In the second and third stages of the study the team looked at the form of plastics used in these lenses and found that they are made of soft plastics like poly (methylmethacrylate), silicones, and fluoropolymers. We are being warned not to throw contact lenses into toilets and sinks.
To understand how lenses break down in sewage, Rolsky and his colleagues placed the corrective lenses in wastewater treatment tanks filled with hungry microorganisms.
Wastewater treatment facilities in the US simply don't do a good enough job of filtering out the tons of contact lenses that are disposed of through the sewer system, according to new research presented Sunday at the American Chemical Society's meeting in Boston.
Researchers tracked them to waste water treatment plants, where they discovered the lenses fall apart but do not degrade. "This leads to smaller plastic particles which would ultimately lead to the formation of microplastics", Kelkar says. But according to a new research, they can contribute to microplastic pollution when not properly discarded.
The calculation of how many lenses end up in our wastewater plants and habitat hinged on a variety of data sources.
The full findings were discussed in the American Chemical Society 256th National Meeting.
Here & Now's Peter O'Dowd speaks with Rolf Halden, professor, director of the Center for Environmental Health Engineering at the Biodesign Institute and one of the authors of the new study. If you're tossing your disposable contacts in your toilet bowl, it might not be long before they come back to haunt you.
L'incroyable tweet du rappeur depuis sa cellule — Booba en prison
Toujours est-il que via son message: "Quand je serai grand, je voudrais être Benalla ou moine pédophile". Des individus comme Benalla ou un moine pédophile s'en tirent mieux que lui et Kaaris .
Halden assures contact lens users that they should not stop wearing lenses because of this study.
Charles Rolsky, a PhD student at ASU and one of the study authors, said: "We found that 15-20% of contact-lens wearers are flushing the lenses down the sink or toilet". Contacts are denser than water, which means they sink, and this could in due course pose a threat to marine life, particularly bottom feeders that may swallow the contacts, Halden says. The team collected parts of the lenses from the sludge and analyzed them. This leads to smaller plastic particles forming microplastics. Aquatic organisms can mistake these microplastics for food and since plastic is indigestible, this dramatically affects the marine animals' digestive system.
The plastic ends up entering the food chain through earthworms, it gets into rivers and oceans when it rains, or it gets directly to waterways when treatment plants experience overflows. This amounts to up to 3.36 billion lenses annually and around 50,000 pounds of plastic.
"We found that there were noticeable changes in the bonds of the contact lenses after long-term treatment with the plant's microbes", says coauthor Varun Kelkar.
A new study elaborated in the United States has concluded that contact lenses pose a serious threat for the aquatic creatures as they can be easily eaten by fish.
Even better he said would be for manufacturers to make it easier to recycle plastic contact lenses.
Contact lens companies often provide no package instructions about where to dispose of lenses, the ASU researchers note.