Used contact lenses go in the trash, not down the drain. That single habit change matters more than most people realize: roughly 1 in 5 contact lens wearers flush their lenses down the toilet or rinse them into the sink, sending an estimated 44,000 kilograms of plastic into US wastewater every year. Here’s how to handle every part of your lens waste, from the lenses themselves to the blister packs and solution bottles.
Why You Should Never Flush Contact Lenses
Contact lenses are made from hydrogel or silicone hydrogel plastics. When flushed or washed down a sink, they travel to wastewater treatment plants where bacteria are supposed to break down biological material. But lenses don’t cooperate. In lab tests simulating treatment plant conditions, lenses remained visually intact even after seven days of bacterial exposure. They eventually fragment into smaller pieces rather than truly decomposing.
Those fragments end up in sewage sludge, which is commonly spread on agricultural land as fertilizer. Researchers at Arizona State University estimated that about 24,000 kilograms of contact lens microplastics accumulate in US sewage sludge each year, destined for farm soil. From there, plastic particles can leach into groundwater and surface water, joining the broader microplastic pollution problem.
The Right Way to Throw Them Away
If recycling isn’t available near you, the simplest responsible option is putting used lenses in your household garbage. Remove the lens from your eye, place it in a small piece of tissue or directly into the trash. That’s it. Lenses that end up in a landfill aren’t ideal either, as they can take up to 500 years to decompose, but they’re far less harmful there than fragmenting in waterways and agricultural soil.
A few practical tips to make the habit stick:
- Keep a small container near your sink. A tiny jar or cup works as a collection spot so you’re not tempted to rinse lenses down the drain.
- Daily disposables add up fast. If you wear dailies in both eyes, that’s roughly 730 lenses a year. Collecting them before tossing makes the volume feel more tangible.
- Never put lenses in the recycling bin at home. They’re too small for standard recycling sorting equipment and will contaminate other recyclable materials.
Recycling Through the ONE by ONE Program
Bausch + Lomb runs the ONE by ONE recycling program in partnership with TerraCycle, and it’s currently the only dedicated contact lens recycling program in the US. It accepts used contact lenses, empty blister packs, and the foil lids from any brand, not just Bausch + Lomb products.
The program works through participating eye care practices. Each office receives a custom recycling bin from Bausch + Lomb. You bring in your used lenses and packaging, drop them in the bin, and the practice ships the collected materials to TerraCycle once the bin fills up. Shipping is free for the practice. To find a drop-off location near you, use the recycling center locator on TerraCycle’s website and search by zip code.
If you want to collect materials at home before making a trip, keep a small bag or container where you toss your used lenses and empty blister packs. Make sure everything is dry before you bag it up. When you have a reasonable amount, bring it all to your eye doctor’s office on your next visit or make a quick drop-off.
What to Do With Blister Packs and Foil Lids
Blister packs, the small plastic wells that hold individual lenses in saline, are not accepted by most curbside recycling programs. They’re made of mixed plastics that standard municipal sorting facilities can’t process efficiently. The foil lids peeled off the top have the same problem. Both components are accepted through the ONE by ONE program, so if you have access to a drop-off location, save them along with your used lenses.
If you don’t have a participating practice nearby, blister packs go in the regular trash. Drain out the saline solution first. The outer cardboard box that your lens supply comes in is standard cardboard and can go straight into your household recycling bin.
Disposing of Solution Bottles and Cases
Empty contact lens solution bottles are typically made of recyclable plastic. According to the American Optometric Association, these bottles can often go into your regular municipal recycling, though you should check your local guidelines since rules vary by city. Rinse the bottle, remove the cap (caps and bottles are often different plastic types), and check whether your local program accepts both.
Lens cases, the small plastic containers you store reusable lenses in overnight, are harder to recycle curbside because of their small size and mixed materials. These are best collected for a specialty recycling program or placed in the trash. If you wear two-week or monthly lenses, you should be replacing your case at least every three months anyway, so this is a recurring piece of waste worth thinking about.
Putting the Numbers in Perspective
About 45 million people in the US wear contact lenses. With one in five flushing their lenses, that’s roughly 9 million people regularly sending plastic down the drain. The total dry mass entering wastewater, 44,000 kilograms per year, might sound small compared to other plastic pollution sources, but contact lenses are particularly problematic because of where they end up. Unlike a plastic bottle floating in the ocean, lens fragments concentrate in sewage sludge that gets applied directly to farmland, creating a more targeted contamination pathway into soil and food systems.
Individual lenses are tiny, which makes it easy to assume they don’t matter. But millions of tiny plastic discs, each resistant to bacterial breakdown, add up to a real and measurable environmental load. The fix is straightforward: trash or recycle, never flush.