stop flushing their contacts once they’re ready to be thrown away. They are also calling on lens manufacturers to, at the very least, label their products with proper disposal instructions.
“Ultimately, we hope that manufacturers will conduct more research on how the lenses impact aquatic life and how fast the lenses degrade in a marine environment,” Halden said.
Changing habits isn’t as hard as you may think
Angela Lashbrook, a reporter for The Atlantic, admitted she was guilty of disposing her contacts down the toilet.
“I hadn’t given much thought to throwing away my contacts in the toilet. I don’t do it often, just when the bathroom trash can is full. It doesn’t seem especially dangerous—contact lenses feel so impermanent, flimsy, and transparent that they’ll simply dissolve as they swirl down the drain.”
She wasn’t the only one.
“I asked a few of my contact-wearing friends, all in their 20s, about their disposal habits, and to my surprise, they all shared my flushing impulses,” Lashbrook said.
But after reading the study, she found that throwing her contacts in the trash vs. flushing them down the toilet wasn’t too much of an ask on her part.
“It’s quite possibly the easiest change to my behavior I’ve ever had to make that could avoid hurting the environment. My contact-wearing friends, without my scolding, all pledged to do the same,” Lashbrook wrote.