TOPSHAM — A 5 cent fee on single-use shopping bags and a ban on the use of polystyrene foam containers will take effect May 8.

Both ordinance changes were approved by referendum last November.

The ban on polystyrene foam containers blocks those typically used to serve or sell food. The retail sale of foam food or beverage containers will also be prohibited, according to an April 6 town news release.

“Existing businesses will be given a reasonable period of time to fully use existing stocks of polystyrene foam food and beverage containers on a case-by-case basis, based on unique situations,” the release said. “Items that arrive to the retail facility in a polystyrene container are exempt from these regulations, provided they were packaged outside of Topsham.”

Businesses such as grocery stores, convenience stores and restaurants, and town offices and departments, will be affected by the new rule.

The bag fee applies to stores that now offer customers single-use paper or plastic bags at no charge. Customers who want those bags will be charged 5 cents for each one. People who bring their own bags will not be charged.

The new rule will not apply to restaurants, but will affect stores whose food items make up more than 2 percent of their total sales.

Topsham will join Falmouth, Freeport, Kennebunk, Portland, South Portland and York in enacting the bag fee, according to baglaws.com. Decisions are pending in Brunswick and Windham.

The ordinances can be read at topshammaine.com. Those with questions can reach Codes Enforcement Officer Tom Lister at 725-1723, or Town Manager Rich Roedner at 725-5821.

A successful citizen petition drive by the Bring Your Own Bag Midcoast group, which has raised awareness of both issues in Topsham and Brunswick, put the bag fee and foam container bans on last year’s ballot.

Both products often end up as litter, the group has stated. Bags are recycled at a low rate in Maine, while foam containers are not recycled at all, according to the group, which has noted that there are alternatives at competitive costs.

The bag fee passed 3,062 to 2,876; the foam ban was approved 3,928 to 1,989. A six-month delay was allowed for implementation, Roedner said last week.

Virginia Moler of Bath unloads groceries purchased at the Hannaford supermarket in Topsham. A 5 cent fee for plastic shopping bags at grocery stores, and a ban on food containers made of polystyrene foam, take effect next month.