Coca Cola urged to cut out carcinogen

US watchdog the Centre for Science in the Public Interest (CSPI) says that Coca Cola from several countries, including Brazil, contains high levels of the carcinogen 4-methylimidazole. Its tests comes some months after the firm made changes to its drinks sold in California after a ballot initiative was passed in the state to limit people's exposure to carcinogens.

4-Methylimidazole is a byproduct of the industrial production of caramel, which is used as a colouring agent in colas. Mice fed a diet high in 4-methylimidazole have a higher risk of developing cancer. Caramel with reduced levels of 4-methylimidazole, however, is available and is already being used in Californian Coke.

After the decision to use this low 4-methylimidazole caramel to meet Californian regulations, Coca Cola also said that the replacement would be expanded to all suppliers, but CSPI tests show this has yet to happen. While a Californian bottle of the beverage was found to contain only 4µg of 4-methylimidizole, a similar sample from Brazil contained 267µg. However, the dietary intake linked with cancer in mice would equate to the average human consuming around 3g of 4-methylimidazole a day.