"They're rare but there's always a certain amount of risk involved, and I think you just have to go with that," said Keith-Thomas Ayoob, director of the nutrition clinic at the Albert Einstein College of Medicine in New York City. "Anytime there's human involvement, a factory is involved, once in a while there's going to be an [incident]."
But no such allowable levels for insect, rodent or other kind of contaminant exist for soft drinks, said FDA spokesman Michael Herndon.
Between Aug. 4 and Aug. 11, the FDA inspected the bottling plant in Orlando, Fla., where DeNegri's Pepsi came from and found no objectionable conditions and no evidence that might associate the plant with the problem, such as frogs or toads in the building.
Siobhan Delancy, a spokeswoman for the FDA, said investigators have not concluded how DeNegris' Diet Pepsi came to be contaminated.
The Pepsi Bottling Co. stood by its production facilities and said a breach in quality control was unlikely.
"There was nothing in the FDA test results that conclude that this was a manufacturing issue," said Jeff Dhanke, director of public relations for the Pepsi Bottling Group. "We have confidence that this is virtually impossible to have happened in a production environment. The well-being of our consumers -- there's nothing more important than that."
Amy DeNegri said she and her husband want an apology and some form of compensation from Pepsi, which they have not gotten and they are now seeking legal advice.