Utz has recalled certain Zapp’s and Dirty brand potato chips due to potential salmonella contamination. The recall was issued on May 4 for six types of Zapp’s and three types of Dirty chips.

The seasoning, made with dry milk powder, may contain salmonella. Affected batches tested negative for the bacteria, but Utz issued a voluntary recall as a precaution. As of May 4, no related illnesses have been reported.

The contamination also led to earlier recalls, including select Mama Cozzi’s breakfast pizza. The USDA expects more products to be affected as investigations continue.

Salmonella can cause salmonellosis, with symptoms including diarrhea, abdominal cramps, and fever. Symptoms typically appear six hours to six days after consumption and last four to seven days. Most recover without treatment, but older adults, infants, and those with weakened immune systems are at higher risk for severe illness.

Consumers should not eat the recalled chips and can contact Utz Customer Care at 1-877-423-0149 for refunds.