Maine became the first U.S. state to ban single-use foam containers this week, a major legislative victory meant to curb the flow of plastic pollution.

Gov. Janet Mills (D) signed a bill banning products made completely or partially of polystyrene on Tuesday. The products are often used just once before they’re thrown away, but they can survive in the environment for generations.

“While that cup of coffee may be finished, the Styrofoam cup it was in is not,” Mills said in a statement. “In fact, it will be around for decades to come and eventually it will break down into particles, polluting our environment, hurting our wildlife, and even detrimentally impacting our economy.”

The legislation will take effect on Jan. 1, 2021, providing businesses “ample time” to adapt, the governor said. Violators could face up to $100 in fines.

Some businesses will be exempt, including hospitals, seafood companies and state-funded Meals-on-Wheels programs, according to The Associated Press.

Environmental groups hailed the measure, saying it solidified the state’s reputation as a leader on green causes. Mills has taken a hard line on climate change as well, proposing a 27-member panel of experts this week to help the state dramatically reduce greenhouse gas emissions.

“Maine has proven itself as an environmental leader once again, this time in eliminating disposable foam containers that have become a common, costly, and deadly form of plastic pollution,” Sarah Lakeman, a sustainability director at the Natural Resources Council of Maine, said in a statement. “We need to be doing everything possible to limit our use and better manage our single-use plastics ― starting with eliminating the use of unnecessary foams like plastic foam.”