The Food and Drug Administration has upgraded a December recall of Classic Lays Potato Chips to Class 1, the highest priority designated by the agency.

The FDA has upgraded a recall of Lay’s Potato Chips to the highest level possible, meaning consuming the chips will cause adverse health consequences. In December, Texas-based food manufacturer Frito Lay recalled a limited number of Lay’s Classic 13oz because the product could contain undeclared milk ingredients.

Broccoli packages sold at Walmart stores in 20 states have received an elevated recall status over a Listeria contamination that has potentially fatal consequences.