Toothpaste, body wash, and facial cleansers—if you use any of the hundreds of personal care products that contain microbeads, you’re contributing to the estimated 8 trillion tiny plastic spheres entering aquatic habitats in the United States every day. Need a little help wrapping your head around exactly what that amount of microbeads looks like? According to a new report released Friday from a group of scientists from seven colleges and universities, it’s enough to cover 300 tennis courts every day.

But it gets worse: The plastic particles are too small to be captured by wastewater treatment plants. In the report, published in the journal Environmental Science and Technology, the researchers estimated that 800 trillion of the abrasive beads may be in the sludge produced daily by sewage plants.

That sludge is sometimes used as fertilizer, which means once it rains—or once a farmer turns on an irrigation system—those beads may eventually end up in waterways too.

RELATED: 5 Shocking Photos of What It's Like to Swim in Ocean Plastic Pollution

“Contaminants like these microbeads are not something our wastewater treatment plants were built to handle, and the overall amount of contamination is huge. The microbeads are very durable,” Stephanie Green, a researcher at the College of Science at Oregon State University and coauthor of the report, said in a statement.

The only way to protect marine life—and ourselves, because really, who wants to eat plastic?—wrote the researchers, is an out-and-out international ban on microbeads.

“We’ve demonstrated in previous studies that microplastic of the same type, size, and shape as many microbeads can transfer contaminants to animals and cause toxic effects,” said Chelsea Rochman, a researcher at the University of California, Davis, and lead author of the report. “We argue that the scientific evidence regarding microplastic supports legislation calling for a removal of plastic microbeads from personal care products.”

Microbeads have been found in every ocean and in smaller bodies of water, including the Great Lakes and the Los Angeles River. But because they’re so tiny, when you’re at the beach, you don’t notice a microbead like you’d notice a plastic bottle cap or a candy wrapper floating along the shore. “We’re facing a plastic crisis and don’t even know it,” said Green.

A single container of face wash can have as many as 300,000 microbeads in it. And as much as companies tout their exfoliating properties, the miniscule plastic balls pack a serious polluting punch. A study released in August found that in the U.K. alone, as much as 80 tons of microbeads are being released into marine habitats every year.

RELATED: 8 Natural Exfoliants That Kick Polluting Microbeads to the Curb

In early September, California became the eighth state in the U.S. to pass a ban on microbeads—Colorado, Illinois, Maine, Wisconsin, New Jersey, Indiana, and Maryland are the others. Gov. Jerry Brown still has to sign the bill in the Golden State.

As this report points out, the language of some bans allows companies to slip through regulatory loopholes. Companies such as Johnson & Johnson and Procter & Gamble have pledged to stop using microbeads in their “rinse-off personal care products”—such as face wash. But because microbead-containing cosmetics, deodorants, lotions, nail polish, and cleaners don’t rinse off or aren’t always considered personal care products, companies may be able to get around the ban.

In many of these states, the prohibition on the microplastics won’t go into effect for several years. In California, popular brands that make microbead-containing products, such as Neutrogena and Aveeno, would be allowed to sell items containing microbeads until 2020.

Eight trillion beads a day times 1,825 days—go ahead, whip out your calculator and do the catastrophic math.