Why you shouldn’t flush your contact lenses down the toilet or sink

About 125 million people use contact lenses worldwide. Not all of them are multi-use, in order that’s loads of contacts — probably billions — thrown away yearly.

Some folks flush their used every day contacts down the sink or toilet, however in line with new analysis, it is a horrible thought.

The research from Arizona State University, presented at the 256th National Meeting and Exposition of the American Chemical Society in Boston, discovered that discarding used lenses down the drain is contributing to plastic air pollution.

The lead writer Rolf Halden, the director of the Biodesign Institute’s Center for Environmental Health Engineering at ASU, stated he could not discover any research on what occurs to contact lenses after they’re used and discarded.

“I had worn glasses and contact lenses for most of my adult life,” Halden told ASU Now. “But I started to wonder, has anyone done research on what happens to these plastic lenses after their useful lifespan is over?”

Halden’s crew first carried out a survey of people that put on contact lenses, and examined 13 completely different manufacturers made out of 9 several types of plastic polymers.

“We found that 15 to 20% of contact-lens wearers are flushing the lenses down the sink or toilet,” stated Charles Rolsky, a PhD scholar who labored on the research.

“This is a pretty large number, considering roughly 45 million people in the U.S. alone wear contact lenses, amounting to 1.8-3.36 billion lenses flushed per year, or about 20-23 metric tons of wastewater-borne plastics annually.”

Contact lenses sometimes find yourself in wastewater-treatment vegetation, which fragment them into microplastics. In about two kilos of wastewater sludge, there tends to be one pair of contact lenses, the research discovered. So far, the damaging impacts of this are poorly understood, in line with Halden.

What is obvious is that it is regarding for contact lenses to make their manner into aquatic environments, as a result of sea creatures might mistake microplastics for food. Eventually, a few of it might make its manner up the food chain all the manner as much as people, as a result of we’re uncovered to plastics in seafood.

The crew additionally checked out how biodegradable contact lenses are by treating them with the anaerobic and cardio microorganisms present in wastewater-treatment vegetation.

“Whereas the lenses survived treatment for extended periods of time, we found noticeable changes in the bonds of the contact lenses as a result of exposure to microbes,” stated Varun Kelkar, one other writer of the research.

“When the lens plastic loses some of its structural strength, it will break down physically. This leads to smaller plastic particles, which ultimately will lead to the formation of microplastics.”

Microplastics are more and more turning into a burden on the atmosphere, with massive quantities of plastic particles making its manner round the oceans.

The researchers hope by highlighting this downside, contact lens producers will challenge security warnings on their containers for the most environmentally-friendly approach to eliminate lenses.

“A desirable long-term outcome would be to create lenses from polymers that are fine-tuned to be inert during use but labile and degradable when escaping into the environment,” stated Halden.