Contact Lenses: A Hidden Plastic Waste Problem

Disposable contact lenses are, for many, a hugely convenient way of temporarily improving their vision without much upkeep. Pop them in, wear them, pop them out and bin or flush them.

Generally, that’s the lifecycle of the disposable contact lens. New research, however, says these small bits of plastic are actually adding up to one big plastic waste headache after we are done with them.

Researchers at Arizona State University had a vested interest in this research, namely because many of them are contact lens users who were also deeply interested in curbing plastic waste.

“I had worn glasses and contact lenses for most of my adult life,” says Rolf Halden, director of the Biodesign Institute’s Center for Environmental Health Engineering at ASU in a press release. “But I started to wonder, has anyone done research on what happens to these plastic lenses after their useful lifespan is over?”

It’s estimated that Americans alone use and throw away 14 billion lenses each year, so that’s no small amount. In fact, according to math whizzes over at the BBC this adds up to about 200,000 kg (441,000 lb) of discarded lenses every year.

So the researchers went to the source, the people who actually wear contact lenses, and asked them about how they disposed of their lenses. There were lots of answers, but one fact stood out. Around 15-20 percent of contact lens wearers said they either wash their lenses down the drain or that they flush them down the toilet.

This most likely means their lenses will end up in water treatment plants. We might think that’s no big deal and assume that the lenses will therefore be filtered out and dealt with appropriately. Unfortunately, that’s not possible.

What Happens When You Flush Your Contact Lenses?

The researchers believe that the way in which we treat waste water actually leads to contact lenses coming apart, turning them into microplastics. If this rings alarm bells, it should.

Microplastics are known to accumulate in our environments, particularly when they are consumed by microorganisms. When that happens, those microorganisms can fail to thrive or can pass on their tiny microplastics to larger animals who eat them, causing a knock-on effect up the food chain.

In terms of contact lens plastics, these microplastics will accumulate in sewage sludge. This material then goes to land management firms who use the sludge to treat and condition soil.

Not all the microplastics go to land treatment, though. This study wasn’t able to track microplastics entering water environments, but we know that runoff from soil can reach surface water and contaminate it. It’s also reasonable to expect that at least some of the microplastics from contact lenses are getting through the treatment process and making their way into wider aquatic environments.

What Can We Do About Contact Lens Waste?

To be clear here, this isn’t exactly the consumer’s fault. As a general rule, contact lenses aren’t recyclable. They are simply too small to be processed in traditional plastics recycling plants and therefore would require special techniques to be repurposed. As a result, people are just disposing of them however they think best.

Among the several brands surveyed for this research, the researchers could find only one brand, Bausch + Lomb ,that they say has set up a fully fleshed out recycling process, though it is worth noting that other manufacturers are going through the process and have some programs in place as interim steps.

This first-of-its kind research actually looked at the topic of contact lens microplastics in a great deal more detail, including how the polymers of the plastics break down in our water treatment plants, and for those interested I recommend the Arizona University overview of the study.

For our purposes as an action-oriented community, it’s enough to look at how we tackle this problem. The researchers have a number of suggestions.

“A simple first step would be for manufacturers to provide on product packaging, information on how to properly dispose of contact lenses, which is simply by placing them in the trash with other solid waste,” Halden says.

A more long-term action step would be for manufacturers to look at how they can create lenses that function perfectly well as lenses while in use, but that degrade when they reach our aquatic and land environments. That’s easy to say but possibly not easy to actually do.

Contact lenses are crucial for many people’s health and well being, but that shouldn’t come at the expense of the environment, if at all avoidable. This study highlights a problem that, until now, has been flying under the radar. It’s now up to contact lens manufacturers to step up and take action on better ways for us to manage our contact lens waste.

Photo credit: Thinkstock.


Marie W
Marie W3 months ago

Thanks for sharing

Gino C
Past Member 8 months ago

Thank you

Lisa M
Lisa M10 months ago


Lisa M
Lisa M10 months ago


Camilla V
Camilla Vaga10 months ago


Shirley S
Shirley S10 months ago


Alea C
Alea C10 months ago

I don't flush anything down the toilet except what belongs there. I'd like to only buy products that won't create microplastics, but that's impossible. Still, I do my best.

Teresa A
Teresa A10 months ago

Holly Windle and Wesley Struebing: you are right.

Loredana V
Loredana V10 months ago

I've never thought about it, I don't use contact lens. Thank you.

Holly Windle
Holly Windle10 months ago

Flush them down the drain?? Why? (I mean, yeah, if you drop one in the sink and it was about at the end of its wearability anyway.) But haven't these people ever had a clogged drain? Flicking one into the wastebasket is pretty easy.