BEIJING, (Xinhuanet) -- "The caramel colouring used in Coca-Cola, Pepsi, and other foods is contaminated with two cancer-causing chemicals and should be banned," said the Center for Science in the Public Interest (CSPI). The center is a health lobby group based in Washington, DC, U.S., according to media reports.
Americas National Toxicology Program said that there is clear evidence that both 2-MI and 4-MI are animal carcinogens, and therefore likely to pose a risk to humans.
In U.S. government-conducted studies, two substances known as 2-MI and 4-MI caused lung, liver, or thyroid cancer or leukaemia in laboratory mice or rats.
Researchers at the University of California, Davis, found significant levels of 4-MI in five brands of cola.
Americas National Toxicology Program says that there is "clear evidence" that both 2-MI and 4-MI are animal carcinogens, and therefore likely to pose a risk to humans.
The executive director of the CSPI, Michael F Jacobson, has petitioned Americas food regulator, the Food & Drug Administration, to take action.
He said: "Carcinogenic colourings have no place in the food supply, especially considering that their only function is a cosmetic one."