With the stroke of the governor's pen on Monday, Maine became one of four states in the nation to ban single-use plastic bags.

The measure, signed by Gov. Janet Mills, takes effect on April 22, 2020. Fittingly, that is Earth Day.

The new law (LD 1532) will:

Prohibit the distribution of single-use plastic shopping bags at the point of sale at retail establishments in Maine; and

Place a minimum five-cent fee on recycled paper bags available at the point of sale at most retail locations, to provide an incentive for shoppers to use reusable bags.

The new law has exceptions for plastic bags used for certain uses including dry cleaning or loose produce.

Maine joined New York, California and, also on Monday, Vermont, as states to implement a statewide ban. Twenty-five Maine cities and towns already have banned or limited the use of plastic bags.

The measure is designed to reduce pollution while encouraging the use of reusable shopping bags.

Last month, Mills signed into law a ban on the use of styrofoam food containers.