HANOVER, Pa. (AP) — Pennsylvania-based chips and snack food maker Utz is recalling some of its tortilla chips because they may contain milk.

Utz Quality Foods announced the voluntarily recall Thursday of some of its Golden Flake, Good Health, Utz and Weis brand tortilla chip products. The items have been shipped to 31 states and the District of Columbia.

The company, based in Hanover, Pennsylvania, says the chips may contain milk not listed in the ingredients, which can lead to serious or life-threatening reactions to people with dairy allergies.

Anyone who purchased the chips can return them for a refund of exchange.