BUFFALO, N.Y. (AP) - Cosmetic products containing small plastic beads are now banned from being sold in upstate New York's most populous county.

Erie County Executive Mark Poloncarz on Thursday signed into law a local measure that bans the sale of personal cosmetic products containing microbeads. The signing comes after lawmakers in the county, which includes the city of Buffalo, approved the bill in a unanimous vote last month.

Supporters of the ban say the plastic particles are too fine to be caught in wastewater treatment plants and are flowing by the billions into the Great Lakes and other waterways. Scientists say they're also showing up inside fish that are caught for human consumption.

Stores will now have six months to pull microbead products down from their shelves or face possible fines.