Maine has become the first state in the nation to ban Styrofoam containers.

Gov. Janet Mills signed into law last week a bill that would require companies to stop giving out cups and other single-use containers made of polystyrene foam, commonly known as Styrofoam, by January 2021.

Joining Boston Public Radio to weigh in was Corby Kummer, a senior editor at The Atlantic, an award-winning food writer, and a senior lecturer at the Tufts Friedman School of Nutrition and Policy.

Support for GBH is provided by:

Kummer explained that polystyrene products cannot be recycled in most statesand instead end up in landfills, where they don't biodegrade.

"In a million years, [the containers] don't degrade. Nothing happens to them. They just stay the way they are. This is why Styrofoam — or really polystyrene, [because] Styrofoam is a trade name, like Kleenex — doesn't degrade, it is the worst possible cause of plastics pollution," Kummer said.

Kummer praised the leadership of Mills, who began her term earlier this year, on this issue.

"This is such a sign that in the absence of federal leadership, it's locals who get things done," Kummer said.