It only took 7-year-old Riley Chase one sip of his vanilla milkshake to realize that something was not right.
“Something was bubbling on my tongue,” he told ABC News of the milkshake he got from a drive-through Dairy Queen on Thursday.
Riley’s mother, Lisa Chase, tried the milkshake, too, and quickly felt that something was very wrong.
“It was just like you were drinking a very strong cleanser,” she said. “You could feel it go all the way into your stomach – it just burned all the way down.”
She immediately complained to the store, but, as she told 9 News, the employees were not helpful.
After they returned home, she called the store, at which point the manager admitted that there had been an alarming mix-up. A staff member had poured a chemical cleaner inside a bottle of vanilla syrup, and then left the syrup bottle in the sink.
The manager said that another employee picked up the bottle, thinking it was clean, and refilled it with vanilla syrup.
The container was found to have traces of a floor cleaner and de-greaser concentrate that contains sodium hydroxide, which can cause burns, vomiting and shock when ingested.
Both of the workers involved in the incident have been written up; the store owner has contacted poison control and the health department.
The Denver Post reports that Chase took Riley to the hospital on Friday as a precaution. She said that her son was feeling better after his hospital visit, but noted that the dangerous incident “could have cost people their lives.”
The franchise owner is now urging customers to come forward if they believe they consumed a contaminated vanilla milkshake.
ABC News reported that at least two other customers had ordered vanilla milkshakes and had to be treated at a hospital.