A new study conducted by food testing company Clear Labs in US has discovered from a sample of 258 burgers, two cases of meat in vegetarian products, three burgers with rat DNA and one case of human DNA.

“The most likely cause is hair, skin, or fingernail that was accidentally mixed in during the manufacturing process,” the report mentioned referring to the human DNA.

“What many consumers don’t know is that some amounts of human and rat DNA may fall within an acceptable regulatory range,” the report added, as Independent mentions.

According to the study, there were “gaps” in food safety and quality standards, but overall the beef industry has “benefited from stringent regulation and aggressive testing requirements”.

Another problem found was that 4.3 per cent of burgers contained pathogenic DNA, which can cause tuberculosis-like symptoms, gastroenteritis, foodborne illness and E. coli.