A new study has revealed that 8 trillion plastic microbeads reach U.S. waterways every day, and the only way to prevent this is to ban the use of plastic microbeads, according to the researchers' recommendation, Discovery News reported.

Conservationists have long been lobbying for the ban of these tiny pieces of plastic, which are often used in various personal care products like exfoliants, body washes and toothpastes to achieve better scrubbing and cleaning. When such products are rinsed off, the plastic microbeads go down the drain with them.

Ranging in size from 5 µm to 1 mm, plastic microbeads are too small to be stopped by waste filtering systems. Eventually, they reach wastewater treatment plants, where some of them mix with effluent or liquid waste and get expelled into waterways. They travel to various rivers and lakes and then into the ocean.

"Part of this problem can now start with brushing your teeth in the morning," Stephanie Green, study co-author and research fellow at Oregon State University, said in a press release.

There are 0 to 7 pieces of plastic microbeads per L of effluent, according to estimates. That amount may not sound alarming, but in the U.S., 160 trillion L of effluent are treated daily.

To achieve a conservative estimate of how many plastic microbeads are released into bodies of water, the researchers made their calculations with the assumption that wastewater treatment plants process half the amount of sewage daily, with only 0.1 microbead per L of effluent.

The results showed that 8 trillion plastic microbeads make it to various bodies of water. If these are lined up side by side, they would cover an area of over 300 tennis courts. And that is just from the liquid waste. There are 800 trillion more plastic microbeads trapped in solid waste in the U.S. alone.

"Contaminants like these microbeads are not something our wastewater treatment plants were built to handle, and the overall amount of contamination is huge," Green said. "The microbeads are very durable."

Chelsea Rochman, lead study author and postdoctoral fellow at the University of California-Davis, said that these tiny pieces of plastic are a threat to wildlife.

"Microbeads are just one of many types of microplastic found in aquatic habitats and in the gut content of wildlife," Rochman said in the press release.

The researchers said that there is only one solution to the problem. Because present wastewater treatment plants are not able to handle the microplastics, banning the use of plastic microbeads is the best way to go. They were quick to note, however, that careful wording of legislation is necessary to make sure there are no loopholes to the ban.

"New wording should ensure that a material that is persistent, bioaccumulative, or toxic is not added to products designed to go down the drain," they wrote in the study.

The study was published in the Sept. 5 issue of the journal Environmental Science & Technology.