Thirty-seven pretzels that were "mistakenly contaminated with a granulated oven cleaner" were served to students at Fowler Middle School in Tigard, Ore., on Monday.Getty Images
Pretzels contaminated with an oven cleaner were served to dozens of students at an Oregon middle school this week.
Thirty-seven pretzels that were "mistakenly contaminated with a granulated oven cleaner" were served to students at Fowler Middle School on Monday, a spokesperson for the Tigard-Tualatin School District said.
As many as 50 students were affected and some reported discomfort in their mouth or throat, the district said.
The school district said it did not receive any reports of student hospitalizations.
When ingested, the oven cleaner -- Alto Shaam -- can bring on symptoms of a burning sensation, according to Oregon Health & Science University's Oregon Poison Center.
Ingestion of sodium hydroxide, an ingredient in the cleaner, can cause vomiting, abdominal pain and may lead to "perforation of the gastrointestinal tract and shock," according to the CDC.
The school district's director of communications said the incident was a result of "human error."
"We serve thousands of meals every day, and our first priority is always to protect the safety and well-being of our students," Alex Pulaski said. "In this instance, we erred, and we are working to rebuild trust as we conduct a full inquiry into what happened."
In a message sent to parents, Fowler Middle School Principal Cindy Pellicci said Oregon Poison Center was contacted immediately. She said all families whose children reported eating all or part of a pretzel were contacted by staff members.
"We understand that today's food incident created significant alarm within our school community," she wrote, adding that student safety is the district's "top priority" and "protocols were followed to immediately identify the students who ate the pretzels and check for illness or adverse reactions."
The school district said it is working to ensure families are reimbursed for any medical costs accumulated due to "this unfortunate incident."