'MURICA — A new study by Arizona State University found that people discarding their disposable contacts by flushing them could be contributing to plastics pollution.
In the U.S., approximately 45 million people wear contacts. The study found around 15 to 20 percent of wearers don't dispose of their old lenses in waste containers, and instead flush them down toilets or sinks.
The study, presented at the National Meeting and Exposition of the American Chemical Society, estimates between 1.8 to 3.4 billion lenses get flushed per year, equaling 20 to 23 metric tons plastics waste.
Because the contact lenses are made with stronger plastics, they do not break down when exposed to microbes while going through a sewage treatment plant.
Researchers found that the old contacts instead become smaller pieces and are prevalent in wastewater sludge after sewage treatment.

The sludge is then deposited on land where lenses can then be washed into lakes and rivers where they are then by fish, birds or other animals.