Federal health authorities have classified the recall of 13-ounce Lay’s Classic Potato Chips as a “Class 1” risk—the highest level—warning that consuming the product could result in severe allergic reactions or death due to undeclared milk.

The recall, affecting chips distributed in Washington and Oregon, was initiated after a customer alert, though no reactions have been reported.

Consumers are urged to check for bags with a “guaranteed fresh” date of February 11 and dispose of them immediately if they have a milk allergy.