According to the Personal Care Products Council, "microbeads are plastic beads that are used as exfoliates in personal care cleansing products."

The organization states that microbeads have been used "because of their safe and effective exfoliating properties, and because they do not irritate the consumers' skin because of their low allergenic potential."

As such, microbeads are used in skincare products ranging from facial scrubs to industrial soaps for their scrubbing effect. One bottle of product can contain more than 300,000 microbeads.

Maryland House Bill 216 — which was signed into law earlier this year, and now limits the sale, manufacturing and production of microbeads in the state — defines a "synthetic plastic microbead" as any intentionally added solid plastic particle that is not biodegradable, less than 5 millimeters in size, and used in a rinse-off personal care product for exfoliation or cleansing purposes.

With such a proliferation of these microbeads in skincare products, a large amount are winding up down restroom drains and into The Great Lakes and other bodies of water.

According to the Alliance for the Great Lakes website, this poses a problem, "as the presence of microbeads in Great Lakes waters is a growing concern for fish and wildlife, and potentially for people living in the region."

"The concern is when you rinse that [product] ... into your sink, it ultimately ends up out in our waterways," says Jennifer Caddick, engagement director of The Alliance for the Great Lakes, Chicago. "Research about two years ago found really high concentrations of these little, tiny microplastics in the Great Lakes, which raises pretty significant concerns, considering the Great Lakes are the world's largest fresh water resource and a really important ecosystem for the region."

For Maryland Del. Dan Morhaim, the issue of microbeads in bodies of water also is what sparked him to sponsor legislation limiting them.

"In Maryland, we're very sensitive to the Chesapeake Bay," he says. "That's a big waterway for us, and we want to do our best to keep it clean and preserve it. But it's a global problem."

Research from the 5 Gyres Institute estimates that there are approximately 5.25 trillion pieces of plastic in the world's ocean; 92 percent of that is from microplastics, which includes microbeads.

Jonathan DePaolis is a freelance writer based in Frankfort, Illinois.