A Kellog's worker urinated on a conveyor belt and is likely to have contaminated products which have since been eaten by consumers.
On 11 March, a video was published by the website World Star Hip Hop, appearing to show an employee of the cereal corporation urinating onto an active conveyor belt.
On Sunday, Kellogg's confirmed the video was shot in their Tennessee factory in 2014, though the mystery culprit remains at large.
A 2014 study found that 70 per cent of urine samples contained bacteria, with researchers documenting up to 33 different types of bacteria across the study.
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Urophagia, or the practice of consuming urine, was first promoted in the Damar Tantra, an ancident Hindu text. It was common in Ancient Egypt and China, and an estimated 3 million Chinese people still regularly drink their own urine.
However, this is not likely to be much consolation to anyone who purchased the affected products in 2014.
Rice Krispies Treats and other puffed rice products are believed to be the main items affected.
In a statement, a spokesperson wrote: "Kellogg's takes this situation very seriously and we were shocked and deeply disappointed by this video that we learned of. We immediately alerted law enforcement authorities and regulators.
"A criminal investigation is underway as well as a thorough internal investigation. Our investigation revealed that the video was recorded at our Memphis, [Tennessee] facility, in 2014.
"Products that could have been potentially affected were Rice Krispies Treats, Rice Krispies Treats cereal and puffed rice cake products, all of which would be past expiration date.
"Food quality is of the utmost importance to Kellogg Company. We are outraged by this completely unacceptable situation, and we will work closely with authorities to prosecute to the full extent of the law."
In 2012, a Taco Bell employee was fired for urinating onto a platter of Nachos, while in 2015 a Tesco's worker also lost his job after he was photographed relieving himself in a field of produce.Reuse content