Plastic microbead scrubbers are history — at least in the United States.

President Obama has signed a bill that will outlaw use of the tiny spherical beads in beauty and personal care products. Companies that manufacture toothpaste and face and body washes that contain the scrubbers will begin phasing out the beads by mid-2017. The ban begins in earnest in 2018.

The polyethylene beads were commonly used as exfoliants and as abrasive agents in toothpastes, but never dissolve, which creates problems for wildlife. The beads are often so tiny that they can easily pass through wastewater treatment facilities untouched. They do not biodegrade, and can easily absorb toxic chemicals such as pesticides and flame retardants, which then end up in water, are eaten by phytoplankton and zooplankton, and in that way work their way up through the food chain.

Researchers began raising the alarm after testing bodies of fresh water such as the Great Lakes, and finding a remarkable amount of plastic microbead pollution, which they say can persist in the water and the food chain for centuries.

Further studies showed that micro plastics embedded themselves in the gastrointestinal tracts of fish, causing blockages and abrasions. There were also some reports of polyethylene balls getting lodged in the gums of people who used specific brands of whitening toothpastes.

Environmental activists applaud the ban, saying that there are plenty of biodegradable alternatives to plastic microbeads, such as sugar, sand, and ground cocoa beans.