July 2 (UPI) — After a voluntary recall of some Zapp’s and Dirty potato chips, the recall is now listed as the Food and Drug Administration’s highest risk category for salmonella poisoning.

The chips are made by Utz Quality Foods, which recalled the chips in May. The FDA has since classified the recall as a Class I recall.

A Class I recall is “a situation in which there is a reasonable probability that the use of or exposure to a violative product will cause serious adverse health consequences or death, the FDA’s website says.

The recalled products include:

• 1.5-ounce Zapp’s Brand Bayou Blackened Ranch Potato Chips
• 2.5-ounce Zapp’s Brand Bayou Blackened Ranch Potato Chips
• 8-ounce Zapp’s Brand Bayou Blackened Ranch Potato Chips
• 2-ounce Dirty Brand Salt and Vinegar Potato Chips
• 1.5-ounce Zapp’s Brand Salt and Vinegar Potato Chips (60 count)
• 2-ounce Dirty Brand Maui Onion Potato Chip
• 2.5-ounce Zapp’s Brand Big Cheezy Potato Chip
• 8-ounce Zapp’s Brand Big Cheezy Potato Chip
• 2-ounce Dirty Brand Sour Cream and Onion Potato Chips

Salmonella can cause serious, and even fatal infections in young children, elderly people, and people with weakened immune systems.

The recall was “out of an abundance of caution,” because the affected seasoning batches tested negative before use.

There have been no complaints of illness reported to Utz in connection with the recalled products. Utz is recalling these products based on the ingredient supplier’s recall.